Under Sea Adventurers Dive Club Social

Trouble at the Surface

Howard Ratsch — Fri, 20 Mar 2026 14:42:58 GMT

Trouble at the Surface

Ed.'s note: The incidents described here are real. Names of locations and people have been changed or deleted.

A middle-aged couple, Joe and Margaret Kirby, had recently been certified along with their teenage daughter, Becky. The family had made a few resort dives before signing up for their first really independent boat trip closer to home. The dive operator offered a dive guide for the day as the three were still novices, but they declined.

The day was beautiful with rolling waves, clear skies and a moderate breeze. Complete briefings were conducted at the dock and on arrival at the dive site. The dive area was popular, and several dive boats had already arrived and taken the available mooring buoys. The boat carrying Joe, Margaret and Becky anchored beside the reef in a sandy area. All of the dive boats there that day had student divers on board and planned their dives within the skill level of these divers.

After the student divers had entered the water, the Kirbys did likewise and made a free descent to the 40- to 60-foot depth range and, using a compass course, proceeded along the coral reef.

At about 70 feet, Becky indicated she had some difficulty, so they all surfaced together. At the surface, they discovered that they were quite far from their own boat and that they had traveled opposite from their intended direction but were near another boat that was on a mooring. They signaled back to their boat, giving the OK signal and what appeared to be a "come get me" signal. The skipper, seeing the conflicting signals, sent the divemaster out to investigate, while he continued to bring the students on board.

The divemaster swam out, made contact with the three divers and inflated all of their BCs, while evaluating the situation and making sure everyone was breathing OK. The divemaster provided reassurance while they waited for their boat to pick them up. Suddenly, Margaret, who was using her regulator to breathe on the surface, said she was out of air. A quick check of her pressure gauge showed 1,100 psi. She then dropped her regulator second stage from her mouth. The divemaster replaced it, and she dropped it again. At this point, he gave the emergency signal and started in-water mouth-to-mouth resuscitation.

The nearby dive boat dropped its mooring and was beside the divers in two to three minutes. Margaret was brought aboard and full CPR was administered during the rushed trip back to the dock, but to no avail.

In the legal action against the dive boat, skipper, divemaster and dive business, the family claimed that:

The conditions were unsafe, in particular that an extremely strong current of over three knots was running.
There was no dive briefing.
The divemaster did not swim out fast enough.
They should have used a chase boat, surfboard or float, pocket mask and an underwater recall.

NOAA had a continuously recording current meter on the reef at the site and depth of their dive, and, at the time of the accident, it recorded a variable current between zero and one-quarter of a knot.

Many student dives were made at the same time and place with no accidents or incidents. The procedures outlined in the briefings for divers who surface away from the boat indicated that divers should inflate their BCs, signal the boat and wait for pick-up. Of course, the boat would not put multiple students at risk by running the propellers while they were surfacing.

The divers did not follow the instructions to go down the anchor line and swim into the current; they incorrectly used their compass and went in the wrong direction.

When they first surfaced, Margaret was not having a problem. When she claimed she was out of air at 1,100 psi, it was a clear indication of stress, over breathing or circulatory distress.

The whole family was using private-label, mail-order BCs and regulators.

The autopsy gave drowning as cause of death, due to a heart attack brought on by morbid obesity, coronary atherosclerosis and other medical problems.

The court dismissed the case based on the waiver and release form signed by the victim.

For the rest of this article, use this link.

Trouble at the Surface | Scuba Diving

How to Control Seasickness

Howard Ratsch — Sun, 22 Feb 2026 12:58:21 GMT

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Copyright Disclaimer under section 107 of the Copyright Act of 1976, allowance is made for “fair use” for purposes such as criticism, comment, news reporting, teaching, scholarship, education and research. Fair use is a use permitted by copyright statute that might otherwise be infringing.

How to Control Seasickness

There are many ways to describe it: tossing your cookies, hugging the porcelain, calling for Ralph or letting out a technicolor yawn. but no matter what you call it, it’s no laughing matter. Motion sickness (seasickness, or “mal de mer”) is a common problem of boaters and divers. At best it is annoying, and at worst it becomes totally disabling. I will never forget crossing the ocean between Truk Lagoon and Pohnpei through very rough seas. As our boat scaled 10-foot/3-m swells and bounced off the backside of the rhythmic aquatic heights, my shipmates, a group of bronzed, sun-worshipping divers, went from golden-hued to green around the gills as soon as the seas picked up. Fortunately, I had placed a scopolamine patch (see below) behind my ear as soon as the surface began to get choppy. The drug worked well, and I was spared the wrath of an unsettled sea — and stomach.

What Causes Seasickness?

Seasickness is a complex phenomenon that involves the cerebellum (part of the brain that controls, among other things, balance), vestibular system (labyrinth of the inner ear that plays a major part in the control of equilibrium), the nerve connections between the eyes and the inner ear, and the gastrointestinal tract. It is made worse by alcohol ingestion, emotional upset, noxious odors (e.g., diesel exhaust fumes) and inner ear injury or infection. Motion sickness can be induced in a person who is not moving by having him watch an image of changing motion, such as a car chase or roller-coaster ride. Some of the special effects in current movies, particularly large-format ones like IMAX, can cause viewers to become dizzy or even mildly motion sick. Most persons adapt to real motion after a few days, but may require medication until they are adjusted to the environment.

Signs and symptoms of seasickness include a sensation of dizziness or spinning, a sensation of falling, pale skin color, sweating, nausea, weakness, yawning and increased salivation. Vomiting may provide temporary relief, but prolonged salvation does not occur until the inner ear labyrinth acclimatizes to motion or someone intervenes with medication.

How to Manage Motion Sickness

Here are a few tips to help you treat — or possibly prevent — a bout of seasickness:

Keep your eyes fixed on a steady point in the distance. If on board a ship, stay on deck. Splash your face with cold water. If the seas are rough, be careful not to slip or fall overboard.

Take meclizine (Antivert, Bonine) or cyclizine (Marezine) 25 mg orally, or dimenhydrinate (Dramamine) 50 mg orally, every six to 12 hours as necessary to prevent and control motion sickness. To be most effective, the first dose of medication should precede the environmental change by one hour. Medication given after the onset of seasickness will often be ineffective.
Obviously, if you are vomiting and cannot keep any medication down, you may need to use a suppository, such as prochlorperazine (Compazine) 25 mg or promethazine (Phenergen) 25 mg, noting that these drugs won’t cure the motion sickness. They might control vomiting, but have the side effect of drowsiness. Astemizole (Hismanal) is a nonsedating antihistamine that appears to suppress motion sickness as a side effect in some individuals. The dose is 10 mg by mouth every 24 hours. Persons with impaired liver function or who are taking ketoconazole, itraconazole, erythromycin, clarithromycin, or troleandomycin should not take this drug.
Place a transdermal scopolamine patch (Transderm-Scop) on the skin behind the ear. This patch releases the drug slowly through the skin and is effective against motion sickness for up to three days. Side effects include drowsiness, blurred vision (sometimes with a dilated pupil in the eye on the side of the patch), decreased sweating, difficulty with urination (particularly in elder males with enlarged prostate glands), dry mouth and a propensity to be susceptible to heat illness during times of heat exposure. On rare occasions, a person who uses a patch can become delirious as a side effect. Normal behavior returns within a few hours after the patch is removed.
Place a transdermal scopolamine patch (Transderm-Scop) on the skin behind the ear. This patch releases the drug slowly through the skin and is effective against motion sickness for up to three days. Side effects include drowsiness, blurred vision (sometimes with a dilated pupil in the eye on the side of the patch), decreased sweating, difficulty with urination (particularly in elder males with enlarged prostate glands), dry mouth and a propensity to be susceptible to heat illness during times of heat exposure. On rare occasions, a person who uses a patch can become delirious as a side effect. Normal behavior returns within a few hours after the patch is removed.
The patch should be positioned at least three hours before rough seas are encountered. If you touch the medicated (sticky) side of the patch with a finger and then let that finger come in contact with your eye, your pupil will almost certainly dilate and stay that way for up to eight hours.

For the remainder of this article use this link:

How To Control Seasickness - Dive Training Magazine | Scuba Diving Skills, Gear, Education

By Paul Auerbach, M.D.

What is visibility? Illuminating facts about an unclear situation

Howard Ratsch — Thu, 22 Jan 2026 11:48:28 GMT

This article represents the views of the authors. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

What is visibility? Illuminating facts about an unclear situation

By Robert N. Rossier

What’s the difference between a great dive and a mediocre dive? In most cases, it’s a matter of feet — not in terms of depth, but underwater visibility.

One of the most important considerations for diving is the “viz”. Clear water can make a mundane dive site shimmer in glory. Conversely, even the best coral reef can be a disappointment when it’s clouded by a veil of murky water.

Visibility is generally considered to be the distance at which an object underwater can be readily identified. Underwater visibility is measured two ways. There is horizontal visibility —how far you can see looking straight ahead — and vertical visibility — how far you can see looking up or down.

Horizontal visibility is usually more important, since it affects our ability to view the underwater environment and keep track of our dive buddies.

Despite its importance, visibility receives precious little attention in a basic scuba course.

That’s too bad because if you know something about the factors that affect visibility, you’ll

have a better chance of locating clearer waters.

Three factors primarily affect underwater visibility: light penetration, biological species and particulates. Not surprisingly, these factors are often related to one another, as well as to other environmental factors.

LIGHT PENETRATION

It only takes a couple of dives before we realize that sunlight plays a very important role in the visibility equation. Just as we can usually see better on the surface during a sunny day, the same generally holds true underwater.

The amount of light that will penetrate the water depends on three things: overall light levels (i.e., a cloudy versus a sunny day), the angle at which the light rays meet the water (called the “angle of incidence”) and the roughness of the surface.

While you may not be able to do anything about the clouds, you can plan your dives to take advantage of optimum light levels. In a geographic sense, when you’re near the equator,

where the sun’s rays are most intense, more light penetrates the water surface. In higher latitudes, the lower angle of incidence causes more light to be reflected, and less enters the water column. That’s one of the reasons why the water is almost always clearer in Bonaire (which is very close to the equator) than it is off the coast of New Jersey.

The location of the sun in the sky also affects light penetration, with the best light levels occurring around noon. The further the sun sinks on the horizon, the smaller its angle of incidence and the worse the visibility.

Sea state is another factor affecting light penetration. Rough seas reflect more light, thus reducing the underwater illumination. So if you’re choosing between two dive sites, opt for the one with calmer waters. The visibility will probably be better.

THE BIOLOGY OF VIZ

Use this link bwlow for the balance of this article.

What Is Visibility? Illuminating Facts About An Unclear Situation - Dive Training Magazine | Scuba Diving Skills, Gear, Education

Delays and Misdiagnosis

Howard Ratsch — Sun, 21 Dec 2025 21:34:24 GMT

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Delays and Misdiagnosis

By Jon Hardy

A physician named George took a tropical dive vacation with his wife Eve and teenage son Todd. The family took advantage of the two boat dives per day and unlimited shore diving offered by their resort. By Friday, George and his family were 13 dives into their weeklong vacation and planned only two morning boat dives so that they would have a 24-hour surface interval before their Saturday afternoon flight home.

When they surfaced at the stern of the dive boat after their second dive Friday morning, George and Todd let Eve board first. George started to tell Todd that he felt something was wrong when he suddenly lost consciousness.

Todd swam to his father immediately and yelled for help. The crew jumped into action and promptly got George and Todd out of the water and out of their dive gear. George regained consciousness quickly and, other than feeling out of sorts, he seemed to be all right.

While the crew secured the boat, George's symptoms worsened. Because English was not the boat crew's primary language, the family had difficulty communicating with them. No neurological exam was performed, no first aid was provided and George, the only person on hand with any medical training, was in no shape to provide a diagnosis. On the ride back to shore, the crew told the family that George must have been stung by something in the water and he would be better soon. They volunteered to arrange a ride to a local medical clinic.

When they arrived on shore, the dive guide called a cab, and George and his family went on their way. But the cab driver, seeing they were scuba divers, took them to the local hyperbaric chamber rather than the clinic. While paperwork was being completed and a medical exam was started for George, the dive guide from the boat caught up with them. The dive guide convinced George that he should go to the clinic, rather than be treated at the chamber.

After some delay, the clinic began administering oxygen, but stopped the oxygen treatment during the night when the oxygen supply was needed for another patient. The next day, with worsening symptoms, George was returned to the hyperbaric chamber and treated.

After multiple treatments at the local chamber and then back home, George was left with residual damage that precluded his continuing to perform surgery as part of his medical practice. He brought a legal action that was decided in his favor at trial.

George likely suffered from a poorly understood form of decompression illness that appears to be caused when a minor arterial gas embolism occurs in a diver who has significant nitrogen loading. This causes a hard-to-treat form of decompression sickness, Type III DCS.

Administering oxygen promptly to an injured diver is the best first aid, and getting hyperbaric oxygen therapy without needless delays is the definitive treatment.

If a diver suffers a lapse of consciousness upon surfacing, immediately suspect arterial gas embolism, administer first aid and get proper medical care.

Carry dive accident insurance so there is no question about payment for treatment.

Be assertive. Insist on medical care, and make it clear to the medical professionals that the injured person has been scuba diving.

Contact Divers Alert Network (919-684-4326) and enlist their help to find proper medical support or to consult with local physicians for you.

To the best of your ability, ensure that the dive boats you use have radios and oxygen, and that the crew is trained and prepared to use them. At least one crew member should be able to recognize and deal with the signs and symptoms of diving accidents. In countries where English is not the primary language, try to determine if the boat crews can function in English, even if things become difficult.

For the remainder of this article use the link below.

Delays and Misdiagnosis | Scuba Diving

How common is scuba diving PTSD?

Howard Ratsch — Fri, 21 Nov 2025 11:32:40 GMT

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of theUS Dive Club.

For the complete article, use the link below.

Scuba diving PTSD: how common is it, why does it matter and what may be done? – Fit To Dive

How common is scuba diving PTSD?2

Experiencing some lingering distress, mental or emotional issues after a traumatic experience is relatively common. Mostly, the person heals and the problem resolves naturally. However, for a proportion of people this reaction may develop into psychological stress injury or post-traumatic stress (disorder, i.e. PTSD). Divers do occasionally face challenging incidents or circumstances, such as decompression illness, barotrauma, entrapment/entanglement, lost gas events and rapid ascents. So it is reasonable to anticipate that some divers would be affected by psychological trauma issues.

This is likely partly due to the fact that these reports relate to the incident, any rescue and acute medical treatment. Data from longer-term follow up is harder to access. With psychological conditions, the impact of a traumatic event is not always apparent immediately. Also, during an incident and subsequent medical treatment, distress may be a normal response to what has happened. Diagnosis of PTSD would be much later, and so this data is not available for those reports.3

There is one study that specifically examined the psychological impact of accidents on recreational scuba divers. The research was carried out at the hyperbaric chamber in Orkney, which covers diving-related injuries in one of the world’s best known wreck diving locations: Scapa Flow. The study followed up all divers attending the chamber for diving-related conditions across two years. (Issues included: DCI, barotrauma, non-fatal drowning, marine stings, missed deco stops due to buoyancy or lack of gas supply). It measured reported symptoms of psychological trauma in: (a)victims of scuba diving accidents, (b) their buddies, and (c) another member of group who was not (or at least less) involved in the incident. All were measured at 3 months, 6 months and 12 months after the diving medical contact.

A few optional notes on quality of evidence

Before looking at the results of a study, it’s important to check the quality of the design and methods. This one has some good points. First of all, it’s prospective, that means it took a sample of people and followed them to see if there was an issue. (This is different from studying a group of people who are already reporting symptoms, for example). It could be said that to be truly prospective, it would start prior to the incident occurring at all. However, the authors considered this and included assessments of general mental health and a control group. In addition, they considered the statistical power of the study in advance and made sure to get enough participants to be confident that any difference in symptoms was not due to chance. The study also used a reliable and validated measure, one which is also clinically useful.

The study found that quite a substantial portion of the divers reported symptoms of psychological trauma, 3 months, 6 months and (in some cases) 12 months after the event. The victims reported significantly more symptoms than their buddy or the control. Divers were reporting symptoms of trauma on all three domains: avoidance, re-experiencing and arousal. So, we have an estimate that 25 to 50 % of divers are experiencing scuba diving PTSD symptoms after accidents. It is important to be clear that this does not mean that many divers get diagnosable PTSD. Instead, it is the number of the divers who reported some symptoms psychological trauma.

For

Fpr th4e

For the complete articl

The above are hih

Scuba diving PTSD

Waiting to Exhale: Diving’s Golden Rule Explained

Howard Ratsch — Thu, 30 Oct 2025 17:28:07 GMT

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

by Alex Brylske

As a child of the ’50s, I was a big fan of the hallmark TV series Sea Hunt and its indomitable hero, Mike Nelson, played by the late actor Lloyd Bridges. One episode I particularly remember involved the kidnapping of a scientist. As this was the era of Sputnik, it was implied — though never overtly stated — that the culprits were a group of “stinking commies.” The scientist was being held in a cave on an island. Central to the story line was the fact — seemingly unknown to the bad guys — that the cave could be entered from underwater.

Of course, Mike Nelson knew all about the underwater entryway and planned a highly sophisticated escape: he swam into the cave, distracted the guards, gave the scientist a 30-second scuba lesson, dodged a few bullets on the way out and — fade to black — the world was once again a safe place for mom, apple pie and clean-cut capitalists.

For years, I thought the episode was pretty bogus. Even as a kid I knew that becoming a scuba diver required hours of arduous training. I never gave the show much thought until years later when, following in my hero’s footsteps, I, too, became a scuba instructor. Even back then, everyone wanted to be like Mike. I soon came to realize that my hero hadn’t let me down after all. In fact, his 30-second lesson was brilliant in its cut-to-the-chase elegance, and certainly could have been enough training given the dire circumstance and high motivation of the unlucky victim. I don’t remember the dialogue verbatim, but it went something like this: “You see this thing? [pointing to the regulator mouthpiece] You put it in your mouth and breathe. Whatever you do, keep breathing; don’t ever hold your breath, or your lungs will burst and you’ll die!”

End of lesson. Any questions?

It was one of the few instances where Hollywood actually got the facts straight. If you had but 30 seconds to teach someone to scuba dive, what would you tell them? The same thing Mike did — the Golden Rule of scuba diving. Breathe normally; never hold your breath. The rest, in most cases, is pretty much secondary.

Of course, if you’re learning to dive without the distraction of gunfire, and your instructor has a bit more time to explain the nuances and importance of breathing, you probably will be subjected to either an illustration or an actual example of the most commonly used prop in diver training — the ubiquitous balloon. And the explanation, though lacking the dramatic effect that Lloyd Bridges could bring to the lesson, will be something like: If a flexible, gas-filled container — like a lung — can’t vent excess pressure as it rises in the water column, its volume will expand until it bursts. Of course, today you might have sophisticated video or computer-based graphics, but the essence of what Mike told the scientist remains the same.

Unfortunately, the balloon-aided explanation is about all that most divers ever learn. Now, there’s nothing really wrong with the balloon analogy. It’s just a bit oversimplified, especially if you really want to fully understand the consequences of forgetting what Mike Nelson so succinctly told the scientist. For one thing, our lungs bear little resemblance to balloons. (A sponge is a much more accurate analogy.) And due to the intricate and delicate nature of their anatomy, severe problems occur from lung expansion long before, as Mike so aptly put it, “your lungs burst and you die.”

For the remainder of this article, please use the linl below.

Waiting To Exhale: Diving’s Golden Rule Explained - Dive Training Magazine | Scuba Diving Skills, Gear, Education

Tips to Calculate Your Scuba Weight

Howard Ratsch — Mon, 22 Sep 2025 17:43:39 GMT

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Tips to Calculate Your Scuba Weight

You Have to Get Wet
It's no one item that determines your buoyancy, but you plus all your gear together.

You can "ballpark" guess how much weight you need with experience, but you can only fine tune it by getting in the water.

Pay Attention to Your Tank
Cylinder buoyancy characteristics change your buoyancy a lot. So, recheck your weight when changing to a different size and/or different material (steel vs aluminum) tank. Usually, but not always, going from aluminum to steel requires removing weight.

Air is Air
A common misconception is that with X cylinder, you don't need to worry about weight change due to air consumption. This is not true. Once you're properly weighted, consuming 70 cubic feet of air reduces your weight exactly the same whether it you breathed it from a steel or aluminum cylinder.

Build Muscle to Drop Weights
Muscle is denser than fat, so the more you build, the less weight you need to submerge.

Recheck
Any change to your kit affects your buoyancy. This is obvious with a big change ,like going from a wetsuit to a drysuit, but lots of little changes like a new knife, different computer and upgrading your regulator can add up

Check at Your Safety Stop
With 500 psi at 15 feet, if you vent all the air from your BCD, you should be very close to neutrally buoyant, rising slowly as you inhale, sink slowly as you exhale. If not, adjust your weight afterward -- but if you've followed the other steps, you should be very close and fine adjustments should do it.

Log It
Although you might find a scuba diving weight calculator or buoyancy calculator online, in the end they're only going to get you close and you'll still have to get wet to dial it in. A much more useful way is to write down what exposure suit you wore, what equipment you used, how much lead you carried, how much your body weighs, how much weight you needed etc., after each dive. This gives you a good start point for checking your weight each time, and over time you'll have the start point you want for different exposure suits, salt or fresh, aluminum or steel tank and so on.

Keep it up until you get your weighting correct. With experience, you'll discover that the best scuba weight calculator is your log book and brain followed by a buoyancy check. Even if you've got a new BCD or wetsuit, you'll be able to estimate the lead you need within a couple of pounds. You'll be your own dive weight calculator.

Breath Control
If your weighting is correct, at a given depth you can control your buoyancy with your lungs alone most of the time (unless you're using a rebreather). With practice, you'll do this without thinking instead of grabbing your low-pressure inflator hose every time you need to make a minor adjust

Be Patient.
Water is a viscous fluid, more like molasses than air, so buoyancy changes can seem slow or delayed if you're new to diving. When you want to ascend a little, you inhale and it takes a few beats before you start to rise. This is why many divers don't realize how well they can control their buoyancy with breathing. Give it a minute as you breathe in and out (slowly and deeply) to see what adjustment you can achieve naturally.

For the remainder of this article Use the link below.

Buoyancy Calculator—How Much You Need in Dive Weights | Scuba Diving

10 Ways To Save Your Life

Howard Ratsch — Thu, 21 Aug 2025 13:25:06 GMT

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

10 Ways To Save Your Life

By Jon Hardy |

The trial was heading into its third week. At stake was nearly $8 million and the future of diving. I was the last witness, called as a diving liability expert for the defense. Preliminary questions and direct examination established my qualifications, knowledge of the case and my opinion that the defendants — dive store, boat and dive leaders — were not at fault.

"So then, Mr. Hardy, in your expert opinion, who is negligent?"

"Mr. Paulis, the plaintiff."

"And how is he negligent for his own injuries?"

"Mr. Paulis is an experienced certified diver, and as such has certain responsibilities that only he can fulfill. He failed in several significant ways to meet those responsibilities.

"What are the specific responsibilities he failed to meet?"

"Mr. Paulis was not fit for this dive. His medical condition, his heart trouble that he concealed from the dive leaders, his lifestyle and recent illness all added to his physical and mental stress, which, when combined with the cold and fatigue he encountered on this dive, set him up for an accident. During the dive, he swam away not only from the group and the dive leader, but also from his buddy, so when he encountered difficulties, there was nobody there to help.

"Next, as the current increased, Mr. Paulis experienced difficulty swimming, breathing and controlling his buoyancy. Rather than pausing to regain control of the situation, he continued on until his level of stress was out of control, causing him to panic and begin an out-of-control ascent that led to an air embolism.

"The equipment, environment and the others on this dive were not the cause of Mr. Paulis's accident. He was. Fortunately, others were available when he surfaced unconscious, and they gave the best possible emergency care. Mr. Paulis is lucky to be alive."

And so it goes in case after case: Divers make mistakes, have accidents and then look for someone else to blame. Yes, there are cases where the dive leader, boat operator, store owner or manufacturer makes a mistake that harms the diver. That's why we have dive accident and liability insurance.

But the vast majority of diving accidents are caused by diver error. These accidents lead to legal actions and increased insurance costs for all. Most sadly, they lead to needless suffering and loss. After more than 25 years of investigating scuba accidents and testifying in trials all across the U.S., I've come to believe that most accidents can be prevented. How?

Below are 10 guidelines distilled from my involvement in hundreds of scuba accident investigations as well as from my experience as a dive instructor for nearly 40 years. Their purpose is to save lives. They are what I firmly believe instructors should emphasize in training courses.

Save Your Life: Have Good Overall Fitness

Rich swam over to his buddy, signaling frantically to share air. As the two share air, the buddy looks at Rich's pressure gauge. It still shows 1,500 psi. Suddenly Rich rejects his buddy's alternate air source and bolts for the surface, arriving unconscious and not breathing. Aggressive CPR brings him around, but he dies at the recompression chamber. An autopsy reveals a major heart attack, while the investigation uncovers a lifestyle that created a high risk of heart problems.

Several studies have indicated that 20 to 35 percent of all scuba fatalities result from heart and circulatory problems. Prior lifestyle and medical conditions set the stage, while the mental and physical stresses of diving trigger the event, usually in middle-aged men. Because the accident occurs in or under water, it is usually fatal and officially listed as a drowning.

Other fitness concerns include recent illness, the stresses of cold and fatigue, use of drugs and alcohol, and respiratory problems, including smoking. The keys to fitness are clear: eat well, exercise, get rest, and avoid stress and harmful habits. Easy to say, tough to do. What's easy, however, is for all divers, especially middle-aged men, to have a regular medical exam to determine whether they're fit for the stresses of diving. The small investment of time and money required for an annual physical is a big favor to yourself and everyone who cares about you — and could prevent as many as one-third of all scuba fatalities.

Save Your Life: Dive With Others & Know When and Where to Dive

While driving along the coast, Jan and Dave spot a beautiful cove. The surf's up, but it looks diveable to the experienced couple. They are alone as they climb down the cliff and prepare to dive. The swim out to the rock is easy, but then a large wave overwhelms them. When they bob back up to the surface Dave is unconscious and not breathing. Jan is trained in rescue, but it's too much for her. Alone in the water, she struggles to help Dave as he dies.

Diving solo or separated from other divers does not cause accidents, but it does mean that if something goes wrong, additional help is not available. Diving on organized trips, with dive clubs or dive stores, from dive boats or dive resorts, in dive classes or under other supervision ensures that dive professionals and emergency support equipment are available if a problem arises. Experience clearly demonstrates that when a dive leader is present, a potentially fatal accident often becomes a near-miss or a lesser injury. Diving with support and supervision is particularly important when you are new to diving or have been away from diving for a while.

Knowing when and where to dive takes skill and experience. One of diving's most important safety rules is that every diver has the right to make a "no dive" decision at any time before or during a dive, and that other divers will respect this decision regardless of whether it is based on environmental conditions, fitness, equipment or the planned dive activity. The bottom line: Know when to say no; know when to say enough.

For the remainder of this article use this link:

10 Ways To Save Your Life | Scuba Diving

Preparation for Foreign Dive Travel: Considerations for Local and Exotic Destinations

Howard Ratsch — Tue, 22 Jul 2025 14:06:07 GMT

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Preparation for Foreign Dive Travel: Considerations for Local and Exotic Destinations

Modern divers travel to all corners of the globe, and in doing so may encounter extraordinary health risks. These include uncommon bacterial and viral infections, tropical parasite infestations, marine animal envenomation, and exotic or contaminated food poisoning. According to Dr. Stuart Rose, who publishes the superb International Travel Health Guide each year (Travel Medicine, Inc., [800] 872-8633), factors which determine the risk of illness for a traveler overseas include the countries visited, the length of the trip, the use of prophylactic medications, personal protection against insect bites (DEET-containing insect repellent, permethrin-containing clothing spray or solution, mosquito netting around the bed), vaccinations received, health status, and personal behavior. In many foreign countries, sophisticated medical care is remote, or unavailable. Therefore, it is important for every traveling diver to anticipate likely health hazards and be prepared to act swiftly in the event of an illness or injury.

Preparation for foreign travel includes sufficient physical and dental examinations to identify treatable problems before undertaking the journey, obtaining appropriate immunizations, determining the need for any particular drug prophylaxis (e.g., against malaria), assembling a proper medical kit, and identifying medical resources along the route of travel and at the dive destination.

If you have not had a dental examination within the past six months, visit your dentist and complete any remedial dental work necessary to correct carious teeth, gum infection, eroding caps or crowns, and faulty dental appliances. Nothing ruins a trip faster than a toothache, and a dentist may be nowhere near the dive site. Have your doctor write prescriptions for all essential drugs you will be carrying so you may procure replacement drugs if your supply becomes exhausted or is lost. It doesn’t hurt to carry a letter from your physician as well, stating your medication list with doses. It’s also a good idea to carry a spare pair of glasses or contact lenses. Always take along a copy of your prescription in case you need to have new glasses made.

Medical emblems (e.g., bracelets) or wallet cards can prove extremely useful, particularly if you become incapacitated and cannot communicate your personal medical information with precision. Medic Alert, (800) 825-3785, is the best-known program, with body-worn emblems that are inscribed with a person’s most critical medical facts, as well as a telephone link to a 24-hour Emergency Response Center where more information can be obtained. The Life- Fax Emergency Medical Response System, (800) 962-8620, offers a wallet card which allows the card carrier to link to a central database and initiate an immediate fax of personal medical information to any location.

Be certain to identify the location of the nearest hyperbaric chamber facility, either by contacting the Divers Alert Network (DAN), (919) 684-2948, or the Undersea and Hyperbaric Medical Society, (301) 942-2980. The International Association for Medical Assistance to Travelers (IAMAT), (716) 754-4883, can provide you with a booklet listing English-speaking physicians and health clinics worldwide. In a crisis overseas for which you need translation, call the AT&T Language Line, (800) 628-8486.

Please use this link for the rest of the Diver Training Magazine article!

Preparation For Foreign Dive Travel: Considerations For Local And Exotic Destinations - Dive Training Magazine | Scuba Diving Skills, Gear, Education

The Deadly Risk of Neglecting Your Air

Howard Ratsch — Sun, 22 Jun 2025 15:38:47 GMT

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Copyright Disclaimer under section 107 of the Copyright Act of 1976, allowance is made for “fair use” for purposes such as criticism, comment, news reporting, teaching, scholarship, education and research. Fair use is a use permitted by copyright statute that might otherwise be infringing.

The Deadly Risk of Neglecting Your Air

A diver focuses on a new task rather than his air consumption

By Eric Douglas

Ben was new to spearfishing on scuba, but he was excited to try it. He just had to line up the perfect shot. The liveaboard’s chef told Ben if he got anything, he would cook it that night for dinner. Out of the corner of his eye, Ben saw his new dive buddy heading toward the surface. He remembered to check his air supply and realized he was nearly out of air.

THE DIVER

Ben was a 15-year-old male. He was certified as a PADI Junior Open Water Diver at age 13, but did not dive again for more than two years. When he received a trip on a local liveaboard dive boat as a gift, he knew he needed to prepare. He made 20 lake dives one month before attempting his first ocean dives on the liveaboard.

THE DIVE

On the first full day on the dive boat, Ben made six dives, including a night dive. The first dive on the second day was uneventful. Conditions were ideal, with more than 40 feet of visibility and only gentle currents. On the second dive that day, Ben took his new speargun with him. Ben was buddied up with another teen diver who had just completed his open water training and was making his first dive without an instructor.

THE INCIDENT

Ben’s buddy Lee realized he was down to about 1,000 psi in his tank and decided he needed to head back toward the boat. They were diving at a depth of around 90 feet. He tried to signal Ben, but Ben was too intent on stalking a fish to notice. Lee glanced back down to check on Ben as he ascended, and he saw Ben signaling that he needed to share air. Lee swam back down to help. They joined up, and Lee gave Ben his alternate air source. They began to ascend, but at about 70 feet, Ben took the backup regulator out of his mouth and grabbed Lee’s primary reg. After two breaths, Lee realized Ben wasn’t going to give his regulator back and jerked on the hose to retrieve it.

At that point, Ben simply fell away as if unconscious. Lee ran out of air on his ascent and surfaced rapidly. He ended up needing medical treatment and recompression in a hyperbaric chamber. Two other divers found Ben’s body at 94 feet and brought him to the surface. The boat crew performed CPR, but Ben did not come back.

ANALYSIS

The first lesson everyone can learn from this is just how quickly poor gas management can turn a perfect day into a disaster. Ben was nearly 100 feet down, but he wasn’t paying attention to the air in his tank. We don’t know exactly what happened, but he was likely focused on his first dive with a speargun and trying to bring back a fish. Underwater photographers can get themselves in trouble the same way—by focusing on the task rather than their diving skills.

The problem is task loading on a dive. For a relatively new diver, taking a speargun or a camera underwater can take their attention away from basic scuba skills like monitoring air supply, depth or their buddy’s location.

Ben refreshed his skills in the local lake after a two-year layoff following his certification, which was good, but he nonetheless allowed himself to get distracted. Ben was buddied up with another inexperienced diver and was using a speargun for the first time, which appears to have contributed. The two divers didn’t stay in contact, and Lee wasn’t confident enough to check in with Ben about his air supply or to notify his buddy when he decided to ascend.

It’s not uncommon for a stressed or panicked diver to feel as if they aren’t getting enough air from an alternate air source, even when it is working normally. The odd angle of the hose or even the orientation of the donated regulator can make breathing feel more difficult. Mistakes can happen in an emergency, especially when neither diver has practiced air-sharing techniques. At the end, Ben’s panic likely increased, which made him go for Lee’s regulator.

All of that could have been avoided if both divers had monitored each other and their air supplies like they had been taught.

LESSONS FOR LIFE

Monitor your gas: While a good buddy will check in with you, it’s ultimately your responsibility to monitor and plan your dive according to your gas.

Avoid task loading: Don’t introduce too many firsts on a dive. A new environment, new gear or a speargun or camera on a dive can be too many distractions, even for an experienced diver.

Practice air-sharing techniques: Practicing emergency drills in the water helps buddy teams become familiar with each other and keep skills fresh.

Link to the article:

The Deadly Risk of Neglecting Your Air | Scuba Diving

Trouble at the Surface

Howard Ratsch — Wed, 21 May 2025 11:32:31 GMT

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Trouble at the Surface

By Jon Hardy

Setting the Stage

Ed.'s note: The incidents described here are real. Names of locations and people have been changed or deleted.

The Dive and Rescue

After the student divers had entered the water, the Kirbys did likewise and made a free descent to the 40- to 60-foot depth range and, using a compass course, proceeded along the coral reef.

At about 70 feet, Becky indicated she had some difficulty, so they all surfaced together. At the surface, they discovered that they were quite far from their own boat and that they had traveled opposite from their intended direction, but were near another boat that was on a mooring. They signaled back to their boat, giving the OK signal and what appeared to be a "come get me" signal. The skipper, seeing the conflicting signals, sent the divemaster out to investigate, while he continued to bring the students on board.

Accusations, Analysis and Consequences

In the legal action against the dive boat, skipper, divemaster and dive business, the family claimed that:

The conditions were unsafe, in particular that an extremely strong current of over three knots was running.
There was no dive briefing.
The divemaster did not swim out fast enough.
They should have used a chase boat, surfboard or float, pocket mask and an underwater recall.

Subsequent investigation revealed that:

NOAA had a continuously recording current meter on the reef at the site and depth of their dive, and, at the time of the accident, it recorded a variable current between zero and one-quarter of a knot.
Many student dives were made at the same time and place with no accidents or incidents. The procedures outlined in the briefings for divers who surface away from the boat indicated that divers should inflate their BCs, signal the boat and wait for pick-up. Of course, the boat would not put multiple students at risk by running the propellers while they were surfacing.
The divers did not follow the instructions to go down the anchor line and swim into the current; they incorrectly used their compass and went in the wrong direction.
When they first surfaced, Margaret was not having a problem. When she claimed she was out of air at 1,100 psi, it was a clear indication of stress, over breathing or circulatory distress.
The whole family was using private-label, mail-order BCs and regulators.
The autopsy gave drowning as cause of death, due to a heart attack brought on by morbid obesity, coronary atherosclerosis and other medical problems.
The court dismissed the case based on the waiver and release form signed by the victim.

Lessons For Life

Be fit for diving, with particular emphasis on weight control in your middle years.
Follow the instructions of dive professionals.
Plan dives, and follow the plan, while allowing reasonable flexibility for unexpected opportunities or difficulties.
Know and use proper surface hand signals.
Buy quality dive gear.
Learn and use methods of underwater navigation, employing both natural aids and a compass.
If diving in a new environment or undertaking an unfamiliar dive activity, give serious consideration to the value of a professional guide.

Trouble at the Surface | Scuba Diving

Chest compressions — The first-line response

Howard Ratsch — Sun, 20 Apr 2025 15:40:09 GMT

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Copyright Disclaimer under section 107 of the Copyright Act of 1976, allowance is made for “fair use” for purposes such as criticism, comment, news reporting, teaching, scholarship, education and research. Fair use is a use permitted by copyright statute that might otherwise be infringing.

Chest compressions — The first-line response

Cardiopulmonary resuscitation (CPR) is a lifesaving skill, helpful in many situations including:

Cardiac arrest
Drowning
Trauma
Electrical shock

The American Heart Association recommends that everyone — untrained bystanders and medical personnel alike — begin CPR with chest compression. 1

CPR uses chest compression to imitate how the heart transports blood to the whole body. These compressions help keep oxygenated blood flowing to the brain and other vital organs until proper medical treatment can be provided. 2

During cardiac arrest, stoppage of oxygenated blood supply can damage the brain in only a few minutes. It can prove to be fatal within eight to ten minutes. 1

Why is compression necessary?

The opportunity for a successful resuscitation can be extended by keeping the blood flow active, even partially, until trained medical help arrives on site. 3

CPR saves a life

At present, about ninety percent of the people who suffer cardiac arrest outside the hospital expire. However, CPR improves the chances of saving a life if it is performed at the beginning of the cardiac arrest. The prospect of saving a person’s life can be double or triple with CPR. 2

Recognition of cardiac arrest

The person is healthy one moment, and you unexpectedly see or hear them fall down. You check for consciousness by “shaking and shouting” (Are you alright?) and rub the sternum with your knuckles. This helps to decide whether a person has had some other injury or they are suffering cardiac arrest. If the person doesn’t respond, you should assume that the person has experienced cardiac arrest.

Call for help immediately.

It is most important to call 911. Chest compression circulates some oxygen until help arrives. Tell someone or call yourself for emergency responders. Start chest compressions. Do not delay chest compressions if the pulse cannot be felt within 10 seconds. Immediate chest compression increases the chances of survival. 4

Chest compressions

A person present on the site, whether trained or not, should start chest compressions to the victim suffering cardiac arrest. Chest compressions are now the first-line response rather than opening the airway and delivering rescue breathing. High-quality chest compressions are necessary. Follow the mantra: “push fast and push hard on the center of the chest (i.e., sternum).”

Chest compressions must be at least 2 inches deep with each down-stroke.
The rate of compressions must be 100 to 120 per minute.
While performing chest compressions, the duration and frequency of interruptions must be minimized.

Chest compressions with ventilation can be provided by those trained in the technique and professional medical staff.

Complications

The object of chest compression is to supply blood to the brain, heart, and other vital organs of the body until accurate medical treatment can be provided. If chest compression is not started as quickly as possible, the person experiencing cardiac arrest is likely to die. Complications may include fractures of the ribs, broken teeth, infections, and punctures of the lung. 5 The risk of injury should not stop anyone from performing CPR. If CPR is performed on someone who doesn’t need it, though it can be uncomfortable for that person, only about 2% suffer any type of injury as a result.

Conclusion

It is very uncommon for only chest compressions to recover the heart. However, by continuing constant chest compressions you can dramatically improve the odds of survival by maintaining the victim’s heart in a condition that increases the likelihood that shocks from a defibrillator, administered through bystanders using an automated external defibrillator (AED) or administered by paramedics will result in survival. 4

Chest compressions are the first line response in CPR. If you are hesitant to do mouth-to-mouth, chest compressions alone may still be life-saving.5 It’s far better to do something than to do nothing if you are afraid and doubtful of your knowledge and abilities. Remember, the difference between you doing something and doing nothing could be someone’s life. 1 For more information in this regard check out our ACLS BLS recertification online and take CPR online classes.

Learn about BLS vs ACLS relation by checking out our online courses like online ACLS recertification and BLS certification and recertification courses.

References

https://www.mayoclinic.org/first-aid/first-aid-cpr/basics/art-20056600
https://www.cdc.gov/heart-disease/about/heart-attack.html
https://cpr.heart.org/en/resources/what-is-cpr
[https://heart.arizona.edu/heart-health/learn-cpr/frequently-asked-questions-about-chest-compression-only-cpr](https://heart.arizona.edu/heart-health/learn-cpr/frequently-asked-questions-about-chest-compression-only-cpr)
https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/cardiopulmonary-resuscitation-cpr

Reviewed by Jessica Munoz DPN, RN, CEN, providing nurse training at Yale New Haven Health-Bridgeport Hospital since 2022. Previously in healthcare and education at Griffin Hospital, St. Vincent's College of Nursing and Sacred Heart University Medical Center.

More by this author:

This page was last updated on Mar 3, 2025.

5 Tips To Stay Safe On Your Next Dive Trip

Howard Ratsch — Fri, 21 Mar 2025 12:34:43 GMT

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

5 Tips To Stay Safe On Your Next Dive Trip

Commit to these rules before you dive

By Brooke Morton Scuba Diving Magazine

1 Get Cleared To Dive If any aspect of your health has changed since your last dive trip, book a checkup. “Encourage your doctor to get on the phone with us” if they’re not familiar with dive safety, says Brian Harper, director of communications for Divers Alert Network. DAN has doctors who are experts in dive medicine and offers doctor consults daily. Another tip: “You’ll want to have been stable on any medications for a month prior to your trip.”

2 Bring Safety Gear If a destination is remote, has currents or allows divers to explore with a buddy and no guide, you’ll want to bring a personal locator beacon. At the very least, you’ll need a surface marker buoy—and the know-how to deploy it at depth. “That does a number of things: It allows the crew of your dive boat to keep tabs on your location and mitigates your risk of being lost or left behind, and it broadcasts your location to other boats, which reduces risks of propeller injuries,” says Harper.

3 Have Your Own Emergency Plan Every dive destination comes with a different set of risks. Research what those might be, and take the time to develop your own emergency action plan, or EAP. “Being an advocate for your own safety can pay dividends in terms of keeping yourself safe,” says Harper. On a liveaboard, for instance, plan how to get from your cabin to the emergency stations—and be able to do it blindfolded. “Chances are, in an emergency, you may not have lights.”

4 Take A Class If you don’t know the first thing about what to do in various emergencies, take a class. Some of the most relevant for divers include the DAN first-aid courses, Oxygen Administrator, CPR, Basic Life Support, and Hazardous Marine Life Injuries. “Becoming proficient in Basic Life Support is especially important if you’re traveling to remote locations and access to hospitals is delayed,” says Harper.

5 Invest In Peace Of Mind DAN membership and DAN Dive Accident Insurance are two separate purchases. DAN membership covers the transport to a treating facility, and accident insurance covers the cost of medical treatment. Without membership and dive accident insurance, each can cost tens of thousands of dollars.

Buoyancy Calculator—How Much You Need in Dive Weights

Howard Ratsch — Fri, 21 Feb 2025 16:28:40 GMT

This article represents the views of the authors. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Copyright Disclaimer under section 107 of the Copyright Act of 1976, allowance is made for “fair use” for purposes such as criticism, comment, news reporting, teaching, scholarship, education and research. Fair use is a use permitted by copyright statute that might otherwise be infringing.

Calculating the proper weight for diving lets you achieve neutral buoyancy

By Karl Shreeves |

Want to reduce your air consumption? Be able to fin faster and farther with less effort? Look relaxed and in perfect control? Finish the dive with less fatigue?

The secret is to pinpoint buoyancy control, and it all begins with fine-tuning your weighting—that's how much lead you thread on your belt or put into your integrated weight system. When you have exactly as much as you need, you have the smallest amount of air in your BCD needed for neutral buoyancy at a given depth. That means less drag and more efficient finning. It also means there's less BCD volume change with depth change, so you'll make smaller adjustments.

For the rest of this article, please use this link.

Buoyancy Calculator—How Much You Need in Dive Weights | Scuba Diving

Scuba Q & A: Common Questions Asked By Nondivers

Howard Ratsch — Tue, 21 Jan 2025 13:16:42 GMT

This article represents the views of the authors. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Scuba Q & A: Common Questions Asked By Nondivers

By Linda Lee Walden

When you tell friends and co-workers that you’ve recently been certified to scuba dive, their immediate reaction is likely to be an incredulous, “Wow. You did? I’m not sure I could do that!”

This knee-jerk response is often closely followed by a rash of questions indicating intense curiosity mixed with a touch of apprehension and perhaps a fair amount of misinformation. This article answers several of the questions most commonly asked by those who haven’t tried scuba yet. You can consider it a primer for the would-be diver, the friend, co-worker or family member who you think might enjoy our sport. By acting as a scuba steward, you might help turn a nondiver into a new diver — and maybe your dive buddy.

Is it hard to learn to scuba dive?

As active recreational pastimes go, scuba diving is one of the easiest to learn. While you’re gliding around enjoying the underwater sights, you’re engaged in only three basic skills: floating, kicking and breathing. Of course, there’s more to it that becoming proficient at using the equipment and developing knowledge of scuba concepts and safety procedures, but if you can breathe through your mouth, chances are you can learn to scuba dive.

The necessary skills are not tough for most people to master. During scuba certification class, you’re taught the effects of increased water pressure and safe diving practices. You rehearse equipment related skills in a controlled water setting until you feel comfortable, as well as practice what to do if things don’t go as planned.

The bulky scuba gear worn by many divers may seem intimidating, but learning to use it is straightforward. If you’ve snorkeled, you’re already familiar with the mask, snorkel and fins. The scuba unit consists of an air cylinder containing compressed breathing gas, buoyancy compensator (BC) jacket to help you float on the surface and maintain your desired depth underwater, and a regulator for you to breathe through. The exposure protection keeps you warm when diving in cool-water environments.

You don’t need to be a strong swimmer or an athlete to scuba dive, but some degree of comfort in the water certainly helps. Even if you enter scuba training with less than total confidence in your water skills, by the time you receive your first certification card, your comfort level will be greatly increased.

Learning to scuba dive is mostly a matter of attitude. If you are motivated to step through the door into an exciting new world, then the experience will prove both energizing and confidence-building.

For the balance of this article from Dive Training Magazine use this link.

Scuba Q & A: Common Questions Asked By Nondivers - Dive Training Magazine | Scuba Diving Skills, Gear, Education

8 Simple Ways You Can Help Improve Our Oceans’ Health

Howard Ratsch — Sat, 21 Dec 2024 13:37:37 GMT

This article represents the views of the authors. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

A Guide to Ocean Conservation Organizations and Efforts

The ocean is the largest ecosystem on Earth — it is the planet’s life support system and is affected by overfishing, pollution, and habitat...

The ocean is the largest ecosystem on Earth — it is the planet’s life support system and is affected by overfishing, pollution, and habitat destruction, compromising its ability to sustain humans with food, livelihoods and climate regulation. In this article, we’ll take a look at some of the movements and organizations making waves in ocean conservation

Healthy oceans sustain life here on planet earth — our security, our economy and our survival all require and are dependent on healthy oceans. Oceans provide us with food – seafood makes up at least a sixth of the animal protein people eat.

Oceans produce the air we breathe and the weather we experience. The ocean produces over half of the world’s oxygen and absorbs 50 times more carbon dioxide than our atmosphere.

Oceans regulate our climate. Covering 70 percent of the Earth’s surface, the ocean transports heat from the equator to the poles, regulating our climate and weather patterns.

From hotel rooms to dive trips and fishing trips, from clothing and fishing gear, the oceans support jobs. It is estimated that the oceans are responsible for more than $282B in revenue in the U.S. alone.

The ocean and its coral reefs provide natural breakwaters to buffer and protect our shorelines. The reef’s rough surfaces and complex structures dissipate the force of incoming waves, helping prevent flooding, erosion, property damage and loss of life.

Because of the impact the oceans have on every minute of every day, and on our future, ocean conservation is more essential now than ever before.

Many factors are affecting our oceans health today. Sea temperatures are increasing and the warmer oceans cause corals to bleach and die. Oceans today absorb about one-third of the carbon dioxide sent into the atmosphere — about 22 million tons a day. Increased carbon means higher levels of acidification — about 30 times greater than previous norms. This higher acidity results in the disruption of calcium carbonate formation. This can affect whole ecosystems, such as coral reefs, which depend on the formation of calcium carbonate to build reef structure, which in turn provides homes for reef organisms.

Pollution is a key factor in our oceans health. Many pesticides and nutrients used in agriculture end up in the coastal waters, resulting in oxygen depletion that kills marine plants and shellfish. Factories and industrial plants still discharge sewage and other runoff into the oceans. Oil spills pollute the oceans. Air pollution is responsible for almost one-third of the toxic contaminants and nutrients that enter coastal areas and oceans.

Over fishing is also contributing to our oceans declining health. The United Nations Food and Agriculture Organization estimates that 31.4 percent of fish stocks are either fished to capacity or over fished.

A recent Dive Training article, The Sickly Seas: Reaping the Unwanted Harvest of a Plastic Overload outlines the problem of plastic pollution in our oceans and how it’s endangering marine life including seabirds, and the fact that humans are indirectly consuming plastics through the seafood we eat.

Ocean Conservation: Turning the Tide

There’s no shortage of factors affecting the health of our oceans, but there’s good news on the horizon, too. Out there, beyond the predictions, are legions of individuals, communities, businesses, non-governmental agencies and governments working to solve the problems. Let’s take a look at some of the people helping to make ocean conservation a reality.

For the rest of this article use the link below/

A Guide To Ocean Conservation Organizations And Efforts - Dive Training Magazine

Did You See That? The Art of Observing Marine Life

Howard Ratsch — Fri, 22 Nov 2024 12:40:31 GMT

This article represents the views of the authors. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Copyright Disclaimer under section 107 of the Copyright Act of 1976, allowance is made for “fair use” for purposes such as criticism, comment, news reporting, teaching, scholarship, education and research. Fair use is a use permitted by copyright statute that might otherwise be infringing.

Did You See That? The Art of Observing Marine Life

By Marty Snyderman

The fish, a spectacularly colored grouper, paused and opened its mouth. Finning only slightly to maintain its position just a foot (30 cm) or so above the reef, this brightly colored red and blue-spotted grouper waited patiently for another fish, a cleaner wrasse, to provide its services. Within only a few seconds the cleaner approached and went to work, moving from the tail toward the head along the grouper’s body. The cleaner paused every few seconds to pick at the skin of the grouper.

Like other cleaner species, cleaner wrasses help rid groupers and other host animals of irritating ectoparasites that can be found on the skin of the hosts. In doing so the cleaners gain a meal while the host benefits by getting cleaned.

My dive buddy and I followed the grouper as it slowly moved down the reef. We watched as another fish, the same general size and shape as the cleaner wrasse, appeared. Looking quite confident that additional cleaning services were about to be rendered, the grouper paused and opened its mouth. In the blink of an eye, the fish I thought was a second cleaner wrasse swam up and bit a chunk of skin out of the side of the obviously startled grouper.

Clearly, the attacker was a mimic, a species that does a good enough job of imitating a cleaner species to fool groupers and other fishes into thinking the mimic is the real deal. It’s a risky business to try to fool well-equipped predators, but if well-done, the act of deceit can provide a mimic with a meal. If done badly, no more meals will be necessary. This mimic was a tiger blenny, a fact that, like the grouper, I realized only after the daring blenny had enjoyed its success.

After the dive I excitedly asked my diving buddy what she thought of the scene we had just witnessed, and much to my surprise, her only comment was, “that big fish sure is pretty.” At first I thought she was putting me on, but I soon realized that she had missed both the cleaning and the attack. She had noticed that the grouper had its mouth open rather wide, but she wasn’t sure why. She thought the fish might have been injured.

Observing marine life is like putting puzzle pieces together. When you look at one fish, you see only one piece of the puzzle. Yet when you connect the pieces — say a fish to its habitat and to other creatures within that habitat — you begin to see the inner workings of a marine ecosystem.

But how does one go from fish watcher to underwater naturalist? First, the more you dive, the more you will begin to see various subtleties, and the better observer you will become. You’ll find that your awareness of the underwater world increases with time, the number of dives and the variety of habitats you get to explore and enjoy. Second, it helps to learn about what’s going on under the waves so you are more likely to recognize the happenings that you encounter during your dives.

For the rest of this article, please use this link.

Did You See That? The Art Of Observing Marine Life - Dive Training Magazine | Scuba Diving Skills, Gear, Education

Take only pictures and leave bubbles!

Howard Ratsch — Fri, 25 Oct 2024 18:52:21 GMT

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Should artifacts be removed and recovered from shipwrecks, or should our underwater cultural heritage be left undisturbed? Regardless of what your choice is,, under which circumstances? These are the questions that Finnish CMAS instructor, and scientific diver Rupert Simon seeks to answer based on directives from UNESCO’s 2001 Convention along with several governments and training agencies.

Many years back, a fellow diver proudly showed me an amphorae (likely Roman) he had salvaged from a wreck in the Mediterranean Sea. Relatively recently, I watched a video in which a diver brings up an intact porthole from the bottom of the Baltic. Last December, I saw photos in a scuba blog that showed divers presenting their trophies—amongst them was a self-described “… avid collector of shipwreck artifacts.” These examples show that collecting artifacts from shipwrecks, which are de-facto archaeological sites of cultural heritage, is still common. I can’t help but wonder how the habit of collecting items from wrecks for personal benefit applies to the preservation goals taught throughout all main international scuba diving certification bodies.

For the complete Indepth article use the link below.

Take Only Pictures, Leave At Most Bubbles? The Case for Wreck Preservation - InDEPTH (indepthmag.com)

How Current Are Your Rescue Skills?

Howard Ratsch — Sun, 22 Sep 2024 13:49:59 GMT

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

DIVING SAFETY

How Current Are Your Rescue Skills?

By Wally Endres and Christine Tamburri.

When was the last time you had an in-water emergency while diving where your reaction saved a life? Maybe we should ask a more critical question: was it an event or was it actually an emergency? Are you a proactive or reactive diver?

For the full article in InDepth magazine, please use the link below.

How Current Are Your Rescue Skills? - InDEPTH (indepthmag.com)

Understanding Oxygen Toxicity: Part 1 – Looking Back

Howard Ratsch — Wed, 21 Aug 2024 14:26:40 GMT

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club

. Copyright Disclaimer under section 107 of the Copyright Act of 1976, allowance is made for “fair use” for purposes such as criticism, comment, news reporting, teaching, scholarship, education and research. Fair use is a use permitted by copyright statute that might otherwise be infringing.

Understanding Oxygen Toxicity: Part 1

Looking Back In this first of a two-part series, Diver Alert Network’s Reilly Fogarty examines the research that has led to our current working understanding of oxygen toxicity. He presents the history of oxygen toxicity research, our current toxicity models, the external risk factors we now understand, and what the future of this research will look like. Mind your PO2s!

For the entire InDEPT; article please use the link below.

Understanding Oxygen Toxicity: Part 1 – Looking Back - InDEPTH (indepthmag.com)

What to Do If You Have a Rash After Scuba Diving

Howard Ratsch — Sun, 21 Jul 2024 14:58:39 GMT

What to Do If You Have a Rash After Scuba Diving

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

An unexplained skin rash can mean more serious problems

By Eric Douglas

About an hour and a half after her second dive of the day, Jan’s buddy noticed a rash on Jan’s back and hip as she pulled her wetsuit down. They immediately alerted the dive crew.

The Diver

Jan was a 55-year-old diver who learned to dive for her 50th birthday. She made 15 to 20 dives each summer and was in overall good health.

The Dives

Jan and her buddy were on a daylong charter trip with three dives planned. They did two deep dives in the morning to explore an artificial reef. They planned for a shallower dive after a surface interval.

The Accident

After noticing the red and itchy rash on her back and side, Jan removed her wetsuit and took a warm shower. Cortisone cream relieved the itchiness, but her skin remained blotchy.

She called the emergency line at Divers Alert Network (DAN) after consulting with the crew, reporting no other signs or symptoms other than the rash. She had no dizziness, lethargy or loss of her ability to walk normally.

Jan skipped the third dive of the day and went to the emergency room once the boat returned to the dock.

Related Reading: The Risks of Forgoing Drysuit Training

Analysis

A sudden rash while diving could be sea lice or another ocean irritant, but the red-bluish discoloration underneath the skin indicated a likely case of skin bends.

Skin bends is a presentation of decompression sickness (DCS). It is a buildup of nitrogen in the tissues and bloodstream.

When a rash suddenly appears after a dive, especially a deep or long dive, it could signal a bigger issue and requires a full evaluation from a doctor trained in diving medicine. Look for areas of numbness or tingling in the body, extreme tiredness, feeling unsteady on your feet or even problems urinating.

Repeated instances of subcutaneous rashes or other more serious symptoms following diving may be a sign of a patent foramen ovale (PFO)—a hole in the heart wall between the upper chambers of the heart. Under the right conditions, it can allow blood from the venous circulation to pass into the arterial circulation. Nitrogen gas bubbles in the bloodstream would normally be filtered out by the lungs, but when they move into the arterial circulation, they can cause problems. Having a PFO is not a problem in everyday life, but it does increase the risk of more serious neurological DCS symptoms with diving. A surgical procedure can repair it.

Jan’s symptoms continued to resolve as she rested and hydrated. The emergency physician prescribed Benadryl, which seemed to help, but that doesn’t exclude the possibility of skin bends. With a potential DCS case, the boat crew should have administered oxygen.

Some divers make the mistake of diving even after symptoms appear. Jan wisely chose to skip the final dive. She returned to diving a week later but switched to nitrox and dived more conservatively.

Lessons For Life

Pay attention to your body. When unusual symptoms appear within 24 hours of diving, be aware that you may have a diving-related injury, and consult with DAN.
Understand the signs and symptoms. Learn what to watch for when it comes to decompression sickness.
Learn how to respond. Rescue and oxygen first-aid training prepare you to identify and respond to a suspected case of DCS in your dive buddy or yourself.

A “Handy” Way to Communicate: Using Hand Signals and Accessories to Communicate Underwater

Howard Ratsch — Sat, 22 Jun 2024 20:27:14 GMT

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

A “Handy” Way to Communicate: Using Hand Signals and Accessories to Communicate Underwater

COMMUNICATION IS THE act of exchanging information by signals or messages, including writing, talking and gesturing. The key word here is “exchange.” As we know, communicating clearly with someone is not always easy, even when the conversation is conducted using words spoken on dry land. For instance, if you are across a crowded, noisy room from the person you are trying to communicate with, they might not hear your message. Or if you’re speaking English to a non-English speaker, the message might not be understood even if the person is near enough for you to whisper in their ear. For solid communication to happen, your message must travel in a loop that sees it conveyed, received, understood, acknowledged and appropriately responded to. If the message gets hung up along the way, communication breaks down. This process becomes more complicated when we put a regulator in our mouth and jump into the water. For starters, having the regulator in our mouth makes talking difficult. Secondly, water makes sound waves go wonky, playing tricks on how we perceive sound underwater. This is why, as part of the Open Water Diver certification course, we all learn a variety of underwater hand signals commonly used in diving. In this article we’ll cover using hand signals and accessories for effective underwater communications.

Please use this DIVER MAGAZINE link below for the full article by Barry & Ruth Guimbellot

Underwater Hand Signals - Dive Training Magazine (dtmag.com)

Does The Sport Diving Community Learn from Accidents?

Howard Ratsch — Tue, 21 May 2024 17:53:21 GMT

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Does The Sport Diving Community Learn from Accidents?

by Gareth Lock

Do we learn from accidents as a diving culture and, as a result, take the actions, where needed, to improve divers’ safety? Though we might like to think that’s the case, the reality is more complicated as human factors coach Gareth Lock explains in some detail. Lock offers a broad six-point plan to help the community boost its learning chops. We gave him an A for effort. See what you think.

For the complete GUE article, please use the following link.

Does The Sport Diving Community Learn from Accidents? - InDepth (gue.com)

A Primer on Underwater Navigation Technology - InDepth (gue.com)

Howard Ratsch — Sun, 21 Apr 2024 18:07:31 GMT

A Primer on Underwater Navigation Technology - InDepth (gue.com)By Gabriel Pineda. Ocean Plan’s Navigator Pro.

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Underwater navigation seems like an obvious and useful extension of our dive computing capabilities. So why aren’t U/W NAV systems more prevalent? Former Shearwater director of sales and marketing Gabriel Pineda reviews the technology that exists today, discusses barriers to adoption, and offers some alternative approaches, including DIY solutions, to the problem of finding your way underwater.

For the entire GUE article please use the link below.

A Primer on Underwater Navigation Technology - InDepth (gue.com)

What to Do When You Overheat While Diving

Howard Ratsch — Fri, 22 Mar 2024 15:42:50 GMT

What to Do When You Overheat While Diving | Scuba Diving

An overheated diver catches a lucky break

By Eric Douglas

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

The air was hot, and all Diane could think about was getting in the water. Her drysuit made it even worse. She rushed to get to the swim step, telling her dive buddy she would meet him there. And then everything went dark.

The Diver

Diane was a 45-year-old diver in good physical condition, with PADI Advanced Open Water Diver and Dry Suit Diver certifications. She’d been diving for five years and had no known health conditions.

The Dive

Diane and her buddy were diving from a local charter boat with a planned depth of 80 feet. The air temperature was mid 80s, and there wasn’t much of a breeze. Surface water temperature was 64 degrees, but at depth it dropped to the 50s.

Diane was overheating as she sat in the sun waiting on her buddy. She’d already sealed the zipper on her drysuit so she decided to get in the water to cool off. She felt lightheaded when she stood up but made her way to the entry point and put on her fins. With Diane’s “OK,” the divemaster turned away to help other divers.

Related Reading: Ask DAN: How do I shore dive safely?

The Accident

Four other divers were already underwater when they saw Diane descending face-first like a rag doll. She was unconscious, and her regulator was out of her mouth. They saw her hit the bottom hard.

Three of them raced to help while the fourth headed to the surface to alert the boat crew. All the divers were PADI Rescue Diver certified. One attempted to get Diane’s regulator in her mouth, but when that failed, they inflated her BCD and escorted her to the surface.

The boat crew got Diane on board. She was not breathing, and her lips were blue. After a few minutes of CPR they noticed her breathing shallowly. They put her on oxygen first aid while heading to shore.

Diane was airlifted to a local medical facility and almost immediately recovered. She was later given a CT scan to determine the reason for losing consciousness. None was determined. She was released the next day with a perforated ear drum and soreness but was otherwise fine.

Analysis

Diane overheated and passed out as she stood on the swim step. Dive gear is often dark or black, making it uncomfortable to sit in under bright sun, especially when air temperatures are high. In situations like this, stay in the shade, stay hydrated and don your exposure protection at the last minute to avoid overheating.

The boat crew made a mistake by not observing Diane in the water or becoming concerned when she didn’t surface to wait for her dive buddy. But the most important takeaway from this accident is the quick reaction of the divers in the water and then by the boat crew on the surface. They performed CPR and administered oxygen. They also implemented their emergency plan and got an air evacuation on the way. The quick thinking and the actions of everyone involved saved Diane’s life.

Lessons For Life

Be prepared. Take a PADI Rescue Diver course and learn to respond in an emergency.

Avoid overheating. You can overheat quickly in dive gear. Don your exposure protection last-minute, or leave your suit unzipped to maintain a comfortable body temp.

Pay attention to your body. If you’re feeling lightheaded or otherwise unwell, take a minute to figure out what’s wrong. Collapsing on the boat in full gear can hurt. Losing consciousness in the water could be worse.

Delays and Misdiagnosis

Howard Ratsch — Fri, 23 Feb 2024 11:29:24 GMT

Delays and Misdiagnosis

By Jon Hardy

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Setting the Stage

The Accident

Analysis

Administering oxygen promptly to an injured diver is the best first aid, and getting hyperbaric oxygen therapy without needless delays is the definitive treatment.

Lessons for Life

If a diver suffers a lapse of consciousness upon surfacing, immediately suspect arterial gas embolism, administer first aid and get proper medical care.
Carry dive accident insurance so there is no question about payment for treatment.
Be assertive. Insist on medical care, and make it clear to the medical professionals that the injured person has been scuba diving.
Contact Divers Alert Network (919-684-4326) and enlist their help to find proper medical support or to consult with local physicians for you.
To the best of your ability, ensure that the dive boats you use have radios and oxygen, and that the crew is trained and prepared to use them. At least one crew member should be able to recognize and deal with the signs and symptoms of diving accidents. In countries where English is not the primary language, try to determine if the boat crews can function in English, even if things become difficult.

A Beginner's Guide to Wreck Diving

Howard Ratsch — Mon, 22 Jan 2024 17:40:21 GMT

A Beginner’s Guide to Wreck Diving

scuba.com

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Wreck diving is a specific type of scuba diving that requires added skill and provides a fulfilling experience for adventure seekers. Most wreck diving is done on shipwrecks, but it’s also common to explore sunken aircraft at the bottom of the sea floor. It’s become so popular among diving enthusiasts that retired ships have purposely been submerged to add to shipwrecks that can easily be accessed by beginners.

But don’t be fooled—wreck diving with actual shipwrecks from many years ago and at much greater depths can be perilous even for certified scuba divers. Below, we describe the allure of wreck diving, common wrecks that divers explore, the different types of wreck diving, safety accessories that you’ll need to bring, and the potential dangers you need to consider before you embark on your first underwater expedition.

For the complete article please use the following link.

A Beginner's Guide to Wreck Diving (scuba.com)

Sidemount By Stratis Kas

Howard Ratsch — Sun, 24 Dec 2023 11:21:59 GMT

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

If backmount diving is like space travel (equipment consistency, practicality, and universal acceptance as a gold standard without a legitimate reason), then sidemount must be like surfing (emphasis on individualism, competitiveness, self-proclaimed coolness and, of course, belonging to a “tribe” of few).

Now, everyone knows that I’m not very objective. I love sidemount to the point that if I cannot dive sidemount, I would often rather not dive at all. After years of pushing the limits with complex technical backmount dives, my first encounter with sidemount ignited a fire within me, reminiscent of that first exhilarating discovery dive. It was as if the underwater realm had unveiled a secret doorway, and all I had to do was step through with a permanent smile on my face, holding my regulator tight, knowing that a world of endless possibilities awaited.

But, in all seriousness, sidemount is just another diving configuration with (as any other) many pros and some cons. Even if sidemount was born out of logistical challenges related to equipment transportation in British dry caves, it has permeated nearly all diving situations today.

Nevertheless, sidemount is more complicated to get right than backmount, mostly due to the high personalization that is required to achieve its most important benchmark: a perfect trim. If you are new to sidemount, your journey may be a bit bumpy. But if you are already a devoted sidemount tribe member, you know that the journey truly never ends. Sidemount is organic—it keeps evolving.

For the complete GUE article, please use the following link.

The What, Which, and Why of Sidemount - InDepth (gue.com)

DCS What is Undeserved in “Undeserved Decompression Sickness”?

Howard Ratsch — Wed, 22 Nov 2023 15:25:53 GMT

DCS What is Undeserved in “Undeserved Decompression Sickness”?

by Neal W. Pollock, PhD

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Divers still seek comfort in the notion of the “underserved” hit to explain unexpected incidents of decompression sickness. “Hey, my computer said I was fine.” NOT. Here diving physiologist Dr. Neal Pollock exposes the fault in this notion. While decompression algorithms take into account the divers’ profiles, i.e., time and pressure, there are a multitude of factors that can potentially impact divers’ decompressions, as the author explains. Once divers’ reject the escapism that accompanies the ‘undeserved’ label, they can get on with the important business of diving and giving adequate consideration in their deco planning.

Spoiler Alert: the most undeserved element in the title is the word “undeserved.”

Describing cases of decompression sickness as “undeserved” generally speaks more from an emotional perspective than a rational one. The driving factors are typically faith in imperfect tools and a desire (conscious or unconscious) to shift responsibility.

Decompression algorithms rely almost exclusively on pressure and time data to predict effects. Enticing pictures can be painted on the authority of any algorithm, but the reality is that all rely on limited input to interpret complex situations for people who are not uniform. Modern decompression models are important constructs that can help us to dive safely, but the products are rudimentary from a physiological perspective, without sufficient sophistication to deserve unquestioned trust.

The dive profile is almost certainly the most important determinant of gas uptake and elimination, but the truth is that we do not yet have sufficient data to quantify the impact of many of the variables that can influence outcomes (Pollock 2016). Instead, algorithms rely on simple measures and mathematical bracketing with the hope of covering the contributing factors. The problem is not in doing this; the problem is in being surprised when the outcome is not what was expected.

For the remainder of this GUE In Depth article use the link below.

What is Undeserved in "Undeserved Decompression Sickness"? - InDepth (gue.com)

High-Pressure Hoses

Howard Ratsch — Mon, 23 Oct 2023 18:19:54 GMT

High-Pressure Hoses

by Francois Burman

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

A lurking peril

PEOPLE WHO HAVE FILLED scuba cylinders, refilled oxygen cylinders, or boosted a gas mix are familiar with using flexible hoses. Some hoses are covered with a durable rubber or thermoplastic jacket, while others appear even sturdier with a braided stainless-steel mesh on the outside. Correctly specified hoses are rated to pressures of up to 6,000 psi (414 bar).

When we first learn the basics of high pressures in hoses and cylinders, we are aware of the potential for serious injury to ourselves and those around us. If hoses fail, the results can be ear-shattering sounds, parts as projectiles, or an escaping gas stream that is strong enough to take out an eye. Without suitable restraints, hoses can whip around with sufficient force to amputate a limb.

Complacency often takes over in most cases, as hoses are sturdy and designed to be handled frequently and subjected to all kinds of abuses. But the risks never diminish, only our perception of risks.

The keys to hose safety are regular inspection, competent use, and replacement according to the manufacturer’s guidelines. Hose replacement is necessary with regular use and should occur more frequently with high usage or in humid areas where metals corrode easily.

The DAN Risk Assessment Guide for Dive Operators and Dive Professionals, which is available as a free download on DAN.org, contains a series of recommendations to address these risks. This information relates to selecting materials and manufacture, hose installation and use, and inspection and maintenance.

Please use the link below for the full DAN article.

High-Pressure Hoses - Divers Alert Network (dan.org)

Down Drafts: 5 Life-Saving Tips

Howard Ratsch — Fri, 22 Sep 2023 18:41:31 GMT

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Down Drafts: 5 Life-Saving Tips

By Jon Hardy

Case 1

Ed.'s note: The incidents described here are real. Names of locations and people have been changed or deleted.

The diving had been great — five days of easy drift diving on a Caribbean island known for its walls. Although Anne dived only on vacation once a year, she had her own gear and had been doing these dive trips for many years. She had never taken any advanced training or a scuba refresher, but she was comfortable diving. It was so easy to just drift and let the dive guides and boat crews deal with all the logistics, planning and details of the diving.

Anne preferred the smaller boats with fewer divers, signing up for her dives directly with local dive operators after she arrived on island. For her last day of diving, she wanted to do something special, so she shopped around for an operator going to a dive site she hadn't been to. A small local operation was offering a trip to a remote reef known for its unique marine life and strong current.

The trip out to the site was easy, although this boat was not as fast or as large as the others she had been on. It also did not carry oxygen or have a radio. The crew and dive guide spoke only limited English, but were friendly and helpful. Anne entered the water with the small group of divers and the guide after a limited briefing.

She was never seen again.

As it turned out, the edge of this reef had a significant downwelling. As the large mass of water, driven by the strong current, reached the edge of the reef, it plunged downward into the abyss.

The dive boat returned to shore without Anne. Not knowing where she was staying, the operator decided to wait until someone asked about her, and therefore made no report that she was missing. Because Anne was single and lived alone, it wasn't until the next week, when she did not return to work, that her family started an investigation, which led from the airline to the hotel to the dive operator.

The family's desire to bring a legal action against the dive operator turned out to be hopeless. The legal system of the country in which the accident happened allowed for little litigation, the few legal actions that were permitted had extremely low monetary limits, and the ability of American attorneys to function in the foreign court was extremely limited.

Case 2

One evening after dinner, a dive instructor's phone rang.

"Hello, this is Fred," the instructor answered.

Fred, this is Neal. You saved my life, man!"

"Oh, really? How so?"

Neal had taken a weeklong dive trip on a live-aboard in the Pacific. On many of the dives, a small tender from the live-aboard took divers to a site, dropped them off, then picked then up as they surfaced. On one trip, the divers were dropped off near an island with the admonition to stay close to shore. The offshore currents were not only strong, but vortexes were not uncommon in this area, causing the water to swirl in a downward flow, as in a whirlpool.

Due to delays among the other divers, and the crew not being sure of their position, Neal was the last to enter the water. By the time he descended, he was not only no longer with the group, he was also not with his assigned buddy. He almost immediately realized that he was in a very strong current with no bottom in sight. Putting it all together — no group, no buddy, no bottom, strong current — Neal decided to abort the dive and started swimming for the surface. Within moments, he realized that not only was he not moving toward the surface, he was being pulled downward at an accelerating rate.

Fear was rapidly turning to panic as he passed 100 feet, still kicking. Then the voice of his instructor, Fred, started playing inside his head — "If all hope is lost, get positively buoyant." Neal ditched his weights, pushed his power inflator button and continued to kick for the surface. After a few more agonizing moments, he paused at 135 feet, then started up, at first slowly, then faster and faster until he had to dump air from his BC to slow his ascent as he approached the surface.

The crew later apologized for their mistake of dropping divers at the wrong place. Neal suffered no physical injury from his near-miss, but he became much more careful about putting his safety in the hands of others.

Lessons For Life

Be aware of what dive guides and boat crews are doing.
Do not give the responsibility for your safety to others.
Be sure that any boat you dive from has a radio and carries oxygen.
Let someone else know your plans and be sure the dive operator takes emergency contact information.
If you're unable to deal with a problem under water, get positively buoyant and go to the surface. If possible, slow down or stop on the way up, but remember that it's far better to risk decompression illness and be on the surface breathing, than to be on the bottom not breathing.

A Buddy's Best Effort Fails

Howard Ratsch — Mon, 21 Aug 2023 13:18:38 GMT

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

A Buddy's Best Effort Fails

By Jon Hardy

Setting the Stage

Ed.'s note: The incidents described here are real. Names of locations and people have been changed or deleted.

Joe and Mac went through the same open-water certification course and buddied for all of their post-certification dives. Shortly after, the dive store that offered their diving course and supplied their rental equipment sponsored a boat diving trip, with their instructor serving as divemaster and coordinator.

On the first day of the trip, Joe and Mac dived with their instructor Fred on two wrecks in the 70- to 90-foot range. Both dived in a safe and conscientious manner. For the next dive day, Joe and Mac asked Fred to let them dive on their own, which he willingly agreed to.

The next morning, Mac appeared to be congested and to have an upset stomach; he may have taken some non-prescription medication. The boat ride out to the dive site was smooth, the water clear and calm. Joe and Mac made their own plan to dive the wreck. Fred approved the plan and they were on their way with no sign of stress or difficulty.

The Dive

Joe and Mac descended with ease. At the base of the mooring, around 80 feet, they adjusted their buoyancy and swam the wreck, side by side. After a very short time, Mac stopped suddenly. Joe swam close to check Mac's condition. Mac reached for Joe's octopus, was handed it by Joe, and took two or three deep breaths. Joe then took hold of Mac and started swimming to the mooring line. As he did, the octopus fell from Mac's mouth and Joe replaced it. This happened twice. Joe now realized that Mac was in serious trouble, added air to his own BC and ascended, while holding onto Mac. They ascended quickly, but under control, not pausing for a safety stop. At the surface, Joe raised his hand and yelled. Immediately divers from one of the other dive boats helped pull Mac on board, began giving CPR, and then raced to shore. An ambulance transferred Mac to a hospital where he was pronounced dead from a combination of air embolism and drowning.

Legal Action and Analysis

Mac's family sued the dive store and the instructor. Their claims against the store and instructor included renting defective equipment, providing improper training, keeping poor records, diving beyond 60 feet and failing to provide direct supervision.

During the discovery process and subsequent trial, some of the realities of recreational diving were clarified:

Dive equipment rarely causes diving accidents, and, in this case, no defect could be found that related to the actual events.
Although Fred was an instructor, he was not teaching at the time of the dives; his original training of these divers had been more than adequate; the divers had successfully made several dives without an instructor after their certification.
How well dive rosters and log books are completed does not cause diving accidents.
The dive industry's recommendations on such things as depth limits are just that — suggestions, not regulations.
Indirect supervision is the most common method used by dive professionals when supervising certified divers. Given this, there is nothing a dive professional can do to directly aid a diver in need.
Dive professionals do not have police powers to keep certified divers from diving. In fact, in this case, Joe and Mac were not only certified, but their experience exceeded the dives done in an Advanced Open Water course.
Joe's rescue efforts to help Mac were exactly what a dive professional would have done in the same situation.

We will never know what actually happened to Mac, but it was clear some medical condition caused him respiratory distress and did not allow his airway to equalize on the way to the surface. There is nothing a rescuer can do to open another diver's airway while under water. If a diver is not breathing, the best course of action is to get to the surface with all deliberate speed. The dive store was dropped from the case, and the jury found in favor of the defendant instructor.

Lessons for Life

Be fit for diving — free from illness and not medicated to cover up an underlying illness.
If you should ever throw up under water, do so through your regulator and then clear it or switch to your octopus for a clear airway.

PADI highlights 5 safety points in response to fatalities

Howard Ratsch — Sat, 22 Jul 2023 13:54:00 GMT

PADI Highlights 5 Safety Points in Response to Fatalities

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Following several fatal incidents involving PADI professionals, the diver training organisation has issued a statement warning dive-centers and instructors of any agency against losing sight of safety standards and practices.

“Diver safety is each and every diving professional’s first and most important priority, because when it’s lacking, preventable tragedies can occur,” says PADI Worldwide CEO and president Drew Richardson. “Dive incidents ripple well beyond the victims. They are deep, personal tragedies also impacting families, friends and the entire global diving community – regardless of the diving organisation individuals are associated with.

“There is generally a reasonably low risk in diving when community, training-course and safe diving practices are followed but, when they are not, the severity of a potential accident will have serious consequences that could have been entirely avoidable,” says Richardson.

“While most diving professionals put safety first, recent incidents where fatalities have occurred were not simple slips or forgetful moments. These tragedies resulted directly or indirectly from violating course standards, abandoning sound judgment and ignoring or over-riding obvious and accepted dive-community practices.”

For the remaining part of this article, please use the Divernet.com link below.

PADI highlights 5 safety points in response to fatalities (divernet.com)

Deploying a Safety Sausage

Howard Ratsch — Fri, 16 Jun 2023 17:36:20 GMT

Deploying a Safety Sausage

By Barry & Ruth Guimbellot

Deploying A Safety Sausage - Scuba Skills | Dive Training Magazine (dtmag.com)

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

ONE ESSENTIAL PIECE of accessory equipment every diver needs to carry is the “safety sausage” or surface marker buoy (SMB). This device may also be referred to as a DSMB (delayed or deployable surface marker buoy). The purpose of these buoys is to help you be located quickly and easily during and/or after a dive. Knowing how to deploy an inflatable buoy is important, so let’s get started.

Safety Sausage Basics

An SMB or safety sausage can be any type of buoyant object used to indicate a diver’s position — a ring buoy, a large round float or a diver down flag mounted on a float and pole, for instance. For the purposes of this article, the SMB we’re describing is a portable, inflatable tube ranging from 3 to 6 feet (1 to 2 m) feet in length. SMBs come in bright colors, enabling boat crews and fellow divers to locate your position. Common colors are orange, red, pink and yellow. In some locations, yellow is reserved for emergencies. If you intend to use a yellow buoy, let your boat crew and dive buddies know so they will not mistake it as an emergency signal. The SMB may or may not have an attached line and spool/reel.

A DSMB must have an attached line and spool or reel to be used to mark a diver’s location underwater. In some instances, divers deploy and tow a DSMB throughout the dive. In other instances, the DSMB is deployed near the end of the dive, usually as the divers prepare to ascend to safety stop depth.

A typical SMB consists of an inflatable tube outfitted with a valve used to inflate the tube by mouth or a valve that accepts a low-pressure inflator hose. Larger SMBs have dump valves to deflate the tube after use or to allow air to escape to avoid over-pressurization as the tube rises to the surface.

BYOB. In this instance BYOB means, “Bring Your Own Buoy.” Every diver should equip with his or her own personal SMB when diving in the ocean or other large body of water — especially when diving from a boat. In the event that buddy teams become separated, each diver can inflate their own buoy and get seen — and reunited — sooner.

An open-cell safety sausage tube opens at the bottom so it can be inflated with a second-stage regulator. With this type of tube, the opening must remain below the surface to avoid air from escaping, thus deflating the tube. When inflating this type of tube, be careful not to entangle the regulator in the opening.

Most SMBs have reflective material on the tube, which is useful at night when using searchlights. For additional safety, some reflectors are visible to radar. Tubes also have a D-ring or similar connector to attach a line and spool/reel to the tube. The SMB typically has a strap to keep the tube rolled up when not in use. Some tubes also have a D-ring located on top to attach a strobe light or light stick. Some models come with an accessory pocket.

When selecting a buoy, ask the pros at your local dive center for assistance. They can help you select the right buoy, line and spool/reel and other accessories such as clips and straps that will be suitable for the type of diving you intend to do.

Using a Buoy

Again, the main purpose of the SMB is to make you (or your position underwater) more visible to those on the surface. When live boating — diving from a boat that does not anchor — the SMB is especially useful if deployed while you are performing your safety stop or preparing to begin your ascent. By the time you surface, the boat can be nearby ready to assist you back onboard.

When night diving from shore or a boat, shining a light up through the bottom of the SMB tube provides a glow that is easily seen by fellow divers. If the tube does not open on the end, hold your dive light near the side to light up the tube.

The line attached to your DSMB can also be a handy reference for your safety stop. For example, tie knots in the line at about 15 and 20 feet below the bottom of the tube. When rewinding the line as you ascend, the knots in the line will indicate you are at safety stop depth. The reference mark is especially useful when in limited visibility or diving at night. (Always use your dive computer and/or depth gauge for accuracy.)

The DSMB can also be used underwater to mark a spot on the reef, providing divers with a needed reference point. If diving from shore, the DSMB can designate the starting point to return to at the end of the dive. In either case, the tube will be partially inflated and the line unrolled a few feet/meters. The line and spool/reel will need to be anchored using a lead weight or tied off to a rock or other fixed, nonliving underwater feature.

Tips for Deploying a Surface Marker Buoy

You may find it easier to retrieve the SMB tube from your buoyancy compensator (BC) pocket or D-ring when at safety stop depth or deeper. By doing so, you will not have to contend with waves or surface current.

First, get neutrally buoyant, look up and around you to assure it is safe to deploy the buoy. Next, unfurl the tube. Unclip the snap or other connector holding the line in place on your spool/reel. Once the line is free to unroll, reconnect the snap to the line where the clip moves freely. Hold the line/spool out in front of you to avoid entanglement. Take a breath of air from your regulator and with your right hand remove the regulator, push open the valve and then blow air through the valve into the tube with your mouth to partially inflate the buoy. Do not attempt to fully inflate the tube at depth. (Remember, the air inside the tube will expand as the tube ascends.) One large breath is usually enough.

An SMB with a tube that’s open on the bottom can be inflated by adding air from the second-stage regulator (or octopus regulator) into the tube. Simply invert the regulator beneath the open tube and depress the regulator purge button briefly.

After rechecking your buoyancy and position, place the line/spool between the thumb and index finger. Be careful not to place your finger inside the center opening in the spool. As the tube is released, keep tension on the line so the tube remains upright.

As you ascend, continue to keep tension on the line. Hold the line in one hand and hold the spool on its side with the other hand. Using a circular wrist motion, roll the slack line onto the spool. Do not attempt to spin the spool to wind the line. Keep tension on the line and wind the spool until all the line is secured as you reach the surface. Use the snap to secure the line and prevent it from unrolling.

Check the area to make sure you’re not in the path of boat traffic, then fully inflate your BC and keep a regulator or snorkel in your mouth. At this time, you can clip the spool to your BC. Continue to hold the inflated buoy until the boat arrives or until you complete your swim to shore.

A safety sausage should be considered an essential accessory item to have with you on every dive. This small piece of gear plays a large role in keeping you safe while enjoying your favorite sport.

Can We Create A Safety Culture In Diving? Probably Not, Here’s Why.

Howard Ratsch — Sun, 21 May 2023 15:17:03 GMT

Can We Create A Safety Culture In Diving? Probably Not, Here’s Why.

by Gareth Lock

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

How do we improve our safety culture in diving? Is it indeed something that we as a community of divers can affect? Human factors coach Gareth Lock argues that there is no magic bullet and, in fact, that the sports diving industry needs to make a fundamental shift in how it manages diver safety, if we are to improve safety. In other words, we still have a ways to go. The retired British Royal Air Force officer explains why.

Use the link below for the complete GUE article

Can We Create A Safety Culture In Diving? Probably Not, Here’s Why. - InDepth (gue.com)

Interview with Hal Watts, Plan Your Dive

Howard Ratsch — Sat, 22 Apr 2023 14:06:17 GMT

Educational Blog

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Hal Watts: Plan Your Dive

Known for his deep air diving exploits back in the day, 86-year-old Hal Watts, aka “Mr. Scuba,” is one of the pioneers of early scuba and credited with coining the motto, “Plan Your Dive. Dive Your Plan.” He founded the Professional Scuba Instructors Association International (PSAI) in 1962, which eventually embraced tech diving, but never relinquished its deep air “Narcosis Management” training. Italian explorer and instructor Andrea Murdock Alpini caught up with Watts and teased out a few stories from the training graybeard.

Please use this GUE link below for the full article. Interview by Andrea Murdock Alpini

Hal Watts: Plan Your Dive - InDepth (gue.com)

What defines a risk? What is involved in taking a risk?

Howard Ratsch — Sat, 18 Mar 2023 18:18:01 GMT

Educational Blog

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

What defines a risk? What is involved in taking a risk?

Difficult questions to answer, because something that feels risky to one person might be yawn-worthy to another. Risk taking, unscientifically, is something you do that gets your blood up, raises your heartbeat, awakens your senses, and makes you hyper-aware of your surroundings.

Surely we can agree that the Covid pandemic has added an unexpected level of risk to everyday life. Add poor drivers, mass shootings, contentious politics, global climate change, and many are left believing that meeting each day is risky enough. But that’s not true for people who identify as risk-takers or thrill-seekers.

“Everyone has a ‘risk muscle’. You keep in shape by trying new things. If you don’t, it atrophies. Make a point of using it once a day.” – Roger Von Tech

There are many activities that go to the trouble of defining the level of risk involved with a specific activity, and while that’s not the purpose of this article, you should know that scuba diving ranks fairly high on the risky behavior scale–higher than skydiving and rappelling. And, cave/wreck diving or freediving isn’t on any risk scale we could locate. We can assume it’s up there—near or at the top.

Please use this GUE link below for the full article by Pat Jablonski

Risk-Takers, Thrill-Seekers, Sensation-Seekers, and … You? - InDepth (gue.com)

FIVE REASONS WHY FISH IDENTIFICATION IS AN IMPORTANT SKILL

Howard Ratsch — Wed, 22 Feb 2023 12:58:52 GMT

FIVE REASONS WHY FISH IDENTIFICATION IS AN IMPORTANT SKILL

By Jill Hottel

Fish Identification and Why it's an Important Scuba Diving Skill (tdisdi.com)

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

WHY IS FISH IDENTIFICATION IMPORTANT?

If you surveyed 100 recreational divers about the top ten most important skills for a diver, I don’t think fish identification would garner many votes. True, finning techniques or navigation may seem more important but don’t discount fish ID – it’s my favorite skill to teach as an instructor. Here are five reasons why you should put the work in to improve your fish ID skills:

1. Fish identification is low and slow

In 2009 I traveled to Manzanillo, Mexico, to become a dive professional. My first instructor there taught me to look for the small stuff. Thus, I learned to dive as close to the bottom as possible without stirring it up…I had to get close to see what I was looking for. Blennies. To do this, of course, I needed to dial in my buoyancy and trim so I didn’t come crashing down onto the reef or drag my gauges across the top. Blennies are cute, odd-shaped bottom dwellers that burrow in the seafloor or inhabit crevices on the reef or rocky substrate. You can find them poking out of their hidey holes, with their mouths agape trying to communicate that you are encroaching on their territory. To me, it looks like they are talking. Perhaps shouting out, “Hey! Did you hear about what went down at the cleaning station the other day?” I like to get close to them…almost nose-to-nose…and say hi. Some species are a mere inch in length, but all of them have an outsized personality.

Fish ID is also slow. If you power fin over the reef, you’ll miss the fish. Not only will you be going too fast to focus on them, you’ll likely startle them by disturbing the water column driving them deeper into the reef or back into their hidey holes. The slower you go the more you’ll see – you’ll be less intrusive moving through the water, and fish will be less startled by you. This also plays to your advantage if you are a photographer, because you’ll have more time to photograph your subjects.

2. Fish ID helps you develop keen observation skills

You don’t have to know the names of the fish to excel, you just have to make observations on their anatomy and distinctive features (i.e., shape, color, pattern) – being able to describe the fish you’ve seen will allow you to effectively describe them to someone else (like the dive guide) or enable you to look them up in your fish ID book. The more you practice, the more you’ll observe, all of which are clues to identifying the fish. What shape is the body…does it have a sloping head, kind of odd-looking, or round like a dinner plate? What stands out…does it have big, juicy lips, or is it primarily red in color? What did you observe about its behavior…is it free swimming or does it hug the bottom?

My old logbook entries are funny because I’d make up names for the fish I’d see – such as black and tans (bicolor damselfish) or LSU fish (fairy basslet). Or I’d write a detailed description of the fish…like the “fish that lies flat and looks like sand” (peacock flounder) or “silver ones/red on back with bulging black eyes sitting in groups of 3-4 weird” (squirrelfish).

3. There’s always something new to see, if you know where to look

There’s a sign in Fife, Scotland, that reads, “Tak tent o sma things” – it translates to “pay attention to the small things.” That’s what I think after I take my giant stride, once I’ve arrived at depth and am beginning my dive. Keep your eyes open, and pay attention to the small things. What do I see? What is unfamiliar? Throughout my dive I keep my eyes peeled – looking under, behind and inside the reef – hoping to spot something new to me…some fish I’ve yet to identify. I never come out of the water disappointed.

Several years ago, I met a diver at his office where he had video footage from a recent dive trip playing. Mesmerized, I asked him about his trip and the diving. Disappointedly, he said he’d never go back there again because he didn’t see anything. “No sharks, turtles. Nothing.” As Mr. T would say, “I pity the fool.”

It’s true, most divers enjoy spotting an apex predator and singing the Jaws theme song to themselves (I’m not the only diver who does this, right?), or watching turtles glide across a reef. But to say that there was nothing to see because you didn’t see a shark or turtle is absurd. There is a seemingly endless array of small marine life to enjoy in our oceans, you just have to look for it. It helps to readjust your thinking by focusing on the abundance of the small things.

4. Fish identification is empowering

You know that feeling when you arrive to a party, walk in and start picking out all the people you know…you get the same feeling when you drop onto a reef and start identifying the fish residents. Not only recognizing them, but naming them. Or better yet, when you’re back on the boat and another diver asks, “what’s the name of that rainbow-colored fish I saw munching on coral and pooping,” and you come in clutch with the answer, “Oh, that sounds like a rainbow parrotfish.” It’s a great feeling to have an answer, and to be able to share your acquired knowledge with a fellow diver. What’s even more satisfying is being familiar with what you see underwater and feeling connected to it. This growing familiarity empowers a diver to want to see and learn more, encouraging them to seek out new underwater experiences.

5. Fish ID is a lifelong pursuit

There are so many fish in the sea that you’ll never know them all. And even if you become an expert fish IDer in, say, the tropical Western Atlantic, you can always travel to the other side of the world and start learning the fish in the Indo-Pacific. While the classification scheme is the same across the globe, you’ll encounter different species depending on where you are. There are always new fish to see, which means you will always be on the perpetual journey of exploration.

SO, HOW DO I GET STARTED WITH FISH IDENTIFICATION?

Fish ID is something you can work on on your own – start with a good fish resource (such as these books from New World Publications) or visit Reef Environmental Education Foundation to view their variety of learning resources dedicated to building your fish ID knowledge. You can also visit your local dive shop and sign up for SDI’s Marine Ecosystems Awareness specialty course. This course will not only cover fish ID for the local area, but also builds a diver’s understanding of marine and freshwater environments, highlights the risks they face, and identifies ways divers can contribute to their conservation.

About the Author

Jill Hottel (Instructor #32568) has been diving since 2000 (that’s more than half her life!). She serves as the executive director of Diving with Heroes, a nonprofit that provides disabled veterans with opportunities to scuba dive. She is passionate about fish ID, and she shares that passion with all her divers. Her favorite fish are the whale shark, yellowhead jawfish, frogfish and (of course) blennies.

Cardio and diving

Howard Ratsch — Mon, 23 Jan 2023 19:00:31 GMT

Trouble at 100 Feet | Lessons for Life

A medical emergency underwater puts a diver in crisis.

By Eric Douglas April 16, 2021

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Ted was stoked to begin his training as a rebreather diver. He had been working toward this goal for several years, building up his dive experience and researching the best unit for his needs. Now he was nearing the end of his first tec closed-circuit rebreather diving course.

He was a bit uncomfortable, struggling to catch his breath, but he chalked it up to nerves and getting used to the closed-circuit device.

The Diver

Ted was a 51-year-old male and an experienced, certified diver. He had reached a personal income level that allowed him to travel more. He wanted to up his dive game by learning to dive with a rebreather system. He looked forward to the extended bottom time the device provided, along with the ability to move silently through the water. As an avid underwater photographer, he hoped it would help him get closer to sea life so he could capture critters in their natural state.

A year earlier, he had consulted a local dive instructor about what he needed to do to get rebreather certified. Since then, he had been working toward the goal, logging hours underwater and practicing his diving skills.

The Dive

After reviewing the techniques unique to diving a rebreather system in a pool, Ted, his dive buddy and their instructor made their way to open water for a series of checkout dives. Conditions were good on the ocean as they entered the water from a local charter boat that was accustomed to working with technical divers.

The boat and its crew didn’t have a problem with them making long, deep dives, and everyone on board was a tec diver. Ted’s group planned the dive for 90 minutes at a max depth of 130 feet of seawater. They made their way gradually toward the final depth, descending along the reef structure.

The Accident

The divers had been in the water for 45 minutes, slowly making their way to their planned maximum depth. At 97 feet, Ted began struggling to breathe. He signaled that he was having trouble with his rebreather unit and indicated he needed to ascend to the surface.

One hard and fast rule of technical diving is that any diver can call any dive for any reason.

When Ted indicated he was having a problem, the instructor immediately agreed that they should end the dive. All three divers began ascending toward the boat. On the way, Ted lost consciousness. The group had obligatory decompression time, but they ignored it and continued toward the boat to get Ted the help he needed.

The boat crew immediately began lifesaving procedures, but Ted could not be resuscitated.

Analysis

An after-accident analysis of Ted’s gear indicated his rebreather system was working normally. The equipment wasn’t to blame for this dive accident. Although the group omitted decompression on the way to the surface, that wasn’t the cause of this accident either. Ted’s problems began at depth. Neither of the divers with Ted exhibited any symptoms of decompression sickness because of the omitted decompression, although they did not return to the water and were observed for the rest of the day to make sure no problems arose. After performing an autopsy, the medical examiner determined that Ted had a cardiac event underwater. He had dilated cardiomyopathy, hypertensive heart disease (high blood pressure) and coronary atherosclerosis (hardening of the arteries). He was also obese and had a medical history of sleep apnea. A dilated cardiomyopathy is a weakening of the heart’s primary pumping chamber, the left ventricle. This can be caused by a variety of conditions, including coronary artery blockages, long-standing high blood pressure, diabetes mellitus and viral infections. In fact, in a large percentage of cases, doctors are unable to determine the underlying cause of the condition. Regardless of the cause, this weakening of the heart muscle can result in a multitude of problems, such as fatigue, shortness of breath and life-threatening heart-rhythm abnormalities .There is a special concern for divers with dilated cardiomyopathy. When humans are immersed in water (swimming or diving), there is a fluid shift of about 700 cubic centimeters (about 1.5 pints) from the periphery to the central circulation. In patients with dilated cardiomyopathy, this additional fluid load might not be tolerated by the heart, resulting in symptoms of severe shortness of breath from congestive heart failure. While we will never know for sure, this is probably what happened to Ted.In preparation for learning to use the rebreather system, Ted spent a lot of time diving and working on his underwater skills. He also studied the physics of mixed gases. What he didn’t focus on was the physiology of diving and preparing his body. What is important to remember is that diving, be it on open-circuit scuba or a rebreather, puts additional strain on the body. Water provides more resistance than air, so your body has to work harder to move. Your breathing is somewhat restricted, and you might need to exert yourself if, for instance, you are caught in a current and have to swim harder to get back to the boat. Additionally, having a cardiac event underwater or on a dive boat makes it much more difficcult to get to emergency medical care. At your local mall, you can expect to receive bystander care within moments. Emergency medical services will likely arrive with a full range of equipment and medicine to stabilize you before you get to the hospital, likely in less than 10 minutes.

On a dive boat, even with the best-trained crew available, there will be delays getting you out of the water and out of your gear before care can begin. And then there are longer delays getting you to advanced medical care. We don’t know if Ted knew about his heart condition; it’s likely he did not. His doctor had diagnosed him with high blood pressure and sleep apnea, but Ted wasn’t controlling either condition well. All of that reinforces the importance of being physically fit for diving. Ted was 51 years old, but his medical history indicates that he probably should have had a conversation with his doctor about diving and what those conditions meant to his overall health. During his year of preparation for technical diving, he should have spent more time training himself physically and managing his health complications.

There is a possibility that if Ted had been given a stress test, an echocardiogram and a complete physical, a diving physician would have told him he should consider giving up diving. While that choice might be unthinkable to some, the idea of dying on a dive boat, putting your dive buddy at risk in the process, is inarguably worse.

Douglas Ebersole, M.D., consulted on this column. He is an interventional cardiologist at the Watson Clinic in Lakeland, Florida, and the director of the Structural Heart Program at Lakeland Regional Health Medical Center. Additionally, he is a cardiology consultant to Divers Alert Network, as well as an accomplished diver and closed-circuit rebreather instructor.

Lessons for Life

Stay fit for diving. Exercise regularly, and manage your weight.
Taking medication does not necessarily prevent you from diving. Rather, the underlying condition the medication is intended to treat is the concern.
Consult a physician familiar with diving to ensure you are fit to dive, especially if you have any medical conditions thought to be a contraindication.

History of the 80 cuft tank

Howard Ratsch — Thu, 22 Dec 2022 16:31:15 GMT

Educational Blog

A Brief HISTORY OF SCUBA’S Ubiquitous Aluminum 80 Cylinder

By Mark Gresham and Bill High.

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

The “80” had a down-side. At 3,000 psig/207 bar, that pressure was a bit high for most compressors in use. Many dive stores could not fill them completely. More importantly, its diameter was slightly greater than the common steel cylinder, so it would not fit into the non-adjustable backpacks.

Alcan (Luxfer) was not the first to make an aluminum scuba cylinder. In the mid-fifties, the US Navy purchased many aluminum cylinders from Pressed Steel Tank Co. which were not Interstate Commerce Commission (ICC) approved for commercial use. Those cylinders were made by a spinning process that required a plug to close the round bottom. By the 1970s, some of those cylinders found their way into recreational diving; however, they were illegal to fill or transport.

For several years, the Luxfer “80” was the only kid on the block. In 1981, the competitors Walter Kidde Co. and Catalina Tank Co. began making competitive cylinder models using the somewhat different alloy, 6061.

The bright future for the “80” continued into the 1980’s. Adjustable backpacks solved the size issue. Corrosion resistance was evident. Several colors were available. There were two things we did not know. First, in 1982 and 1983, Luxfer produced its cylinders using the 6351 alloy with a somewhat elevated trace lead content. That became an issue later. Catalina and Kidde continued using 6061 alloy. Secondly, a metallurgical issue raised its ugly head.

For the complete GUE article, Please use the link below

A Brief History of Scuba’s Ubiquitous Aluminum 80 Cylinder - InDepth (gue.com)

Going Deep

Howard Ratsch — Tue, 22 Nov 2022 22:30:07 GMT

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Going Deep

By Jon Hardy

Setting the Stage

Jerry was an occasional diver who made most of his dives when traveling on vacation. Being single, he usually traveled alone, but sometimes a non-diving friend joined him.

While on an island vacation, Jerry found a dive operator offering a mid-week deep dive to an offshore rock pile that featured black coral and rare fish. Although Jerry had not been diving recently, when the dive operator asked about his dive experience, Jerry implied that he had much more experience than he actually did and signed up for the advanced dive.

The dive plan was first to anchor the boat in the sand beside the rock pile. Next, after a thorough briefing, the divemaster would lead the six divers down the anchor line, and then put a lift bag on the anchor to make retrieval easier. The divers would then explore the site. After 10 minutes in warm, clear, calm waters, ranging in depth from 135 to 150 feet, the group would proceed up the anchor line, making a decompression stop and a safety stop, and then head back to the boat. A hang tank would be provided at 15 feet in case anyone ran low on air during the stops.

The Dive

The first sign of difficulty came when Jerry arrived at the dive store the morning of the dive. The divemaster for the trip discovered that Jerry needed to rent much of his gear and that he had no dive computer. Then, on the trip out, the divemaster thought that Jerry's excessive chatter about dives he had made did not ring true. But, by this time, the divemaster felt he needed to press on with the dive.

The anchoring and briefing went as planned, although the current was stronger than the divemaster had planned for. Descending on the anchor line was a bit more work than expected, but all the divers arrived on the bottom, gave the OK sign and proceeded to explore the near side of the rock pile, which was the lee side, out of the current. Meanwhile, the divemaster set the anchor and attached the lift bag. Jerry had swum off to the deeper end of the rocks at 145 feet, but was still in view.

After a couple of minutes, when Jerry had not returned to the group, the divemaster swam to him and found him motionless, unconscious and not breathing. The divemaster grabbed Jerry, towed him to the anchor line and started to ascend, abandoning the other five divers.

Because the current was strong and Jerry was not breathing, the divemaster skipped the stops. As soon as they were on deck, CPR was started. Efforts to revive Jerry failed, and he was pronounced dead at a local hospital.

Analysis

What most likely befell Jerry is known as deep-water blackout, a little understood and fortunately relatively rare accident. Deep-water blackout most often occurs during dives beyond 130 feet on air, and to divers with little or no experience in the particular demands of this type of diving. Deep-water blackout may be related to fitness, narcosis, gas density, carbon dioxide retention and breathing resistance, but none of this is clearly understood.

Lessons for Life

Scuba diving takes practice to keep skills fresh. Refresher and advanced courses are ideal for this.
Be honest with yourself and others concerning your diving experience.
Do not engage in deep or decompression diving unless you have the training and experience to do so. Some training agencies now offer training in extended-range diving--diving beyond the usual recreational limits.
If you are going to make serious or demanding dives, you should have your own high-performance regulator, instruments (including both a dive computer and a compass) and BC.

Don't Panic

Howard Ratsch — Thu, 20 Oct 2022 23:24:59 GMT

Educational Blog

This article represents the views of the authors. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

DIVING SAFETY

Don’t Panic: Understanding the Causes and Remedies of Diver Panic

The “Hitchhikers Guide to The Galaxy” summarized it neatly: Don’t Panic! For good reason: taken together panic/anxiety/stress have been ranked as one the top three risk factors in scuba diving incidents. Here clinical psychologist and scuba instructor Laura Walton dives into the definition and causes of panic, explains why seeking to avoid panic can make matters worse, and offers effective strategies to consider.

A handful of studies suggest that as many as a quarter to a half of qualified (i.e. open water or higher) recreational divers have experienced panic or near-panic on at least one occasion (Colvard & Colvard, 2003; Morgan, 1995).

Please use this GUE link below for the full article by Laura Walton

Don’t Panic: Understanding the Causes and Remedies of Diver Panic - InDepth (gue.com)

Sustainable Tourism and Diving: Tips for Treading Lightly

Howard Ratsch — Thu, 22 Sep 2022 22:07:08 GMT

Sustainable Tourism and Diving: Tips for Treading Lightly - Dive Training Magazine (dtmag.com)

This article represents the views of the authors. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Sustainable Tourism and Diving: Tips for Treading Lightly

Story by Alex Brylske

November 20, 2019

If you’re a diver, here’s a little tidbit I’ll wager you’re completely unaware of: Did you know you’re an “adventure tourist?” Indeed, you are — at least according to the travel industry. In fact, scuba diving and snorkeling are specifically listed as adventure travel activities by what may be the top expert in the field — the Adventure Travel Trade Association. They define an adventure tourist as anyone engaged in a travel experience that involves at least two of three elements: 1) physical activity; 2) the natural environment and 3) cultural immersion.

But before venturing further on the adventure tourism path, let’s look first at travel and tourism in general. In terms of both direct and indirect impacts, tourism is a major contributor to the global economy. The international tourism industry generates nearly one trillion dollars annually and comprises 30 percent of the world’s exports of commercial services (six percent of total exports). According to the World Travel and Tourism Council, it accounts for more than nine percent of global Gross Domestic Product (GDP) and employs one in every 10 people on earth. By comparison only three other industries rank higher in global export: fuels, chemicals and automotive products. And it’s growing.

The scuba diving industry is an excellent example of how tourism has grown in recent years. In fact, it has changed fundamentally. Once driven by scuba equipment sales it’s now driven by travel. For example, at 19 billion dollars in revenue annually, dive travel now accounts for more than six times the revenue generated by dive equipment sales.

But you’re not in the diving or tourism business. So, why should you care? The reason is simple. The dollars quoted in all those statistics are your dollars. Thus, you have a very big voice in how, where and on what that money is spent. In other words, you have enormous power to influence the future direction of the travel industry, generally, and the dive travel industry, directly. More importantly, your dollars don’t just contribute to the financial success of whatever travel provider you choose. If you choose wisely, your dollars can also have a positive impact on the quality of the destination you visit and on those who live there.

So, what’s the problem? Well, it turns out that tourism can be a double-edged sword. In many ways it has the potential to be a victim of its own success.

International tourist arrivals (overnight visitors) now exceed a billion per year — millions of which are scuba divers. That’s equivalent to the entire population of China and the numbers are expected to increase to nearly two billion by 2030. So, it’s hardly surprising that at destinations where their bread and butter is a natural resource (like coral reefs), the impact from tourism can range from harmful to devastating. Yet, tourism can be done responsibly and actually become a positive force for conservation, if — and that’s a big “if” — it’s done right. It’s up to you. As one travel expert has puts it, “Tourism is like fire — it can cook your meal, or it can burn your house down. The choice is yours.” Preventing the fire of tourism from getting out of control is the biggest challenge facing the travel industry today because some popular destinations around the world are being literally “loved to death.” This phenomenon even has a name — over tourism.

When it comes to the environmental consequences of over tourism, marine tourism is perhaps the sector most affected of all nature-based travel activities. As a major share of marine tourism takes place in the tropics — and what draws folks there is the environment — it doesn’t take a genius to realize that much of marine tourism is wholly dependent upon healthy coral reefs and associated ecosystems (seagrass beds and mangrove forests). And surely there’s no segment of tourism more dependent on the continued existence of healthy coral reefs than scuba diving.

Of course, tourism isn’t the primary reason for the demise of earth’s coral reefs. And though factors such as destructive fishing practices, pollution, coastal development and climate change are far bigger problems, tourism does play a role. However, the reason reefs at popular dive destinations are in trouble isn’t from what you might assume. When talk turns to how coral reefs are degraded at popular tourist sites, divers are often viewed as the culprits. After all, our high visibility and close association with coral reefs makes us easy targets. Without question, anchors as well as clumsy and careless divers do take their toll on our beloved reefs. And the overabundance of divers on any reef, regardless of their behavior, will have a negative impact. But this problem pales in comparison to other destructive factors.

A colleague of mine once summed up the problem quite accurately. “A diver,” he contends, “probably does more damage to a coral reef by flushing the toilet in his hotel room than he’ll ever do by diving on one.” It was a glib but astute insight into the real problem. From a tourism perspective, the concern is less about direct damage from recreation activities like diving and boating, and more about the indirect threats from the infrastructure needed to support tourism. Every tourist needs a place to eat, sleep and go to the bathroom. They also prefer that these facilities be very near or, ideally, on the water. In addition, every tourist demands the facilities and services that make tourism possible, such as beaches, docks and marinas. These all add to the eutrophication, pollution, demand for seafood and sedimentation problems already threatening reefs from local population pressure (a population pressure that’s sometimes driven by tourism). And considering that on small islands, tourists can sometimes outnumber the local residents, it’s easy to understand the validity of my friend’s “flushing the toilet” assertion.

While the environmental consequences of tourism are often obvious — at least for those willing to take a closer look — there are other not-so-obvious results that involve people. Clearly, the consequences of a rapidly expanding tourism industry have, at many destinations, been as detrimental to societies as it has to the physical environment. For instance, many developing countries’ job opportunities in tourism have encouraged the migration of people to tourism centers, often disrupting or outright destroying traditional ways of life. Already some communities and cultures have been completely displaced or destroyed by a booming tourism trade. This social upheaval can lead to problems with crime, pollution and a general erosion in the fabric of society. Ironically, this can lead to the decline in the appeal of a destination because it no longer feels “authentic” to travelers, thus killing the golden egg-bearing goose.

This phenomenon is, in fact, so common and well-studied that it even has a name — the Tourism Area Life Cycle (TALC). The TALC cycle views tourism as a dynamic process where destinations go through predictable successive stages. It starts when a relatively undeveloped location initially attracts a few adventurous tourists seeking pristine nature and indigenous cultures. Then, as tour operators and related businesses recognize the market potential of the location, the local tourism industry rapidly expands and develops. However, the changed nature of the now “discovered” destination causes the type of tourists who were initially attracted by the undeveloped nature of the location to move on to other destinations that remain undeveloped and pristine — and the cycle is repeated.

But there’s nothing inevitable about this cycle. By recognizing the cycle of over tourism and unsustainable tourism practice soon enough, destinations can reverse the downward spiral. Corrective actions can be taken, such as limiting tourist numbers, establishing marine protected areas, improving infrastructure codes or restricting certain destructive practices. Ideally, the entire tourism paradigm can change, but this calls for a different kind of tourism: Sustainable tourism.

Sustainable Tourism: A New Paradigm

The problem is that undiscovered tourism destinations are not unlimited. As a popular protest poster tells us, “There is No Planet B.” Tourism has become so big that we have almost run out of truly pristine locations. So, without the option of creating more places on earth, the only reasonable alternative is conducting the business of tourism in a different way — and that’s exactly what’s beginning to happen all around the world. Tourism, and tourists, are changing for the better. So, let’s look at how.

Traditionally, the reason for travel has been to rest and relax. In the marine sector, this emphasis on leisure is referred to as “sun, sea and sand” tourism. This describes the bulk of marine tourists and probably always will. But over the past few decades there have been some significant changes. Increasingly, tourists want more from their holiday than a suntan and souvenirs. These more intrepid travelers — I’ll no longer call them tourists — want a closer and more experiential encounter with the destination they visit than lying on the beach during the day and partying at night. For many, the primary motivation for selecting a destination is not the quality of its beaches, golf courses or of night life, but its healthy natural environment and undisturbed culture. In the words of one tourism expert, “An increasing number of travelers today want holiday experiences that are authentic, immersive and self-directed.” And what’s good news for us is that’s almost the perfect definition of scuba diving.

The other good news is that, while the travel and tourism industry is sustaining a healthy grow of five to seven percent annually, the adventure and nature-based travel industries are growing in the 20 to 30 percent range. And even more significantly, these travelers most often understand, in fact prefer, to travel responsibly. Of course, this hasn’t gone unnoticed by many within the travel industry and has already led to massive changes in the travel products offered by many destinations and how they’re marketed.

The evolution of adventure travel can be traced to early attempts to meet the demand of changing attitudes toward tourism, which led to the development of the ecotourism industry. From this evolved the idea that travel should not only serve the tourist but the destination and its inhabitants as well. As ecotourism became more mainstream, newer and more authentic directions were explored and the market segmented into many more specialized sectors and activities. Then, with the growing recognition of the declining state of earth’s environment, many in tourism began to realize that making tourism more accountable to both the local environment and residents could no longer be just a specialized endeavor targeted to “tree-huggers.” All forms of tourism should become part of the solution and not part of the problem. From this movement was born the idea of “responsible tourism,” or what’s become better known as “sustainable tourism” — an off-shoot of the growing concern for sustainable development.

CLICK HERE TO DOWNLOAD OUR SUSTAINABLE TOURISM CHECKLIST

But what exactly does sustainable tourism really mean? While arguments rage among the experts in the field, one of the best functional definitions has been offered by those who have been involved in international tourism since its inception, Caribbean islanders. According to the Organization of Eastern Caribbean States, sustainable tourism is defined as “the optimal use of natural and cultural resources for national development on an equitable and self-sustaining basis to provide a unique visitor experience and an improved quality of life through partnership among government, the private sector and communities.” Importantly, this definition recognizes that tourism isn’t just an economic activity. As it has both environment and cultural consequences, so too must it take into account, and be responsible for, its effects. This ethos is exemplified in the commonly used sustainable tourism mantra “people, planet, profit” or what some have termed the “triple bottom line.”

In general, sustainable tourism has six underlying goals. These include: minimizing environmental impacts; improving local contribution to sustainable development; protecting the quality of the environment by maintaining biological diversity and ecosystem function; minimizing the use of non-renewable resources; ensuring cultural integrity, local ownership and social cohesion of the community; and last, but certainly not least, providing a high quality experience for tourists.

Today, savvy tourism operators trying to cater to the new, more environmentally and socially conscious traveler have a daunting task. No longer can they be satisfied by having the nicest hotel and restaurant or best beach or even the most exciting tours. Study after study has shown that many travelers today — a majority of European and a fast-growing number from the U.S. — are just as or more concerned with the environmental and social footprint of their travel provider as they are with the actual product. So, travel providers and destinations today aren’t turning to sustainability because it’s a nice thing to do for the earth or future generations. They’re doing so because it makes business sense and realize that not to do so will at some point will mean they’ll no longer be in business.

So, What Can You Do?

My experience has been that divers are a special breed. The most serious among us are anything but tourists — we’re travelers. We take very seriously our responsibility to protect the environments we visit and are increasingly recognizing that our travel demands are sometimes placing undue stress on local ecosystems and cultures. So, what we can do to help ensure that operators and destinations hear our wishes loud and clear to make tourism more sustainable is simple. As I indicated at the beginning, we can vote with our wallets. When making your choice of what destination and operator to patronize, take a few minutes to consider not only what you might “get for your dollar,” but how that destination or operator does business and reward those who are doing it right. In that way, you can become part of the solution and help drive a process that will make tourism a positive force for change. Let’s use the fire that we helped ignite to create a warm glow — not burn our house down.

Diving at Night

Howard Ratsch — Mon, 22 Aug 2022 19:02:35 GMT

Educational Blog

More Than Darkness: Human Factors and the Night Diver - Scuba Diving News, Gear, Education | Dive Training Magazine (dtmag.com)

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

More Than Darkness: Human Factors and the Night Diver

By Robert N. Rossier

It’s like taking a stroll downtown at night,” said our instructor, Don. “Everybody is out — a really wild time.” Waving his arms in animated motion, he proceeds to describe the reef-city after dark. “You’ve got corals and tubeworms dancing to the tune of the tides, tentacles swaying in the gentle current. A parrotfish is curled up on the corner in its translucent sack, trying to sleep it off, while gangs of crustaceans cruise the dark corners of the reef’s back streets. And the city lights are a thing of beauty — a soft glow of bioluminescent algae and comb jellies. But like taking a stroll through the city at night,” he warns, “you’ve got to be careful, take precautions. After all, it’s a different world down there at night.”

When you first hear about night diving, that’s the focus — the difference in the marine life at night. But how about us, the divers? Are we different, too? At first blush, night diving might not seem like such a big deal. It’s dark, so we use dive lights. No problem, right? But nothing is that simple in diving.

In reality, some very important differences distinguish day from night diving. Diving at night introduces an entirely new regime of human factors considerations that affect our physiological, psychological and biomechanical adaptation to the underwater environment. By understanding these human factors considerations, we can improve our aquatic decision-making and safety in the water after dark.

Aquatic Decision Making

At the core of our ability to dive safely is our judgment and decision-making ability. To exercise good judgment and make safe aquatic decisions requires a continuous assessment of three vital factors: the environment, our equipment, and our own abilities and limits. Training and experience are key elements in making these assessments, but our experience and training in daytime diving does not necessarily prepare us for a night excursion under the waves. Each of these factors takes on new dimensions as daylight fades and shadows grow longer. Water conditions and diving environments considered within our abilities for a day dive become much more difficult to negotiate at night. Our familiarity with our equipment becomes more critical when diving in darkness, and additional equipment is needed to ensure proper vision, communication and navigation, both underwater and on the surface. Finally, our own abilities and limits vary much like the daily cycles of day and night.

The Rhythm of the Night

One of the first implications in night diving is the effect of our circadian rhythms, our daily sleep-wake cycles that alter our states of consciousness. Body temperatures, blood pressure, stress hormones, digestive secretions and mental alertness all follow a daily pattern that resets itself according to daily cycles of sunlight and darkness. Of these, mental alertness may well be the most important to a diver, as it affects our decision-making ability.

According to experts in the field of circadian science, a person rising at 7:30 a.m. with adequate sleep will experience peak alertness levels in the morning around 8 to 9, and again in the evening between 7 and 9. (See Figure 1.) Alertness drops to a lower level from about 12 noon to 3 p.m. and drops off rapidly after 9 p.m. Based on this data, divers can generally expect reduced mental alertness on a night dive. The excitement of a night dive might conspire to artificially elevate mental alertness, but other factors, including acute and chronic fatigue, may also come into play.

The effects of fatigue on human performance have long been known and understood. Acute or short-term fatigue is the tiredness experienced after long periods of physical or mental strain. Work, study, travel, lack of sleep and physical exercise can induce episodes of acute fatigue. The symptoms include reduced coordination and impaired alertness, both of which can be problems for divers. If a diver works, plays or parties too hard over a period of several days, the effects of acute fatigue can significantly degrade his or her performance and safety on a dive.

To illustrate the importance of mental alertness, consider the fact that 32 percent of marine accidents occur between the hours of 4 a.m. and 8 a.m. It’s also interesting to note that four of the worst industrial accidents in recent history involved impaired judgment caused by fatigue. The Chernobyl and Three Mile Island nuclear power plant accidents, the grounding of the Exxon Valdez off the coast of Alaska and the Bhopal, India, chemical plant leak all occurred between midnight and 5 a.m. — a period when mental alertness is at its lowest.

One approach to minimizing the effects of reduced mental alertness is to carefully plan and prepare for night dives. By making night dives relatively simple and conducting them in low-risk environments, we can also reduce the potential for problems.

Circadian rhythms and fatigue aren’t the only human factors challenges faced by night divers. Night diving also presents a number of physiological and biomechanical considerations, including nutrition, night vision adaptation, heat balance and increased task loading.

Nutrition: A Diet for Night Diving

Nutrition is an important consideration for divers regardless of when they dive, but nutritional strategy is particularly important at night, when we strive to overcome the effects of circadian rhythms and fatigue. Scientists and nutritionists have learned that good nutrition and eating habits play an important role in mental performance. The types of foods eaten and the sequence in which they are consumed have a marked impact on our state of mind, mental alertness and reflexes.

Chemical neurotransmitters derived from the foods we eat help transmit messages to the brain, causing a response in terms of mental acuity and activity. Seratonin, a chemical neurotransmitter derived from carbohydrates, tends to have a calming, relaxing effect on mental activity. While this can help reduce stress, too much of a good thing can be bad. A high-carbohydrate meal consisting of pasta, crepes, potatoes, starchy vegetables and sweets can increase seratonin levels enough to induce not just a pleasant feeling, but lethargy and the need to sleep. Likewise, fats tend to prolong digestion and rob the brain of blood to aid in the digestion process. The result is fatigue, sleepiness and overall lack of alertness.

Alternatively, a meal that begins with high-protein foods, such as steak, eggs and high-protein cereals and is relatively low in carbohydrates and fat, will help promote mental alertness. Dopamine and norepinephrine, derived from protein in our food, stimulate the brain to higher levels of alertness and activity.

Most divers are savvy enough to avoid alcohol prior to a night dive. Alcohol affects both the central nervous system and the circulatory system in ways that can erode the margin of safety when diving. Even a small amount of alcohol can degrade mental acuity, increase heat loss and predispose a diver to decompression illness. (See sidebar.) When planning a dive after dark, it’s best to stay away from the bar.

Night Vision Adaptation: Seeing Isn’t Always Believing

As most divers would agree, the most obvious difference between a day dive and night dive is our inability to see as well at night. Ambient lighting in daylight allows us to see clearly, and our peripheral vision is limited only by the physical constraints of our mask. At night, our vision is limited by the beam of our dive light. This tends to focus our attention on a relatively small area of the submarine world, but it has other consequences as well.

Surprisingly, we can often see significantly more than we might expect even without the aid of a dive light, although vision at night without artificial light may not be quite so clear. The retina of the human eye has two types of receptors, referred to as cones and rods. The cones are located in the central area of the retina and provide clear, focused vision in well-lighted conditions. The rods, located in the area surrounding the cones, see less clearly, but more readily adapt to dark lighting conditions. “For more information, see “Understanding and Equipping for Underwater Vision” in the June 2000 issue.”

Our best night vision develops after a period of exposure to low lighting, a process called dark adaptation. This can take as long as 30 minutes for total adaptation to blackness, but 20 minutes in dim red lighting will provide a moderate degree of adaptation. Dark adaptation is impaired by the carbon monoxide present in cigarette smoke, or a dive boat or compressor exhaust.

Even a brief exposure to white lights will require a lengthy adaptation process to restore night vision, so be careful not to shine a dive light in another diver’s eyes. Night vision may also be impaired for some time after submerging from a brightly lit environment.

Reduced visual perception can manifest additional problems on a night dive. Pilots have long been taught that various visual illusions, disorientation and vertigo can occur in a darkened environment. The sense of balance and motion is derived from several sources, including visual references and the intricate mechanisms of the inner ear. Normally, the brain compares inputs from various senses to determine orientation and movement.

Without all the necessary information, the brain can become confused, causing the individual to take inappropriate actions. For example, certain accelerations caused by rapid head movement, turbulence or changes in aircraft orientation combined with limited visual references can induce spatial disorientation or vertigo in pilots. If unaware of the problem, a pilot might put his aircraft in a dangerous position while attempting to rectify an incorrectly perceived problem. In these situations, pilots must rely on the aircraft instruments to determine the orientation and true motion of the aircraft. A failure to rely on or properly interpret flight instruments combined with the lack of visual references can cause a pilot to fly a perfectly good airplane into the ground.

For divers, a lack of visual references combined with rapid head movements, currents or surge can also create false perceptions of motion and orientation. Head-first descents in dark or limited-visibility water, even with a dive light, can result in disorientation and vertigo. (See sidebar.) When the beam of our dive light is scattered or reflected during a rapid descent, the effect can be similar to driving at night in a blinding snowstorm, and disorientation and vertigo can result. To reduce the effect, make a slow, controlled, feet-first descent when diving from a boat or in open water. Following a descent line or anchor line and monitoring a depth gauge or computer during the descent virtually eliminates the vertigo and disorientation.

Perhaps more importantly, a lack of visual references on the ascent can lead to disorientation and excessive ascent rates. Again, avoiding this problem on a night dive is relatively simple. On a shore dive, we can maintain contact with the bottom throughout a gradual, controlled ascent. When diving from a boat or surfacing in open water, a good option is to use an ascent line and closely monitor the depth gauge or dive computer to maintain a proper ascent rate.

What’s Hot and Who’s Not

While the water temperature might in fact be the same day or night, several factors tend to increase our heat loss on a night dive. The air temperature is likely to be lower at night than during the day, possibly leading to greater heat loss prior to and following a night dive. In addition, we have no sun to warm us before, between and after night dives.

It’s not unusual to begin a night dive with a heat deficit from the day’s diving, particularly if we haven’t taken the time to get the proper rest, warmth and nutrition following the day’s diving. Experts warn us that it is quite possible to “feel” warm, even if our core temperature is reduced.

In his book Deeper into Diving, author and lecturer John Lippmann states, “Divers often disregard cumulative effects of repetitive diving. After the initial dive, the diver might experience superficial skin warming and thus feel warmer. However, his core temperature may still be reduced. Feeling warm is no guarantee that your heat losses have been replaced. The best way to show that your heat losses have been replaced is to start sweating. This shows the body needs to lose heat.”

Don’t make the mistake of considering heat loss merely a matter of comfort. As with nutrition and fatigue, body temperature has a direct effect on mental processes. If body temperature decreases significantly, judgment might be jeopardized. In addition, breathing rate may increase in response to cold, causing a diver to consume air reserves more quickly.

“Cold-induced mental changes are probably the danger to the diver,” writes Lippmann, “because once the brain does not work properly, wrong decisions can easily be made. Some authorities believe that long, slow cooling of the body does not stimulate shivering and the subsequent heat regeneration. As a result, the diver might not notice the heat drain from his body until significant hypothermia has developed and shivering finally occurs. Some consider this ‘silent hypothermia’ to be the major hazard to the diver in cold water, as it will make the diver more accident-prone without him being aware of it.”

The take-home message for night divers is to minimize heat loss. Precautions against heat loss may include wearing extra exposure protection on all dives prior to a night dive, even in warm waters. We can limit our cold exposure prior to night dives by limiting bottom time and depth. Limiting bottom time reduces the period during which the heat loss is high, and limiting depth minimizes the compression of the exposure suit, thus improving its performance. Changing into warm, dry clothing between dives can reduce evaporative cooling.

Task Loading and the One-Handed Diver

Beyond the physiological considerations of a night dive, we must also contend with a basic biomechanical handicap. The simple act of using a hand-held dive light means that we have only one free hand. Buoyancy control, ear clearing and communications must be accomplished “single-handed.” While not necessarily a problem, the difficulty can increase dramatically when towing a surface float or manipulating other accessory equipment.

The single-hand limitation can become a significant handicap, even when contending with relatively minor equipment problems. As Dr. Glen Egstrom, Professor Emeritus UCLA Department of Physiological Sciences, explains, “We typically use one hand to hold the dive light, and this becomes a problem in an emergency situation. If we drop the light so we can deal with the problem two-handed, we can no longer see.”

The Psychology of Night Diving

Divers are drawn to night diving like moths to a porch light, and there’s really little surprise. Just the thought of venturing into the water at night can make your skin tingle with excitement. Entering a world illuminated only by a dive light, our attention is drawn to a sharp point of focus, and we find ourselves seeing the underwater world as if for the first time. “We have an entirely different psychological set at night,” notes Egstrom. “First, there’s a peripheral narrowing that occurs as we increase the psychological stress. It becomes a more introverted dive, and this is actually something that people enjoy. The dive takes up more of our cognitive energy.”

Indeed, there are stresses associated with a night dive. Perhaps the most obvious is the psychological stress of facing the unknown, and this can last from the planning phase throughout the entire dive. If we’re unfamiliar with the area, night diving procedures or the nature of marine life that might be encountered, our stress levels are certain to be heightened. Add unfamiliar equipment, a new or different buddy, or any other factors, and our baseline stress for a night dive can be significant.

While a low level of stress when diving can be helpful in focusing our attention on the situation at hand, too much stress can spell trouble. As stress increases further, our ability to maintain situational awareness decreases, degrading our ability to make the assessments necessary for safe, competent decision making. Increased stress may also translate to increased breathing rate, making air reserves a more critical consideration.

A number of situations that bump up our stress level quite abruptly can arise on night dives, especially if we’re unprepared. One of the thrills of night diving is having unexpected sea creatures suddenly loom out of the darkness. But sometimes this surprise factor creates a momentary heightening of anxiety and stress. A minor equipment problem or disorientation can also spike the stress level until the situation is resolved.

The flip side to the enjoyable, introverted dive is a reduced situational awareness that erodes our decision-making ability. As Egstrom explains, “Since the peripheral visual field contracts during periods of increased stress, we lose a lot of information we might otherwise have.” Sometimes divers become so engrossed with their surroundings at night that they fail to closely monitor their depth or air consumption.

The real problem comes when a situation begins to run awry. “At night, we might not be as likely to see a problem developing,” suggests Egstrom. “So this narrowing of focus can be a problem when it comes to our buddy.” If a situation is left unchecked, a full-blown emergency can develop, throwing divers into a dangerous spiral that runs out of control. An emergency that arises during the course of a night dive can elevate stress beyond the levels expected for a similar scenario in daylight. For example, a low-air or out-of-air situation may be more stressful at night due to the difficulty of resolving the problem in darkness. The net result may be an inability to successfully complete the necessary task.

For this reason, divers must focus on situational awareness and keep tabs on their buddy during a night dive. By staying in a fixed position relative to one another, divers are less apt to become separated and can communicate more readily. By following such a protocol, the stresses that might develop can be minimized, and the potential for problems is greatly diminished.

Training and Fitness

The real keys to safe and enjoyable night diving are training and fitness. Proper training in night diving skills and procedures, combined with a regular program of fitness, form perhaps the best strategy for mitigating any negative human factors considerations associated with night diving.

Night diver training focuses sharply on the night environment, skills, and the planning and preparation needed to safely conduct a night dive. All these topics are covered in a night diving specialty course. The more we know about night diving and the environment in which we’re diving, the more confidence we have in our abilities to dive safely. This confidence helps shield us against the effects of psychological stress.

Proper planning and preparation go a long way toward avoiding disorientation, vertigo and potential emergencies. Start by preparing a detailed emergency procedures plan and review the elements of this plan before entering the water. The emergency plan should consider such contingencies as low air, out of air, entanglement, missing buddy, disorientation, failed dive light(s) and other typical equipment problems.

To compensate for reduced mental alertness and the obvious difficulties of working in darkness, our strategy should be to prepare as much of our gear as practical during daylight hours, when our mind is alert and it’s easier to spot problems. This leaves only the process of suiting up and completing the necessary checks and safety briefings to be done prior to entering the water.

When an unplanned situation arises on a night dive, our response should be to stop, relax, breathe normally and follow the established procedures developed as part of the predive planning. If the situation lies beyond the established emergency plan, we must think rationally and communicate before launching into an action that might be unsafe.

A critical aspect of night diver training is practicing the requisite emergency skills and drills in a darkened environment. The need and use of dive light, and the potential need to resolve a problem in near total darkness, often adds greater complexity to underwater emergency management and requires additional practice to master.

Handling a night diving emergency on the surface can be nearly as difficult as in the water. Hillary Viders is an international expert in emergency dive accident management who teaches Emergency Oxygen Administration and Dive Accident Management programs for the scuba, rescue and law enforcement industries. “When I teach professional rescuers,” explains Viders, “I conduct a timed drill in which each team of four people has to assemble a complete oxygen kit from a pile of assorted components while administering CPR on an ‘unconscious’ victim. Usually a professional team (one that handles oxygen equipment and performs these tasks several times every day) can complete the drill in under 60 seconds. However, when I ask the same team to repeat the identical drill in a completely darkened room, it usually takes the best group at least five times longer, and some teams cannot do it correctly at all!”

Viders’ experience underscores the need for thorough training and preparation in all aspects of night diving. Not only must in-water skills be practiced in the dark, but skills required to effectively manage a diving emergency must also be practiced under cover of darkness.

Good physical conditioning reduces the effort required to complete a dive, thus reducing the psychological stress. A high degree of fitness also allows us to perform better and for sustained periods when problems arise and during an emergency.

The Bottom Line

There’s nothing like taking that stroll down through the reef-city at night. But just like taking an evening stroll through our land-based cities, we need to be wary and take the necessary precautions. With thorough training and preparation, we can overcome most of the human factors problems and safely enter a spectacular underwater world almost beyond imagination. “It’s magic,” says Don. “Just magic.”

The Effects of Alcohol on Divers

All divers should know that diving and alcohol simply don’t mix. Consumption of alcohol has the following effects on divers.

1. Alcohol adversely affects the central nervous system. Studies have shown that as little as 1 ounce of liquor, one bottle of beer or 4 ounces of wine can degrade motor skills and impair judgment, and will be evident in the breath and blood for a period of at least three hours. There is evidence that alcohol also impairs sleep, leaving us less rested after a night’s sleep. Fatigue reduces mental alertness and decision-making ability long after the direct effects of alcohol subside.

2. Alcohol alters the diver’s circulation. Alcohol tends to increase circulation to the surface of the skin while reducing circulation to the tissues. The result is an increase in heat loss, as well as an increased predisposition to DCS.

3. Alcohol is a diuretic and tends to dehydrate a diver. Dehydration reduces the blood’s capacity to off-gas nitrogen, since blood flow is reduced throughout the tissues, thus increasing the risk of DCS.

4. Alcohol alters the blood chemistry, which may increase the growth of microbubbles, thus leading to DCS. Researchers also have found that drinking increases oxygen consumption in the heart and other muscles during periods of exercise, so drinking may actually increase air consumption.

Avoiding Vertigo and Disorientation at Night

Vertigo is a condition in which a diver perceives motion but is unable to determine the direction or speed of movement. Vertigo can cause disorientation, dizziness and even nausea. A number of factors can induce vertigo in a diver. Cold water entering the external ear canal can induce a condition of imbalance leading to vertigo. The condition may last until the diver’s body has warmed the water. Pressure imbalances between the left and right ear during descent can also cause vertigo. Disorientation and vertigo can occur at night, when a diver has no visual references to determine orientation or motion.

Divers can often overcome the effects of disorientation and vertigo by following standard procedures at the onset of the condition. As with all problems and potential emergencies that arise underwater, divers must remember to stop, breathe, think, then act. When disorientation occurs, refer to your compass and depth gauge to reorient yourself. Holding onto one’s self or buddy until the vertigo passes can also be helpful. Remember, too, that bubbles go up. Shine your dive light to illuminate your bubbles as an additional reference. If you can’t see your bubbles, put your hand near your regulator exhaust and feel their direction of movement.

Effects of Low Body Core Temperature/Hypothermia

98.6˚F (37˚C)
Normal temperature

95 – 98.6˚F (35 – 37˚C)
Sensation of cold, increased heart rate, shivering, vasoconstriction, slight incoordination in hand movements, urge to urinate.

90 – 95˚F (32.2 – 35˚C)
Increased muscular incoordination, slurred speech, decreased or loss of shivering, weakness, apathy, drowsiness, confusion, impairment of rational thought.

85 – 90˚F (29.4 – 32.2˚C)
Loss of shivering, confusion progressing to coma, inability to follow commands, inappropriate behavior, loss of vision, temporary amnesia may occur, cardiac irregularities may develop.

Night Diving Planning and Precautions

Night diving isn’t unduly complicated, but it does require a modicum of training beyond basic open-water diving. Before attempting a night dive, be certain to receive the proper training. The following planning tips and precautions can help make your night diving safer and more enjoyable.

1. Always evaluate a dive site in daylight before attempting a night dive. The evaluation should include, but not be limited to: safe entry and exit locations, potential hazards (including entanglements), currents, navigation features and forecast weather conditions. Familiarity with the dive site reduces the psychological stress of a night dive, allowing divers to better focus on other safety concerns throughout the dive. Consider planning a dusk-to-night dive; enter the water while there’s still some light out, and you can gradually adjust to increasing darkness underwater.

2. Avoid night diving in conditions of foul weather (including forecast fog or heavy rain), high seas, strong surf, strong currents or unreasonable entanglement hazards. Such conditions pose an unnecessary risk to diver safety. Also, avoid overhead environments, including kelp, at night until you accumulate the requisite experience to do so safely.

3. Enjoy a good meal prior to a night dive, but avoid consumption of alcohol.

4. Don’t dive unless you’re well-rested and warm. If necessary, limit your daytime diving in order to be better prepared for a night diving excursion. An afternoon nap, even if it’s only 15 to 20 minutes long, may leave you feeling more rested and improve your alertness for a night dive. Mild exercise can help restore the heat deficit from daytime diving.

5. Proper site preparation is key to all night dives. Surface navigation lights, working lights, emergency first aid equipment, communication equipment and rescue gear should all be properly set up prior to entering the water. Always have at least one person remaining at the surface or on the boat to deal with problems such as failed surface navigation lights and dragging anchors. This individual should also be prepared to deal with emergencies and call for assistance if necessary.

6. Always begin a night dive with at least two dive lights per diver. If a dive light fails, the dive can be safely completed and terminated with the extra light. For hands-free night diving, consider using a wrist-mounted or head-mounted dive light as a primary dive light.

7. While night diving emergencies are part of every night dive plan, few divers actually practice emergency procedures at night. To keep your skills sharp, confidence high and stress reduced, practice night diving emergency skills regularly. Many skills can be accomplished in a pool, and others can be practiced safely in open water. If you haven’t practiced night emergency skills in the open water lately, have an instructor guide you through the proper exercises.

What is Decompression Diving?, Deco Diving Tips | Scuba Diving

Howard Ratsch — Fri, 22 Jul 2022 21:52:47 GMT

Educational Blog

What is Decompression Diving?, Deco Diving Tips | Scuba Diving

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

What is Decompression Diving?

Here's what you need to know about deco dives.

By Karl Shreeves September 2, 2021

Decompression diving is when a diver is required to make one or more stops during their ascent to give their body time to safely release the nitrogen (or other gas, such as helium) that dissolved into their tissues during the dive.

The pressure you’re under as you descend through water causes nitrogen to dissolve into your body tissues. The deeper the dive, the more quickly gas dissolves into your tissues. When you ascend, nitrogen dissolves from your tissues into your lungs and leaves the body through normal breathing. This is known as offgassing. If the amount of dissolved gas is within certain limits, you can ascend to the surface without any required stops – though a safety stop is standard recommended practice. This is called "no stop" or "no decompression" diving. Standard recreational diving is always planned as no stop diving, but you make a safety stop — hanging out at 15 feet for 3 to 5 minutes — as a conservative practice to further reduce risk.

Want to do decompression diving? Start your adventure today with PADI's Tec 40 or Tec 40 Closed Circuit Rebreather courses!

If you exceed the no stop time limits given by your dive computer, you move into "decompression dive" territory. This means you can't swim directly to the surface without unreasonable risk of getting the bends. You now have to instead ascend in stages, making progressively shallower and longer stops to give dissolved gas time to leave your tissues.

In recreational diving, a dive with a required decompression stop is considered an emergency situation caused by accidentally exceeding a no stop limit, or being forced to do so by circumstances (which should be very rare). In commercial, tec, scientific and military diving, however, dives with required decompression may be planned. This type of diving requires additional training and specialized gear.

Decompression Diving FAQs:

What is deco diving used for?
Decompression diving is appropriate when there's no other way to reasonably accomplish the dive. This is most commonly due to depth because no stop time limits become very short below 100 feet. Shallow dives can require a decompression when they are long, however. A two-hour cave exploration dive may not exceed 60 to 100 feet, but the dive is well beyond the no stop limits. Commercial divers may also make a shallow decompression dive simply because logistically it is more time and cost effective to do a single deco dive to carry out a task than to make multiple no stop dives.

How deep can you dive without decompression?
Practically speaking, you can make no stop dives to 130 feet. While you can, in theory, go deeper than that and stay within no stop limits, the no stop times are so short that "well within" limits is essentially impossible.

Are diving decompression tables the same as recreational dive tables?
Decompression dive tables differ from recreational dive tables because they list times, depths, durations and required stops well beyond the exposures recreational divers experience. While commercial and military divers often use tables, tec divers primarily use dive computers for planning and executing decompression dives.

How do you calculate decompression stops when planning a decompression dive?

Depending upon the depth, duration and equipment used, planning a decompression dive may take only a bit longer than a recreational dive, or may take hours over several days as the team considers and investigates alternatives and options.

In tec diving and much scientific diving, planning decompression dives is typically done using software and/or a dive computer. Decompression dives typically involve different mixes of breathing gases, which are selected based on the dive depth and duration. To best consider all these variables, today computers are used to determine and plan the best gases and the dive schedule, plus emergency alternatives to handle reasonably possible problem situations.

Trimix (helium/nitrogen/oxygen) is used on deeper dives to reduce gas narcosis to acceptable levels. Enriched air nitrox and pure oxygen are used during decompression because they accelerate how fast dissolved gas leaves the body. The diver switches between these during ascent, or, when using a closed circuit rebreather, changes the gas ratios during ascent. Each gas mix has a limit on how deep and how shallow it can be breathed safely, and decompression time increases disproportionately with depth, so that for dives deeper than 200 feet, often decompression is longer than the time spent at depth. The dive plan must therefore include how much of each gas is needed, where and when it's used, backup gas and equipment for emergencies, and how much of all this the diver can reasonably manage.

What happens if you don’t decompress when scuba diving?

If you exceed a no stop limit and surface without making the required stop or stops, your risk of decompression sickness is considered unacceptably high. How high? It depends. Any dive has some risk of decompression sickness because people vary in their physiologies and susceptibility. No computer or table can guarantee decompression sickness will never occur, even within its limits.

What’s a good deco dive computer?
Choose a dive computer intended for technical decompression diving. It should be capable of using several different gas mixes on the same dive. Fortunately, these are not difficult to find – ask you PADI Instructor and PADI Dive Center or Resort for guidance.

An important point is that you need not one, but two compatible dive computers for this type of diving. While dive computers are highly reliable, you would not want to be stuck without your decompression info if there were a malfunction, so standard practice is to dive with two, staying within the limits of the most conservative (even identical computers will vary slightly throughout a dive).

What should I do if my dive computer says “deco,” but I didn’t mean to do a decompression dive? What should I do if I miss the stop?
Assuming this happens by accident on a no stop recreational dive, ascend to 15 feet (or deeper if specified by your computer) and stay there until it "clears," meaning you have stayed the required stop time. Most computers show you the time as it counts down. For a recreational "oops" situation, the time would typically be short with only one stop required. However, you may be low on gas, so do not run out of gas underwater. Stay as long as you can, but if you don't have enough air to do the stop (or you miss it altogether), surface with enough air to ascend at a proper rate and exit the water. Then stay calm, alert the divemaster and your buddy, breathe oxygen if available and monitor yourself for DCS signs and symptoms. Do not dive for at least 24 hours or as specified by your computer. If you have or suspect DCS, contact the Divers Alert Network and emergency medical care.

How can I learn decompression diving?
You can start into tec diving with either PADI’s Tec 40 course (open-circuit tec diving) or the PADI Tec 40 Closed Circuit Rebreather Diver course. These courses begin the transition from recreational diving to technical diving, which includes planning and making tec dives. After completing these, you continue into the Tec 45, Tec 50, and Tec 65 courses, in which train you to make deeper, multi-stop decompression dives.

How You Can Prevent Diving Emergencies

Howard Ratsch — Thu, 23 Jun 2022 13:12:21 GMT

How You Can Prevent Diving Emergencies | Scuba Diving

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

How You Can Prevent Diving Emergencies

Preparation can prevent problems large and small.

By Annie Crawley November 19, 2020

Don't take basic equipment like masks for granted – it can make or break a dive.

Even with nearly 10,000 dives, I’ve only had my mask or regulator kicked off twice—both times by students—but I’ve had to clear my mask on every single dive. (If you see fins coming too close to your face, get your arms into action and push those fins away!)

Twice I’ve had to deliver an alternate air source to a buddy, both during a safety stop. I prevent out-of-air emergencies by checking my own air supply—and my buddies’—multiple times on every dive. I’m vigilant about preventing incidents from occurring, and value continuing education for all divers. Nothing can ruin that trip of a lifetime like not being properly trained or prepared for the adventure you seek.

Recently, I taught a weeklong Rescue Diver program. The skills students learn in this class—and what dive professionals gain teaching it—will change your diving life forever. I recommend all my students become rescue divers, and also recommend they invest in dependable dive gear from their local retail dive center.

Breaking down important considerations and protocols will help you “dive like a pro” and recognize and prevent in-water emergencies.

1. Consider the ABCs of diving: airway, breathing and clearing, on every dive. Even the most experienced divers can have an issue if their eyes, ears, nose or mouth unexpectedly come into contact with water. At the surface, make sure you inflate your BC and are positively buoyant. Have your snorkel or regulator in at all times, to keep your airway clear. When changing between them, dip your face in the water to avoid swallowing water from a passing swell. I know many divers skip the snorkel in pool-like conditions, but wind and weather can change during a dive, turning that “pool” into a washing machine with 3-foot waves. I’m always kitted with a snorkel, on every dive, in case of changing conditions.

2. Never force your ears to equalize. If you are prone to congestion, check with your doctor. Find a decongestant that works for you. You can get snotty on any dive; knowing how to blow your nose into your mask is an art form. Sometimes when you have difficulty equalizing, you have one stubborn piece of snot in your ear canal. You are stronger than your ears and can hurt them if you push too hard—always relieve pressure by ascending to a shallower depth or to the surface to blow your nose.

3. A comfortable, properly fitted mask is the No. 1 piece of personal equipment a diver carries. If you or your buddy struggles with mask issues on a dive, it can ruin the dive. There’s nothing worse than a foggy mask—except a night dive with a foggy mask. After you rinse the defog from your mask and seat it on your face, don’t break the seal; if you do, you will need to re-defog your mask.

During your dive, if you smile, adjust your reg or your mask strap moves on the back of your head, your mask may leak. Clear your mask. If it fills with water again, usually your mask strap is too high or low on the back of your head, or too tight or too loose. The mask could be riding up, giving you a rabbit nose, or falling down over your lips—either way, it breaks the seal and causes a leak. It’s physics.

Exhale through your nose and move your mask around on your face to seat your mask properly. Adjust your mask strap and check again. A leaky mask can lead to congestion and equalization issues. If you get water in your mask, you can inhale the water, leading to issues with airway control.

4. Create a routine for every time you dive. Set up your equipment the same way every dive.

Together with your buddy, do a precheck on your equipment. Remember BWRAF: Begin With Review And Friend, Big White Rabbits Are Fluffy, Beer Wine Rum And Fun—no matter the acronym you choose to use, be sure to check all points and talk about your dive plan before getting into the water.

· BCD: Make sure it is on properly and you know how to operate it.

· Weights: Do you have the correct amount, and do you know how to release yours or your buddy’s if needed?

· Releases: Check all releases including tank release.

· Air: Do you have a full tank? How do you communicate air issues?

· Final check: Discuss your dive. I teach this “pre-check” before getting into our exposure suits; our “buddy check” before we get in the water goes quickly because any issues were spotted in our pre-check.

5. Inspect your mask straps, fins, compass, dive knife, gear collecting bag. Have you bitten through the mouthpiece on your regulator? If you are wearing a hood, have you adjusted your strap to compensate so it is not too tight on your face? Carry a dive slate and dive light with you on every dive. If you are renting gear, does the needle on your air gauge read zero when the air is off, or is it permanently stuck at 500? How did you learn to show air?

I recommend showing how much air you use with your buddy every 500 psi/40 bar. That way, both buddies are aware of how to adjust their dive plan throughout the dive so they will never run out of air, while maximizing their dive plan and time underwater. Review hand signals.

Remember to ask for help not because you are weak, but because you want to become a stronger diver.

When you are a scuba diver returning to the water after a break:

Howard Ratsch — Mon, 23 May 2022 13:18:37 GMT

Educational Blog

Returning To The Water After A Break | Scuba Diver Mag

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

When you are a scuba diver returning to the water after a break:

by Adrain Stacey

You’ve not been diving in what feels like years and you’ve just realised that you’ve put the BCD onto the cylinder backwards! You quickly turn it around and hope no one saw. Now, which way the regulators and gauges go again? This regulator looks different to the one you had last time – “am I doing this right?” – You feel stupid asking, but it is probably better to check after all. You smile enthusiastically, nervously wondering if you can still remember how to dive.

Okay! You’ve got your kit all set up and it’s time to walk out to the dive site. You are excited but there is this wobbly feeling, everything just feels a bit weird. As you get into the water you realise that you are fumbling to find the inflate button. Finally, it’s time to descend, “where’s that regulator?” you remember to sweep behind you and eventually find it, but you worry that everyone is sick of waiting for you. You hit the deflate … and you are still on the surface! Your buddy and the guide look up at you patiently as you gradually make your way down towards them.

This used to be easy, but now it feels odd and strangely vulnerable.

But, as you start to swim along, things start to fall into place. Each time you reach for your inflator hose you find it faster. The second time you clear your mask you remember to focus on breathing through your mouth (the first time resulting in some spluttering). By the end of the dive you are really starting to enjoy yourself again and the nerves have melted away. After a few more dives it’s all coming back again.

Does this sound familiar? Look at all the things we need to know and do when we dive, from putting our equipment together, carrying out checks, finding clips to fasten and buttons to press … These are motor skills that took time and effort to learn. The ability to perform these skills got laid down in pathways of nerves that run from your brain to your fingers and toes; and all the way back again. When we have a break from diving, these pathways are unused.

Like tracks in a field the grass grows over them and it can be hard to find our way through when we return. But the pathways are there! By re-using the skills: we open them up again. Repetition and practice sends signals down the nerves and the connections strengthen again, which is why we get better and faster at the skills the more we do them.

There are many pathways you will need to revisit when you return for your first dive after a long break. There will be connections that must be made just to get into the water, for example being able to locate and press the deflate button. (You won’t go very far if you can’t do that!) You should also practice some basic skills that you need for the dive, like clearing your mask in case it fogs. Plus, getting the hang of buoyancy will be important.

But what about the hidden pathways?

There are things you would need to do if something went wrong. For example, practicing sharing air in case of loss of gas, or dropping your weight belt in case of failure to establish buoyancy on the surface. When was the last time you went down those tracks? If you needed to, would there be a clear route through, or would you be struggling to hack your way through the overgrowth in an emergency?

In the same way that tracks fade when they are not followed regularly, our skills atrophy when we do not practice. Look back through your training, are there any skills that you have not used? Often the most important skills are the ones we may never need to do for real, so we forget about them … or tell ourselves we know how to do them. But if those skills have not been practiced, they will not be accessible. Why not take a wander down those overlooked pathways by refreshing skills and practicing scenarios with your instructor. Regularly re-discovering what you can do is all part of your diving journey.

It’s a good idea for divers who haven’t been in the water for a significant period and are thinking about returning to enroll in a scuba refresher. There is also an offline, tablet-based program called ReActivate which covers all the knowledge you learned during your Open Water Diver course and allows you to refresh your knowledge after being out of the water for a while. The program should get you back to feeling comfortable in the underwater world in less than a day. Check it out and get ready to start diving again.

Blood in your mask after a dive is concerning, but not necessarily dangerous.

Howard Ratsch — Sat, 23 Apr 2022 10:58:07 GMT

Educational Blog

Don't Force It | Lesson for Life | Scuba Diving

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Blood in your mask after a dive is concerning, but not necessarily dangerous.

Steven P. Hughes

Tina was on day three of a four-day dive trip. Conditions were great throughout the trip, with bright sun and warm water. On the first two days, she made three dives each—two from a boat in the morning and then a third shore dive each afternoon. As she finished up her second dive on the third day, she thought about skipping the shore dive that afternoon and taking a shopping excursion to buy some presents for friends at home.

When she got to the surface and pulled off her mask, she was shocked to see the nose pocket full of blood. She immediately grew concerned.

The Diver

Tina, 40, had been diving for five years. Every year she made two trips to the ocean, making between eight and 10 dives each trip. She had an Advanced Open Water Diver cert and was nearing 100 lifetime dives.

The Accident

As Tina descended for that dive, she noticed it was a little harder than usual to equalize her ears. She blew extra hard to equalize and had to pause twice to let her ears “catch up” with her descent.

She was shocked at the amount of blood in her mask when she reached the surface. She immediately consulted a diving physician when she reached shore, worried that something was seriously wrong with her sinuses or ears.

Tina told the doctor she had been feeling a little stuffy that morning when she woke up but had written it off to the air conditioning unit in her hotel room. She didn’t have any significant medical history with her sinuses.

Analysis

Blood in your dive mask at the end of a dive is most likely not a life-threatening situation, but it is something just about every diver will have to deal with at one time or another over their diving career.

Every diver learns basic ear equalization techniques during their initial dive training. Some divers are lucky and have ears that equalize easily. Other divers have to work at it.

The ears and the sinuses are sensitive to pressure changes and must be equalized to the water pressure every few feet of descent. Most divers learn to pinch their nose and blow gently until they feel their ears “pop.” Many divers learn to pre-equalize their ears, overinflating them before they begin to submerge to get ahead of the pressure.

Problems begin when there is even the slightest blockage in the Eustachian tube, often described as a soda straw leading from your mouth to your middle ears. Any kink or restriction in that straw makes middle-ear equalization harder. To overcome that problem, divers sometimes pinch their nose tighter and blow harder, even though they are taught not to do this. And that’s where the problems begin. In Tina’s case, it caused a blood vessel in her sinuses to rupture. The technical term for this is epistaxis, but in other words, she gave herself a nosebleed.

Nosebleeds are common for both freedivers and scuba divers. The linings of the sinuses are filled with capillaries and blood vessels. When one of them breaks, or leaks, it releases what appears to be a large amount of blood. This can look even more troubling when it collects in the nose pocket of your mask and mixes with a little water. A single short-term nosebleed generally isn’t something to be concerned about, as long as the bleeding stops on its own. Bleeding that does not immediate stop, or that occurs repeatedly, requires medical evaluation.

Often divers have a full feeling in their ears after a diving nosebleed, but that is likely related to the underlying cause of difficulty equalizing the ears. When you don’t equalize your ears promptly, the mucosal tissue in your sinuses can actually leak blood into your middle ears to equalize the pressure itself. This blood stays in the middle ear though, and doesn’t drain from the mouth or nose. That can cause its own set of problems, including middle ear infections.

Equalizing

If you have a temporary blockage from a cold, or a more serious issue like an obstruction of some sort, you should wait until the condition clears or discuss the situation with your doctor before returning to diving.

But if you have what many divers refer to as “slow ears,” there are several techniques you can use to help your ears equalize faster. Simply pinching and blowing harder is not a solution, and can cause serious ear injuries. This is why you’re taught to equalize gently. As mentioned earlier, you can gently equalize your ears before you begin your descent, giving them a head start. Other techniques include jutting your jaw forward or moving it from side to side as you equalize. If one ear is slower than the other, stretch your neck while you equalize, pointing the slow ear upward and keeping your head above your feet on descent. This helps straighten your Eustachian tube.

With some practice, these add-on techniques will become second nature. If they do not, and you still struggle with ear equalization or have repeated nosebleeds when you dive, you should consult a physician, preferably one with experience dealing with scuba and freediving.

A side note on sinus medications: Some divers regularly take them when diving. This is risky. If you take a sinus medication for more than three or four days in a row, it can cause significant rebound effects once the decongestant wears off. Known as rebound rhinitis, your symptoms may actually become worse in a few hours when the medication wears off, which can be especially problematic if it wears off while you are underwater and still have to surface with a blockage. It’s best not to use medications to dive.

BOAT DIVING ETIQUETTE

Howard Ratsch — Thu, 24 Mar 2022 14:19:04 GMT

Educational Blog

Boat Diving Etiquette - SDI | TDI | ERDI | PFI (tdisdi.com)

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

BOAT DIVING ETIQUETTE

By Jay King

I learned to dive many years ago (before dirt I think). My instructor at the time, Scott, insisted on our final two checkout dives being off of a boat in the ocean – because this was Wrightsville Beach, NC. North Carolina wreck diving was my goal and he wanted me to be prepared for it, so I was lectured on boat diving etiquette before I ever set foot on a dive boat.

Over the years, I’ve progressed in my diving (Hypoxic Trimix, CCR) and in my preferences of boats. Most of my diving now is on 6-packs (maximum of 6 divers) with other divers at or near my experience level. Recently, I’ve been on a few dives on some larger boats (12-18 divers) with a mixture of divers, some who are just beginning their adventures to others that are more advanced. Many of these divers are only now trying out NC wreck diving. One thing that is obvious is that many of them did not get the introduction to boat diving etiquette that I did. I thought I’d sit down today and share some of the knowledge that I’ve picked up over the years.

Communicate with the dive center or charter company

First and foremost is: call/message/email and ask questions. Whatever your question is, just reach out to the shop or charter company. Want to know if your rental gear will be on the boat or if you have to pick it up yourself? Call. You don’t want to be underway and find out your rental tanks aren’t on the boat and are still at the shop waiting for you to pick them up. Want to know if the boat will be providing a 3-course meal? Call. You don’t want to be out on the water for 8+ hours with nothing to eat between dives. You’ll see this mantra throughout. Why? Because boats operating in the Caribbean, for example, will be very different from a 6-pack running out of Hatteras, NC.

Planning

Next, planning for a boat trip. What gear should you bring? Diving from a boat isn’t like going to a local lake, river, spring, or quarry where you’re only limited by the amount of gear your vehicle can haul. Space on a boat is limited and you should only bring what you need for the dive you’re doing. Think hard about what you bring. Do you really need that scooter if you’re diving a small in-shore tug? Do you need that lionfish gear if you’re diving shallow spots that don’t normally have lionfish? Do you need to bring that briefcase sized hard case with your laptop for a half-day trip, or could you wait and edit your videos and pictures on shore? Do you need to bring a bag of spare regs, parts, and hoses along with your super-sized toolbox? For a dive boat, most people normally have one dive bag worth of gear and a dry bag that will fit under the bench. Some boats have specific space for cameras and specific storage spots for deco/bailout bottles. Call ahead of time and find out.

If you aren’t familiar with the wrecks or reefs you’re going to be diving, which might influence what gear you want to bring, just call and ask. All good charter operators will have emergency gear on board and most of them will have a well-stocked toolbox and spare gear. The bottom line is that there is no need to bring gear that the boat has or that you won’t use/need. You need to find out how much space there is on the boat as well as what equipment the boat has on board.

Don’t forget to ask about food and water! If you’re used to diving boats in the Caribbean, then this may be a foreign concept. Most charters on the US East Coast will provide water and nothing more. You need to find out what they do provide and plan accordingly. Water, snacks, and something even more substantial if it’s a full-day charter.

Lastly, make sure to know what time to be at the dock and if there are parking restrictions, then be there on time. Is 7:30 am the time to be at the dock, or is it when the boat plans on leaving? Don’t be the person that shows up late and holds up the boat and don’t be the person who gets back to the dock to discover their car has been towed.

On the boat…

Once you’re on the boat, get your gear set up. In many vacation destinations with “valet” diving, someone else may be carrying your gear to the boat and setting it up. From my experience, every dive operator I’ve ever used from West Palm Beach to Cape Hatterasexpects you to carry your own gear on board and set it up yourself. Often these boats will be passing through rough inlets and into an ocean that is a bit “bouncy”. Trying to get a BC on a tank is no fun on a rolling boat – get it all done before you leave the dock and stow everything out of the way.

How I like to unpack on a boat

My personal preference is to unpack:

My wetsuit, fins, etc.
Put my gear bag under the bench
Stack gear on top of it in the opposite order that I will need it.
- So, bottom to top we have:
- - Empty gear bag, fins (with boots in the foot pockets)
  - Pocket shorts
  - Wetsuit

Something to note

There is a key phrase here that some of you may have missed. That phrase was “under the bench”. I have recently seen several divers using large, semi-hard sided bags that are so big they would be checked luggage at the airport. If your gear bag or bin can’t fit under the bench where your gear is, then it shouldn’t be on the boat. Huge gear bags, or lots of bags that won’t fit under the bench, take up valuable space on an already crowded boat. Other people won’t be as careful with your gear as you are, so leaving it in the way is asking for trouble.

WHERE DO YOU STORE THINGS THAT NEED TO STAY DRY?

Next, where is the other stuff you’ve brought going to go? I often bring spare batteries (for lights, dive computers, and the CCR) that the boats don’t have. I also might bring a towel and maybe some dry clothes to change into. These items need to go somewhere dry and out of everyone’s way. Just ask the crew where the best spot is.

Stow and secure

Finally, before the boat gets underway, make sure that all of your gear is stowed and secure. Make sure that tanks are bungeed in so that they don’t fall, for example. Many of the dives I do are technical, so I bring decompression or bail out tanks – boats will normally have specific spots for these that will keep them safe. As the saying goes, if your tank falls and breaks someone else’s mask, they are still going diving, but you may not be.

Underway and Diving

I think the main thing to know at this point is to listen to crew instructions. Especially listen to the boat safety briefing – there may be rules about staying seated when going through an inlet or in rough seas, and I’m sure that there will be important information about the head and the best “fish feeding” spots.

Once you’re at or very close to the dive spot, begin gearing up, but stay out of the way of the crew. The crew needs to get the boat tied in and prepped for your dive. Typically, once the boat is tied in and prepped, the captain or one of the crew will give a site briefing and discuss any specific procedures. For example, what to do if you can’t find the anchor at the end of your dive – listen to them!

One procedure that I see ignored far too often off the NC coast is to not hang around at the surface. Often, we have current, and hanging around on the surface, especially not paying attention to the tag line trailing behind the boat, can get you into trouble quickly. Work with gear on the boat or under the water is what most captains will say. You do not want to ruin a dive by jumping in and floating away because you were too busy fixing how a piece of gear is attached.

Be aware of time

Although no captain or crew is going to rush you into the water before you’re ready, be cognizant of time. Half-day charters in particular may be on a schedule. Even a full-day charter may be trying to get back before dark or before dead low tide at the inlet. Problems can certainly hold you up, but if everyone else is off the boat 5 minutes before you’re even thinking about standing up, then the crew is starting to wonder if you’re mentally ready for the dive (typically divers who gear up slowly are nervous about the dive). At a minimum, the captain is starting to think about the difference in surface intervals between you and the other divers.

If you know that you are slow at gearing up, start gearing up sooner. When I switched from OC to CCR and had to do a pre-breathe, I adjusted when I started gearing up so that I could still get in the water quickly.

Heading in

Heading Home is the easy part. Personally, I try to get all of my gear packed up and stowed while the crew is getting the boat ready to leave the dive site, but as long as your gear is stowed and out of the way, most operators don’t mind if you wait to pack your gear bag back at the dock.

Tip your mates

Once you are back at the dock, get your gear off of the boat as quickly as possible. The crew has to clean the boat at a minimum and may need to prep it for another charter. And don’t forget to tip the mates! Every charter I’ve ever been on mentions this. I’ve heard some people say $10/tank but I personally opt for something closer to 20% of the charter cost. Tipping is a personal choice and may only be expected in the US and Caribbean. Just be prepared.

A note on cancellations

One final thought is that you should always read the charter policy on refunds. Reputable charters will refund your money if they cancel for some reason (e.g. weather or mechanical issues). Most charters will also have a policy about what happens if you cancel. That policy typically means that if you cancel within some time frame (1 week, 2 days, etc.) then you still have to pay for the spot if it can’t be filled. If an individual, or a dive shop, is responsible for the charter and you cancel on them at the last minute, then the individual or shop may have to pay for the spot even if it can’t be filled – don’t be the guy that doesn’t cover your spot after canceling because you may not be invited back.

DIVER TEST: Nautilus LifeLine GPS Personal Locator Beacon - Divernet

Howard Ratsch — Tue, 22 Feb 2022 14:56:03 GMT

Educational Blog

DIVER TEST: Nautilus LifeLine GPS Personal Locator Beacon - Divernet

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

TAKE EIGHT DIVERS AND SUBTRACT TWO. You’re left with six, right?

And that’s the simple arithmetic that the crew of a luxury-resort speedboat couldn’t manage. They returned to shore with only six people.

Across the table at a London pizza-house, I sat interviewing Olga and Robert, the pair abandoned off the coast of Cuba.

That they had survived was down to luck. A fisherman had spotted them bobbing in the water three hours after they’d surfaced.

In the packed restaurant, there were no raised voices complaining about wrong dishes from any of the busy tables surrounding us, because the waiters had logged the orders. Olga and Robert were not logged out of or into their boat, and were not missed.

The first the dive-centre knew of their clients’ near-fatal ordeal was when the couple walked in and told them.

My resulting feature, Missing, was published in 2003. It reviewed a handful of incidents in which divers and boats became separated. I’d worked on the story for two years. That the article was so delayed was partly down to a long-gone Florida dive-operator refusing to discuss how it also forgot two of its customers, who spent 24 hours on a light-tower before being spotted by a yacht.

A lawsuit followed and sentencing required the operator to share advice on how to avoid a repeat with anyone interested. I thought diver readers would be very interested, but the company wasn’t sharing, so my report stalled.

Exasperated, and with the imminent release of Open Water (the fictionalised film inspired by two divers left behind and never found off Australia in 1999) the Editor pushed me to finish the piece.

He also pointed out the topicality of a dozen divers going missing from their liveaboard in the Red Sea just as the movie was hitting the cinemas. The truth is, however, that when it came to such incidents, I was spoilt for choice.

And, all these years later, I still would be.

Causes of Separation

Divers get separated from boats for many reasons. They don’t always follow briefings, and surface in the wrong place, or get caught in unexpected current and swept away.

A skipper makes a mistake, or the boat breaks down. If the boat has a proper accounting system, the crew know that they have divers missing and should get searching quickly, but this isn’t always the case.

In some incidents, boat-crew had no radio to summon help. In others, they delayed reporting the incident for hours, hoping to find the divers themselves. In that time a diver can drift for miles, and night can fall. A diver’s head is a tiny target, even under ideal sea conditions (“you’re looking for a cabbage”, a sailing instructor told me).

Flags, DSMBs and signal mirrors can help searchers; an air siren might be heard at short distances over quiet engines. But luck plays a scarily big part in being found. The worst scenario, as with Robert and Olga, is not to be missed at all and have no-one looking for you.

The Product

The Nautilus LifeLine is one of the most important safety aids ever made for divers. It’s a personal location beacon (PLB), a radio transmitter that can signal for help and reveal your exact position to a searching boat or aircraft. It empowers you to do something positive towards surviving a separation.

PLBs are not new, and the LifeLine itself has been around for some years, but the version I tested is a new model although, as I’ll explain, it isn’t necessarily an upgrade.

It was developed by Mike Lever, owner of well-known liveaboard Nautilus Explorer, following a scare. “The Nautilus LifeLine was the culmination of spending 20 years in dive skiffs in the chilly, current-swept waters of British Columbia and Alaska,” he explains. “Wondering. Hoping that all my divers were going to surface where I expected them to.

“I always worried about losing a diver and then one day, off Wooden Island in the Gulf of Alaska, one of my divers didn’t surface when they should have. We started searching. The current was increasing as we got further from slack. I tracked out into the open gulf in a 6-8ft swell with no joy.

“I called the US Coast Guard for help and they told me that it wasn’t an emergency yet (in other words, piss off and don’t bug us until it’s too late). It took us 50 minutes to find the diver drifting several miles from shore.

“We were all in tears – except for the missing diver. He was calm and fine, because he had seen us searching for him and assumed that we would find him.”

I have helmed small boats but have no formal boat-handling training. I see boats as either taxis or wrecks so, to help test the LifeLine, I turned to Nick Balban, a diver of some 25 years experience, BSAC instructor and former Gibraltar SAC Diving Officer. He is professionally qualified to skipper vessels of up to 24m.

The Design

The LifeLine’s electronics are integrated into a compact polycarbonate housing that’s watertight to 130m. A single catch, easily operated with a gloved hand, lets you open the O-ring-sealed lid on the surface.

This exposes the aerial and three push-button controls. These parts are waterproof, but not pressure-resistant. Two Philips-head screws give you access to the battery chamber, which takes two CR123 cells.

The LifeLine is not an electronic positioning indicating radio beacon. EPIRBs work over much longer distances, by relaying their signal via a satellite, alerting call-centres that can co-ordinate a rescue. Standard safety equipment for operating far from land, they are found on aircraft and yachts because they can summon help anywhere in the world, even though that help might take days to arrive.

The LifeLine transmits a radio signal limited by both its power and antennae, and has a claimed range of 34 miles. In many diving locations, the closest and fastest responder is likely to be your own or another dive-boat, given the lack of search and rescue infrastructure and time needed to deploy the device in many destinations. So the range should suffice.

Once you’ve flipped open the lid, removing a slip-off safety guard allows the aerial to automatically uncoil (watch that it doesn’t flick into your eyes) and reveals the red emergency push-button control. Hold this in for five seconds to send out a distress signal.

It attempts to contact suitably equipped craft within range and, if it succeeds, your GPS co-ordinates will be displayed on their navigation instruments.

There’s a 20-second window between pressing the call button and the unit transmitting its emergency signal, during which time you can turn the unit off in case of accidental operation.

Along with the distress button, two other buttons control the LifeLine. These can be accessed without removing the cover, which is basically a safety lock and should, along with the five-second press, prevent misfires.

One is the on/off button, the other a test button, used to check that the battery is functional. Waterproof user instructions are printed on the unit.

The previous LifeLine allowed you to talk to rescuers via a built-in walkie-talkie. I can see how reassuring this could be, because the current model has no way of indicating that your distress signal has been received and is being acted upon.

However, in some parts of the world a radio licence was required to use the LifeLine so, for practical reasons, it’s been dropped to remove that barrier to ownership. This is why the change in specification isn’t an upgrade, even though the electronics have been improved.

What is a major improvement is that the LifeLine now has a function that broadcasts your position, not as an emergency alarm but as an advisory measure.

The psychological benefit of this option is that it removes the conflict divers might feel if they’re concerned that they have not been seen, but are reluctant to set off a full-blown search until sure that they’ve been lost or abandoned!

For me, that’s a huge selling-point.

The LifeLine is now basically an AIS (Automatic Identification System), commonly used on ships to prevent collisions by making them visible to other sea traffic. Each AIS is specific to the vessel and you can check the ship’s name, tonnage and other details online.

Set off the LifeLine’s AIS function and your position is indicated by a numbered icon on the screen of the boat’s chart-plotter, allowing each individual LifeLine to be identified.

In theory, in advisory mode the AIS function can also be linked to your boat’s radio, so it automatically sets off an ear-splitting alarm that can be silenced only by acknowledging it.

Otherwise, the on-screen display is passive – someone has to notice it.

Again, to me, the unignorable audible alarm was a persuasive selling point, knowing how lax “cover” can be. However, for unclear reasons, legislation makes this safety feature inoperable in European and some other waters, and so it proved in Gib.

Pairing the LifeLine with your boat requires use of a free app and is straightforward.

It can be used to train on the unit or, as Nick and I did, to get a feel for how it works from the boat-crew’s perspective by checking the helm instrument read-outs.

Because the LifeLine’s capabilities depend on local regulations, and these affect how it should be programmed, it’s essential to check the manual before use, especially as a dive-traveller.

As a guest on a dive-boat, you’d need to ask the skipper to agree to pair your unit, but it’s difficult to see any reasonable objection to doing this. You should then follow the crew’s instructions regarding using the LifeLine.

Depending on where you are in the world and whether you have paired your unit with your boat, the LifeLine might first try to alert only your vessel of your location before, 30 minutes later, sending out a distress signal to all ships within range and able to receive the transmission.

This will set off an audible alarm, which should be treated as an emergency by these craft. They should immediately head for the GPS co-ordinates provided by the LifeLine.

Within those 30 minutes you can cancel the transmission if your own boat has found you.

To help rescuers locate you in the dark, a white LED flashing beacon automatically switches on as daylight fades.

The LifeLine stores easily in a BC pocket, though a dedicated pouch is also available.

This has a coiled lanyard to which to secure the LifeLine, so if you fumble and let go of the unit, you’ll still be attached to it when the cavalry rocks up.

It also allows for mounting the LifeLine high on a shoulder-strap, so it’s clear of the water and you don’t need to hold it while you await rescue.

Conclusion

Does owning a PLB guarantee your rescue? No, there are issues, not with the LifeLine itself but with use and misuse of PLBs in general, and these might affect how much attention gets paid to its alarms.

Accidentally activated PLBs and EPIRBs are floating around that have been washed into the sea or are going off on seaworthy yachts unnoticed. Another concern is that smugglers deliberately set off PLBs to lure patrol-boats away from their trafficking routes, creating false alarms and making would-be rescuers sceptical.

So, as with car alarms, a crew-member on a passing boat might glance out to see if he can see a sinking superyacht, but not start searching for a person in the water. Nick said that he would like to see a display that informs a vessel what the PLB is attached to – in our case a diver – so that look-outs know what to search for.

Even so, the unit adds a huge line of defence. We came away highly impressed with the Nautilus LifeLine, a unit that a number of dive-boats now issue to guests.

Is getting lost and found at sea a lottery?

I DON’T KNOW any big-money lottery winners, but I do know a disturbing number of divers who’ve spent a few hours adrift.

That can be all the time in the world to wish you’d bought a Nautilus Lifeline.

As Dan Orr, former president of Divers Alert Network, told me: “Even the best divers make mistakes, but the most safety-conscious divers have a Nautilus LifeLine to help keep those mistakes from turning into a tragedy.”

3 Ways To Beat Seasickness When Diving |

Howard Ratsch — Sat, 22 Jan 2022 18:22:04 GMT

Scuba Diver Editor-in-Chief Mark Evans

3 Ways To Beat Seasickness When Diving | Scuba Diver Mag

This article represents the views of the authors. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Seasickness

If there is one thing guaranteed to ruin a day, a weekend or a week of diving, it is feeling seasick. There is no magic bullet or cure-all for seasickness, but I will offer up some hints and advice gleaned from 25 plus years of dive travel to help you deal with the demon of seasickness.

There can be nothing worse than feeling seasick. I have seen far too many burly blokes reduced to dribbling wrecks on dive boats because of the effects of seasickness. I thank my lucky stars that I seem particularly resilient to seasickness, and however rough it gets, I seem to be fine. The same cannot be said for some of my boat mates over the years, and I thought collating all of the tips and tricks I had seen used in that time to combat seasickness would be very useful for anyone who is prone to this ghastly condition.

Seasickness can mean the difference between an epic day of diving and wishing someone would put you out of your misery. I distinctly remember two young students who joined us on a boat for a great white shark cage dive out of Gansbaai in South Africa. They looked a little green about the gills when they got on board, and given we were in the calm of the harbour, I didn’t think this boded well for the rest of the day. Sure enough, as we left the confines of the harbour and headed out towards Dyer Island across huge rolling swells, they curled up in fetal balls on the deck and make quiet mewling sounds.

Things only got worse for them when we reached our dive site and moored up side-on to the swell. Once the chum was being ladled into the water, and the scent of fish guts and other delights blended with the smell of thousands of cape fur seals sat on the nearby rocks, this heady aroma had them retching over the side of the boat for what seemed like hours on end. They felt so lousy they didn’t even attempt to suit up and do a cage dive, and instead alternated between barfing and wanting to die until we returned to the harbour. I swear one of them crawled on to the shore and kissed the ground. You really don’t want to be in that position.

So, how can deal with seasickness?

Firstly, don’t be afraid to turn to your friendly neighbourhood pharmacist to tackle seasickness head-on. Trying to prevent the onset of seasickness in the first place is by far the better plan of action than attempting to deal with it once you are well and truly in its throes. There are a multitude of seasickness pills available wherever you are in the world, but the most important thing you need to look at is whether it causes drowsiness. Many meds have this warning, and you do not want to be drifting off for a nap while you are on a dive, so it is vital you only use motion-sickness medicine that doesn’t cause drowsiness.

Once you have found pills suitable for use while diving, it will be a case of trial-and-error. You will probably find that certain products will work better for you than others. I have the same issue with hayfever – most of the big-name brands do not work, but a cheap-and-cheerful one-a-day pill from a local discount store sorts me right out. So try different pills across a few dive trips and whichever one comes out on top for stopping any queasy feelings, make that your go-to medicine.

Regardless of the brand of pill you opt for, make sure you give it time to work! It is no good taking it as you step on the boat, you need it to be in your system, so either take it early that morning, or if you are having a particularly early start, even pop one the night before.

My wife Penney can suffer from seasickness and routinely takes pills as a precaution – the way she sees it, better to have the assistance of proven medicine and have a great time out on the water than risk her trip being ruined. She also utilises bands which go around her wrists. These have a little plastic fitment which presses on to pressure points on the wrists and is supposed to ease motion-sickness. She leaves these on right up until it is time to kit up and get in the water, and puts them back on as soon as she is out of her wetsuit after the dive. Pills and bands might seem overkill, but she says if she can stack the odds in her favour of not feeling any effects of seasickness, she is all for it.

Where you sit on a boat makes a difference

Right, let’s move on to actually being on the boat. Where you sit can also make a big difference to how queasy you will feel out on the water. If you are on a small boat, like a RIB, obviously your seating options are limited, but I would suggest aiming for being halfway down the tubes on either side. You don’t want to be near the bow, which will be going up and down the most, and you don’t want to be right at the stern as you will be near the outboard, and fuel fumes are not the most pleasant smell at the best of times, never mind when you are feeling rough anyway.

If you are on a bigger day boat, then you have a bit more scope. I’d suggest avoiding the flybridge and the bow, and if there is a cabin of sorts, stay out of this in the fresh air. Being cooped upside where it can get hot and sticky, and there is no through-flow of air, is a sure-fire way to bring on seasickness. Stand or sit where you are in the breeze, and don’t sit with your head down or looking at the deck – try to look at the horizon.

There are even more options on a liveaboard. Again, I’d suggest trying to avoid the higher deck levels – yes, you might get a nice breeze up on that top sundeck, but you will also be more susceptible to whatever swell you are motoring into. Aim for a lower deck where you can still feel that fresh air. I\ have seen people retire to their cabins when underway and they are feeling a little nauseous, and to me, this is the worst thing you can do – be closeted away in an enclosed space.

What to do when you reach the Dive Site?

Ok, so that’s travelling on the boat, but what do you do when you reach the dive site? My business partner Ross says that the best place to be is in the water, and he is like a lemming when we are diving off a boat – as soon as the boat is anchored up and the crew have said the pool is open, he is over the side and into the water. Even just floating on the surface he feels substantially better than being sat on the deck of the boat, even though he will still be moving with any surface swell.

However, actually being underwater away from any surface conditions is the ideal place to be, so if you are prone to seasickness, don’t faff about getting ready. Make sure you are kitted up and ready to go so you can be among the first off the boat. That said, don’t be fully ready too early – sat down in full dive regalia and starting to overheat is a surefire way to start feeling ill even if you aren’t prone to seasickness!

Once the dive is underway, you should be over any effects of seasickness, but if you do take a turn for the worse and the urge to chunder becomes too much – keep your regulator in your mouth! Yes, you can throw up through your second stage. No, it is not pleasant, but at least when you retch and then take involuntary gasps, you will get air, albeit not particularly tasty air. Once you have finished being sick, you can calm yourself down, swap over to your octopus while you give your primary a good purge and slosh about to clear away any final bits of barf debris, then go back on to your original second stage and continue the dive. Do not under any circumstances take the reg out of your mouth while you throw up.

If you suffer terribly from seasickness and the thought of going on a boat fills you with dread, then you might be better off sticking with shore diving. As you will have seen from our top shore dive video, there are many places around the world where you can dive world-class sites without ever setting foot on a boat. But I’d urge you to try all of the above before you ditch boat diving forever – you are shutting yourself off from some amazing diving destinations.

Dan's Smart Guide of Safe Diving

Howard Ratsch — Thu, 23 Dec 2021 14:29:34 GMT

Educational Blog

DAN would only allow this to be downloaded via PDF. Use the link at bottom.

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

DAN’s Smart Guide to Safe Diving

Learn safety guidelines
Become conscientious and responsible divers
Prepare smarter so we can enjoy our dives

Here are the top seven mistakes to avoid:

Download this guide (PDF)

What To Do When You Run Out Of Air While Scuba Diving | Scuba Diving

Howard Ratsch — Mon, 22 Nov 2021 13:11:44 GMT

What To Do When You Run Out Of Air While Scuba Diving | Scuba Diving

By Scuba Diving Editors

This article represents the views of the authors. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

What should you do if you run out of air? This has always been one of the most frequently asked and significant questions for new and experienced divers. Even more so today. Not because the answers have changed, but rather because our understanding of the out-of-air situation and the way divers are equipped has evolved. As a result, the choice of which ascent you make and how you make it may be different today than it was years ago.

Are You Really Out of Air?

Probably not. What you sense as an out-of-air situation is usually a low-on-air situation. Indeed, in nearly all scuba accidents, the victim still has air and the regulator still functions. What usually happens is that a diver breathes his air supply down so low that the regulator can no longer provide air at the effort level required by the diver. In theory, this occurs when ambient (surrounding) pressure equals tank pressure. At 100 feet, this would be about 60 psi. Regulator studies and diver experience have shown that because of the mechanics and maintenance of regulators, diver breathing habits and rates, and the inaccuracies of submersible pressure gauges, the diver will feel out of air at a tank pressure higher than ambient pressure and that this disparity increases with depth. It's not as simple as that, though, because regulators reduce cylinder pressure in two stages, and because of breathing habits, exertion levels and so on. These are among the reasons why the current practice is to surface with 500 to 800 psi remaining rather than 300 psi.

Equipment or Human Failure?

Equipment can fail, but does so rarely. With a regulator, failure usually takes the form of an air leak, a water leak or a free flow. If there is a problem with the regulator, it usually still delivers air, creating an inconvenience rather than a serious situation. In spite of what textbooks and instructors might say, we do not learn to make emergency ascents because of the possibility of equipment failures, but because 99% of the time the errors are human errors. This significant fact does not change the ascent options available, but it may change which options the diver chooses and how that ascent is performed.

The Power Inflator

The use of power inflators and alternate or octopus regulators has become nearly universal. Both have a significant bearing on emergency ascent choices. A little-known fact about power inflators is that they will continue to function at a lower tank pressure than that at which a diver can comfortably continue to breathe from a regulator. At low tank pressures and greater depths, the flow rate is slower, but the power inflator still works even when the demand-valve regulator produces an out-of-air sensation for the diver. It's important to note that if you're at or nearly neutral, you don't need BCD air added anyway. As soon as you start up, buoyancy increases just like on any ascent. You may however need to orally inflate once at the surface to get enough buoyancy.

Don’t Forget To Inhale

Another misunderstood rule concerns breathing during ascents. It sounds so simple in the textbooks: “Always exhale while you ascend.” But this is only half the story. The only way you can hold your breath during an ascent is to do so forcefully, as what happens in a state of panic.

Otherwise, a relaxed diver is continuously venting. Excess air will flow out of the lungs as long as the airway is kept open through inhaling or exhaling. Continuing to breathe in and out is the best possible way to surface, as it is closest to a normal ascent. Ideally, you do not want your lungs to approach being either full or empty.

Speed Rules

In low-air or out-of-air situations, the speed of ascent is not nearly as important as was once thought. With healthy lungs and a clear airway (normal breathing/exhaling), divers can ascend at remarkably high speeds without significant risk of lung overexpansion injury. Today the recommended normal ascent rate is 30 feet per minute. Yet during out-of-control ascents performed while testing BCs, members of ScubaLab have achieved rates of 540 feet per minute, and the Royal Navy has achieved even higher rates, both with no harm to the divers. The point: ascent rate is more critical to avoiding decompression sickness than lung overpressure. While avoiding it should always be a concern, DCS is less of a danger than having no air to breathe at depth. Of course, using a buddy’s alternate air source can eliminate the need to ascend quickly.

Out-of-Air Options

Whether you take independent action or dependent action depends primarily on three factors: your gear configuration, your depth and your proximity to a properly equipped buddy.

INDEPENDENT ACTIONS

Option 1: NormalAscent

Or as normal as possible. This is the easiest and safest way to surface when low on air. You can push off the bottom, kick and use the power inflator on your BC. Remember, more air will become available from the tank, from the regulator and from within your body as you ascend. Also, your buoyancy will increase as the air in the BC or dry suit expands, or as your neoprene suit expands. With the additional air that becomes available, you will be able to continue breathing on the way to the surface. With the additional buoyancy, you may even need to dump air from the BC and/or flare (stretch out your arms and legs as wide as possible and arch your back so you face the surface) to slow the ascent. The ascent should be made with as much control as possible.

Option 2: Emergency Swimming Ascent

An emergency swimming ascent is similar to the normal ascent, but faster, so you have less control.

Option 3: Emergency Buoyant Ascent

If for any reason you feel you can’t make the surface by swimming and using the BC, then simply ditch your weights. The ascent now becomes an emergency buoyant ascent. You will go faster and have less control, yet you can still breathe in and out, dump air from your BC and flare as necessary. Emergency buoyant ascents are a faster and surer method, but they are not nearly as fast as some divers believe. You can still slow down (but not stop) and you do not pop out of the water as you arrive at the surface. With all these ascents, the key is to look up, relax and continue breathing in and out.

DEPENDENT ACTIONS

Option 1: Redundant Air

Redundant air systems, such as a pony bottle or Spare Air, eliminate the need to share air and can be used by more than one octopus. If you or your buddy has one, it should be your first choice.

Option 2: Sharing Air

If your buddy has an alternate air source, is closer than you are to the surface, and you have an agreed-upon plan, then go to your buddy and share air. You may also need to use an alternate air source because of an obstruction preventing a direct ascent to the surface, such as swimming in a wreck, under heavy kelp, inside a cave, under ice, needing to decompress, or being at great depth. Remember your power inflator will still work while you are using your buddy’s alternate air source, so each of you can become neutrally buoyant and then make a controlled ascent using buoyancy to assist you.

Option 3: Sharing Air (Buddy Breathing)

Buddy breathing should be your last resort. This is an obsolete skill that is still taught in some classes. Many divers do not understand how much easier it is to make an independent ascent (normal, emergency swimming or emergency buoyant) or to use an alternate air source or redundant system. The skill of buddy breathing is far too difficult for most divers to be able to remember and use under stress while ascending. Accident reports indicate that we’d be better off if we never have to attempt buddy breathing in an emergency. Divers have an obligation to equip themselves properly, and that means having access to an alternate air source on every dive.

Subscribe to Scuba Diving (buysub.com)

Tips for Scuba Diving in Low Visibility

Howard Ratsch — Fri, 22 Oct 2021 17:12:31 GMT

Tips for Scuba Diving in Low Visibility

How to improve your skills and make the most out of poor viz.

By Eric Michael June 22, 2019

Pro Tips for Low Visibility Scuba Diving | Scuba Diving

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Perfect is a shifting base line, especially when it comes to diving. Despite the challenges of raging current, bone-aching cold or snotty visibility, some among us can find the best in even the worst. Those silver-lining divers can be an envied bunch, enjoying the messiest of conditions like it was a screensaver fantasy. However, this relentless optimism isn’t necessarily an innate ability. Perspective is completely relative. And making the most of the marginal can be a learned skill. Just ask Glen Faith.

“The first two years of my diving career, I didn’t know you could even see underwater,” says the former Illinois Secretary of State Police diver, who now owns and operates Mermet Springs, a popular quarry site and full-service scuba training facility in southern Illinois. “I thought a mask was just something to keep the mud out.”

Becoming a certified search-and-recovery diver meant feeling his way through murky farm ponds and performing skills in near-blackout situations.

“It was diving by Braille. You couldn’t see a thing,” Faith says. “I guess the instructor trusted us when we did our skills because I don’t think he could see us.”

Thankfully, almost 24 years of finding guns, stolen cars and sometimes bodies in highly challenging marine environments from lakes to the Mississippi River didn’t ruin his enthusiasm for diving. Today, his former limestone quarry, which features sunken attractions—including a 727 passenger jet from the 1998 film U.S. Marshals, a full-size train car, a fire truck, a pedal-powered submarine and a submerged petting zoo—draws more than 6,000 divers annually to get certified and share the love of diving.

Tips for Scuba Diving in Low-Visibility or Silt-Out Situations

“The first time I breathed underwater, I never wanted to come back up,” Faith says. “It was one of the most addictive things I’ve ever done in my life. If I could live underwater, you’d never see me again.”

Faith is definitely a glass-perpetually-overflowing type of diver, a living example of the adage that the best diver is the one having the most fun—even if he can’t see much. From his example, we can all learn lessons about how to prepare for and get the most enjoyment from less-than-optimal conditions. So, when the pristine, 100-foot visibility you anticipated turns out to be a cloudy, can-barely-see-your-hand-in-front-of-your-face kind of day, try these simple hacks.

Pack a positive attitude

The most important piece of your foul-visibility kit is your own attitude. Disappointment can kill a good vibe instantly, so shedding the burden of expectation can make the difference between diving under a dark cloud or laughing through your regulator. Rather than obsessing so heavily on what might have been, focus on the possibilities—the challenge of operating in poor visibility will not only make you a better diver, it also might actually be fun.

“Anybody can dive in 100-foot visibility, but the challenge of diving where you can barely see your fins or you have to use a light to see your gauges—that’s another level,” Faith says. “People who practice in reduced visibility are really opened up to a lot more diving opportunities. Sometimes when the viz is blown out, that’s when some of the coolest marine life come out of hiding.”

According to Faith, the right training can seriously improve your outlook. A night diving or limited visibility specialty course will not only improve your skills and preparation, but it will also raise your level of comfort in poor conditions, which will deliver greater enjoyment.

Dive the right gear

Often the solution for a difficult problem is having the right tool for the job. Diving in poor visibility is no different.

A quality dive light is paramount for navigating, reading gauges and other critical tasks in limited-visibility situations, along with a trusty backup that can be safely stowed and easily accessed. Faith advises not to be blinded by power when choosing a torch because sometimes lumens can be outshined by ergonomics. Make sure your light fits comfortably and securely in your hand. And beyond the point-and-shoot varieties, consider a strobe for your tank.

“Not just a tank light, but a strobe light, so if you get displaced from your buddy, they can see that blink underwater and make their way back to you,” says Faith.

Color is another key factor when arming for low viz. “I dive yellow fins and a yellow mask for a reason,” he says. “When visibility is reduced, I need my students or my buddy to see me, and light colors that reflect light underwater make a big difference.”

Dive computers typically offer some type of illumination; recent advances in LED and OLED technology deliver bright, colorful displays that are highly effective in low-viz situations, as well as more affordable.

Slow it all down

The excitement of exploration can often drive divers to dangerous speeds underwater. Just like on the road, speed can quickly escalate challenging low-visibility conditions into a dangerous situation. Planning for a reduced pace on your dive—and being mindful of it during your dive—can be the difference between surfacing with a smile on your face or ending up in the back of an ambulance. Besides being safer, slowing down offers other benefits.

“Most divers, as a rule, swim too fast,” Faith says. “Low-visibility diving forces people to slow down—and even stop—to appreciate the little things along the way.”

Slowing down can also facilitate better discipline and increased performance in other important aspects of diving. Buoyancy is easier to control when you’re not kicking like mad. Your air consumption will improve. And you’ll get lost less often.

“Navigation is key in limited visibility because you can’t look out and see ahead of you for 100 feet, so your compass skills have to be absolutely proficient,” Faith says. “Sometimes you’ll have to make a midwater swim back to the dock or the boat, and you won’t be able to see anything. In aviation, it’s called flying by your instruments—and that’s exactly what you’ll be doing underwater.”

Overall, a successful dive in poor visibility requires a combination of the right equipment, the ability to slow yourself down, and an attitude optimized to make the best of less-than-optimal conditions. It might seem like a difficult equation, but the payoff will be that silver lining we all covet.

The Hack: Best Buddies

Buddy diving is fundamental. But when conditions are pristine and you can seemingly see forever, how many of us really stick to strict buddy protocol? Increasing your discipline to stay within easy reach of your buddy, communicate more often, and truly dive like a team is crucial to a successful dive in low visibility. When conditions are challenging, the added safety and redundancy that optimal collaboration provides is well worth the effort. Because if two eyes are better than one—wouldn’t you really rather have four?

Subscribe to Scuba Diving (padi.com)

Diving Tips: Save Your Breath

Howard Ratsch — Wed, 22 Sep 2021 15:00:23 GMT

Educational Blog

Dive Training: Save Your Breath | Scuba Diving

By John Francis

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Diving Tips: Save Your Breath

During the surface interval, the divemaster makes his rounds, recording each diver's air consumption. You admit to having only 300 psi left, which is cutting it a little close, though you made a slow, safe ascent and a complete safety stop.

But most of the other divers have 600, 800 even 1,100 psi left! What's up with that? Are they hanging out at the surface for half the dive? Sipping from a hidden pony bottle? Stealing from your octopus?

More likely, they've learned not to waste air. But cheer up: We can get you back in the game and save you as much as 500 psi. You need only follow three simple diving tips: 1. Think slow. 2. Think slippery. 3. And act sleepy. Now, how hard can that be?

1. Think Slow

Water is some 800 times denser than air, and your speed is proportional to the square of the energy it takes to produce it. You already know how hard it is to wade across a swimming pool, even slowly. Doubling your speed requires about four times as much energy. Or turn that around: Wading across the pool half as fast takes one-fourth as much energy.

So go slow. Swim slow, turn slowly, reach slowly for your console--do everything in slow motion.

Several changes to your normal pattern will save energy and air, but swimming slowly is the obvious air-saver. Also, don't forget to move your hands, arms, head and torso slowly. Unless you pay attention, you'll try to make movements at "normal" speeds, which, having been learned in air, are too fast under water.

Other Ways To Go Slow

Duck currents. They're usually weaker at the bottom or along a wall.
Use your hands. Where appropriate, pull yourself rock-to-rock, hand-over-hand, across the bottom. (Don't touch coral and other living things, of course.)
Stay warm. Your body burns calories and consumes oxygen to generate heat, so conserve it. Wear a hood or beanie, even in warm water.
Make short fin strokes. Besides finning slowly, keep the strokes short. Wide fin strokes move a lot of water but give only a little more propulsion.
Get better fins. Some fins are more efficient at translating muscle power into movement. A good pair means you'll kick with less effort, and less often.
Be physically fit. When even a slow speed is an all-out effort, you'll burn more energy than a fit diver for whom the same speed is easier. The more fit you are the more energy-efficient (and air-efficient) you'll be.

2. Think Slippery

Save energy and air by reducing drag. It's no coincidence that fish, whales and seals have smooth bodies with very few appendages. Divers, by contrast, start out with long, lanky appendages, then load themselves down with lots of bulky gear. Masks, BCs, tanks and the rest of it present rough, complicated shapes that cause lots of turbulence and drag.

There are many steps you can take to streamline yourself, but if you do only one thing, do this: Fine-tune the amount of lead you carry and where you carry it. Your goal is neutral buoyancy with minimum BC inflation and a perfectly horizontal position. This will allow your torso, hips and legs to follow through the "hole" made in the water by your head, shoulders and the end of your tank, while enlarging it as little as possible.

If you are negative, for example, you will have to fin yourself upward a little, as well as forward, to maintain a constant depth. You'll look like a "tail-dragger" airplane taxiing on the runway: Your feet and legs will be lower than your shoulders, enlarging the "hole" in the water and causing drag. If you are positively buoyant, you'll have to fin downward, with the same result.

Carrying the minimum amount of weight is important because if you are heavy (the usual case), you'll have to inflate your BC to compensate for the extra lead. The inflated BC is physically bigger and enlarges the "hole" you make in the water.

Once you have the right amount of weight, you'll need to distribute it so that, without moving or finning, your body will assume a horizontal position. That's correct "trim." Many divers are heavy at the head and shoulders and light at the hips and legs, so they swim in a bent-waist, butt-up posture or with their fins high to drive their hips down. In either case, they're pushing more water aside than necessary, causing drag and wasting air.

Other Ways To Reduce Drag

Clip your console and octopus close to your body. Keep as much gear as possible in the slipstream of your body.
Adjust hose routings. Choose different ports and shorter hoses to keep hoses close to your body. Just don't make them so short they restrict your head movement or your ability to read your console.
Get a better BC. Look for the combination of fit and just the right amount of buoyancy. A BC that's too large or has excess lift will create a surprising amount of drag. An oversized model will also tend to shift, throwing off proper trim.
Fin with short strokes. Not only are shortened fin kicks more efficient, they keep your fins inside your slipstream.
Keep your hands to your sides. And keep them still.
Hide your snorkel. Strap it to your calf, tuck it under your BC, put a foldable snorkel in a pocket, or leave it behind.
Put small accessories in BC pockets. Small objects like lights, whistles and safety sausages cause disproportionate amounts of drag when fluttering in the "breeze."

3. Act Sleepy

Here, we're talking about your breathing pattern — not your sleeping habits. If you do only one thing to make your breathing pattern more efficient, do this: Breathe almost as if you were asleep — slowly and deeply. This saves air by promoting the most complete exchange of oxygen and carbon dioxide.

You might think that taking shallow breaths, as if sipping from your tank, would conserve air. In fact, it wastes air. Every breath first brings to your lungs the "dead air" that remained in your throat and trachea from your last exhalation. This dead air has a high concentration of carbon dioxide and a low concentration of oxygen. The high carbon-dioxide concentration triggers the urge to take another breath, even before you need more oxygen.

Deep breaths, on the other hand, dilute the dead air with fresh air and deliver more oxygen to the lungs. That not only promotes quicker gas exchange, it also delays the urge to take another breath. A tank lasts longer when you take deeper breaths because you need fewer of them.

Breathe slowly too. That increases your uptake of oxygen and your discharge of carbon dioxide simply because each breath stays in your lungs longer. It gives more time for gas molecules to pass between the air sacs in your lungs and your bloodstream.

Other Ways To Breathe Sleepy

Exhale completely. This reduces the "dead air" volume and eliminates as much carbon dioxide as possible, thus delaying the urge to take another breath.
Pause after inhaling. Use your diaphragm to hold air in your lungs a few extra seconds while keeping your throat open. This allows even more time for gas exchange. Your breathing pattern should be: Exhale, inhale, pause. Exhale, inhale, pause.
Note: Every time we describe this breathing pattern, someone writes us, "Isn't this skip breathing?" It's not. Skip breathing involves holding your breath by closing your epiglottis (like when you grunt) and holding it for much longer. Closing your throat creates a closed air space that is vulnerable to embolism if you ascend. Keeping your throat open avoids that risk. Besides, skip breathing doesn't work. Holding your breath too long means retaining too much carbon dioxide, triggering the urge to breathe sooner than necessary and resulting in rapid shallow breathing. The net result: You use more air by skip breathing, not less.
Buy a high-performance regulator. With the best models, considerable engineering has gone into reducing the work of breathing induced by the regulator itself.

Comparing Gauges
If you finish the dive with less air than the next diver, does it really mean you aren't as skilled or experienced or in tune with nature?

Maybe, but it's just as likely you're bigger than the other diver. Or that you followed a slightly deeper profile or carried a camera. Or that you have different genes. It might even mean that somebody's pressure gauge is inaccurate, or that somebody's tank got a better fill.

Sure, if you use 1,000 pounds more than your buddy on the same profile, you've got a problem you should correct. But a 200- or 300-pound difference? It's meaningless.

And when faced with a choice between cutting into your 500-psi reserve or cutting short a safety stop — cut into the reserve. A safer profile is more important than a well-intentioned guideline. Just do a better job of gas management on the next dive.

Subscribe to Scuba Diving (buysub.com)

How To Identify Decompression Sickness — AKA The Bends

Howard Ratsch — Mon, 23 Aug 2021 18:08:50 GMT

How To Identify Decompression Sickness — AKA The Bends

By Scuba Diving Editors

This article represents the views of the authors. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

"I'm bent." They're the two hardest words any diver ever says. But denying the symptoms of decompression sickness (DCS) could mean you end up with the four hardest to hear: "Can never dive again."

Relaxing at the pool after a morning of diving, you notice a nagging ache in your shoulder. Is it DCS or a muscle strain from lugging gear bags? Time for a little self-diagnosis:

Do I have any symptoms of DCS?

These include but are not limited to:

Joint or limb pain
Itching
Skin rash
Nausea and vomiting
Dizziness
Ringing in the ears
Extreme exhaustion

Clearly, these symptoms are not specific to DCS, so move to the next question:

LEARN MORE: The ABCs of DCS

How Likely Are These To Be Symptoms of DCS?

You did only a single half-hour dive to 40 feet that morning — how could it be DCS? Easy: during the last five days you’ve done 15 dives. The more diving you’ve been doing, the more likely it is to be DCS. The more you’ve pushed the edge of no-decompression status, the more likely it is DCS. The more safety stops you’ve blown off, the more likely it is to be DCS. Any of those apply?

I'm Still Not Sure. What Can I Do?

This is easy: Call DAN’s emergency number (+1-919-684-9111) if you need some expert assistance

in deciphering your symptoms. DAN has doctors on call 24 hours a day who can help you arrive at a decision about your symptoms.

I Know I Have The Bends. What Should I Do?

Start breathing oxygen and have someone call DAN’s emergency number immediately: (919-684-8111). The DAN staff can help you arrange for transportation to the nearest chamber. DAN will help you even if you have not purchased DAN insurance, but you won’t like the five-figure bill you may have to pay. Or the possible delay in emergency evacuation because the helicopter company wants its money up front since you don’t have insurance, Considering how little we actually know about the mechanism of DCS, anyone diving without dive accident insurance is taking unnecessary health and financial risks.

Subscribe to Scuba Diving (buysub.com)

Safety Tips for Diving During COVID-19 | Scuba Diving

Howard Ratsch — Thu, 22 Jul 2021 18:54:09 GMT

Educational Blog

Safety Tips for Diving During COVID-19 | Scuba Diving

Advice from PADI and DAN on how divers can get back in the water safely.

By Alexandra Gillespie

This article represents the views of the authors. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Stay six feet apart on land.

Maintaining social distancing while topside will help reduce the risk of transmitting coronavirus when diving.

Scuba divers around the world are eager to get back in the water. As operators reopen globally, PADI is encouraging divers to #DiveLocal.

To help divers prepare for the new reality of diving during COVID-19, PADI and the Divers Alert Network (DAN) each recently issued advice to dive operators on how to safely resume operations.

While this guidance gives divers an inkling of what they can expect when returning to their dive shop—reduced boat capacity, a possible disappearance of communal rinse barrels and simulated air sharing in training courses—the best practices also include ideas for what divers can do to keep the industry healthy and operating.

Please note: While these actions can reduce the likelihood of coronavirus transmission, the risk cannot be entirely eliminated when interacting with other people.

Stay distant at the surface

Stay six feet away from other divers until you are underwater, such as when riding a boat out to the drop, checking your buddy’s kit or renting equipment. This means, for example, you should inspect your buddy’s equipment visually before getting in the water, but not reach out to adjust any of their straps.

Keep at least six feet between you and other divers when in the water as well until you are securely below the surface. Once submerged, “breathing from scuba substantially reduces respiratory transmission concerns,” says PADI in the best practices document posted on the PADI Pros website. “This is obviously important underwater because close contact is important for safety, control, skill conduct and maintaining buddy contact.”

Kit up solo

Putting on all of your equipment by yourself enables social distancing and minimizes the number of people who touch your gear. Sitting on a bench or putting on your BCD once you are in the water will make this easier. It may become a necessary skill—tour operators, usually happy to help you wrangle equipment into place, are being advised not to touch customers or their gear if it can be avoided.

Diving with a member of your household allows more interaction with your buddy, like kitting up or sitting by each other on a boat, as “couples, families and others already socially exposed to each other have more latitude in distancing/contact restrictions,” says PADI on the basis of broadly accepted best practices.

Breathe through regulators in close quarters

Some situations require proximity to other divers when at the surface, like dealing with a panicked diver or doing a tired diver exercise. While a regulator does not protect those around you from your exhalations, warns PADI, breathing through your regulator allows you to pull from your tank air, reducing the chance of inhaling respiratory particles floating around you.

Wash or sanitize hands while topside

“Divers should avoid touching each other's gear, but sometimes it is necessary before, during or after a dive,” says PADI. “The best practice is for divers to wash/sanitize hands before and after touching their own and someone else's gear, meaning before and after the dive in most instances.”

Exercise caution with sanitizer around canister fills

Frequent disinfection of hands and equipment is key to limiting transmission. But DAN warns divers to keep alcohol away from canister fills in order to avoid accidentally igniting a fire.

“Note that alcohol-based hand sanitizers are incompatible with compressed gas,” DAN says in its online FAQ. If you are filling your own tank, “alcohol-based substances should not come into contact with...cylinders and fill whips that are used with any compressed gas but especially oxygen-enriched gas. This would increase the risk of fire and explosion due to the high volatility of alcohol and its ability to ignite at relatively low temperatures.”

Washing hands with soap and water is a far preferable route. If hand sanitizer must be used, DAN urges divers to make sure their hands are “completely dry and all alcohol has evaporated.”

Smear defog, not saliva

Some divers swear spit clears a mask better than any defog. That debate will have to wait. Spitting nearby other people—especially into a rented mask—could increase the risk of transmitting coronavirus. Rely on defog for the foreseeable future to get a clear view underwater.

Watch where you’re pointing that snorkel

Coronavirus can pass through respiratory droplets carried through the air. PADI advises keeping an eye on where the wind is blowing and in what direction other divers are breathing. After surfacing, divers should separate to at least six feet before switching from a regulator to a snorkel, which should only be used when pointed away from other divers. When on a boat, wear a mask over your mouth to mitigate the spread of coronavirus from wind off the water or from the movement of the boat.

Limit trying on rentals

If the operator is properly sanitizing rentals, they should be safe to use. Nothing is foolproof, however, so only try on multiple pieces of rental equipment when strictly necessary. This restricts how much rental equipment you are exposed to, and, respectively, how much equipment you contaminate that could expose other divers.

Dive conservatively

Diving beyond your limits or absentmindedly can cause an emergency. Common emergency procedures, like sharing air or performing CPR, bring divers in close contact and swaps saliva, increasing the chance of transmission. Dive well within your limits to avoid forcing a close encounter.

Subscribe to Scuba Diving (buysub.com)

In which part of the scuba diving industry should I invest?

Howard Ratsch — Tue, 22 Jun 2021 12:36:27 GMT

Educational Blog

In which part of the scuba diving industry should I invest? | by Darcy Kieran | Scubanomics | May, 2021 | Medium

This article represents the views of the authors. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Updated on May 31, 2021.

The scuba diving industry has been hit hard by the coronavirus pandemic and was already facing copious challenges before this ordeal. But running for the hills is not always the only choice in difficult times! In many cases, problems are opportunities — for real! I believe it is the case in the dive industry.

Our biggest opportunity lies in redesign the scuba diving industry business model using a blue ocean strategy. It’s also a big challenge!

But it will happen, so… Where should I put my money to be ready to benefit from a ‘new’ dive industry? Better yet, in which part of the scuba diving industry should I invest if I want to be part of the solution and cash in on a renewed growth trajectory?

Disclaimer

Before getting any further into this discussion, let’s clarify that the information contained in this article is not intended as, and shall not be understood as construed as, financial advice. I am not an attorney, accountant, or financial advisor, nor am I holding myself to be. The information contained here is not a substitute for financial advice from a professional who is aware of the facts and circumstances of your individual situation.

Furthermore, in this article, I am looking at investments in different parts of the scuba diving industry, at the macro level, not in particular companies, even if I use some of them as examples of general concepts.

Macro-Trends That Will Lead Growth in The Scuba Diving Industry

For real growth to happen in the dive industry, we need a renewed focus on the experience of scuba diving and much less on c-cards (certification courses) and dive gear which is simply a means to an end.

Currently, our business model relies on local dive shops as the entry door into scuba diving. And for dive store owners to be able to pay the rent and buy groceries for their family, they must sell courses and dive gear. It explains why the dive industry focus has been so much on selling courses and scuba equipment. Local advertising for dive shops is usually about dive certification courses, and competition between dive centers is usually on the pricing of courses and gear.

This model doesn’t work anymore for all the reasons we’ve discussed numerous times in Scubanomics. For the dive industry to grow, we need to adapt to today’s consumers' expectations and deliver experiences worth reliving over and over again instead of peddling c-cards to people who wanted to cross that off their bucket lists.

In fact, we shouldn’t be so focused on the words “scuba diving.”

Hiking doesn’t advertise itself as “walking.” In our case, scuba diving is like walking — it’s a way to do something else. And that “something else” may be many different activities, including discovering reef fish (the equivalent to bird watching) or visiting deep wrecks (much more adventurous).

The market is not homogeneous. People have different interests and aspirations. There may be many different reasons why people would be drawn to experiencing the underwater world. And strictly promoting the act of breathing underwater (which is what scuba diving is) will leave a lot of potential clients behind.

We need to identify these motivations and advertise them — not “scuba diving” — just like bird watching is not promoting walking and breathing. Scuba diving needs to become an “oh, by the way, we need to be scuba diving to do that.”

Similarly, we should stop talking about “the dive industry” and talk about “the underwater world industry.”

In such a renewed focus, where will current stakeholders stand? Who will gain and who will lose?

Scuba Diving Certification Agencies

As we analyzed before, dive training agencies currently maintain a chokehold on the rest of the dive industry. In our Porter’s Five Forces Analysis of the Scuba Diving Industry, we concluded that dive training agencies were extracting and pocketing an inordinate proportion of the dive industry value chain.

It is unlikely that they can maintain such a position and even less likely improve on it. No matter how much we squeeze a lemon, there is a limited amount of juice in it! That’s why we see dive training agencies fighting over market shares in a desperate attempt to please their shareholders during this fiscal quarter. They are not growing the industry.

On top of that, we believe that a renewed dive industry can only be built on a much lesser focus on issuing certification cards. It is not inconceivable to think of a world where there wouldn’t be much more than an entry-level certification course in recreational diving (not talking of tech diving).

The rest of the dive abilities could be developed by spending more on experience and less on the training material.

All arrows point toward dive certification agencies losing their grip on the industry. In fact, it may be a requirement for significant growth for the rest of us. It’s the last place I would currently invest money. We’ve seen numerous private equity firms rushing to throw money at them, but that was based on a very traditional look at past results.

Footnote: These observations are based on the certification part of dive training agencies. These companies could do well if they diversify away from relying on selling course material and online access to training. We see PADI heading in that direction with their acquisition of Bonnier publications and Diviac. They appear to be focused on pocketing more profits from the “activity” of scuba diving by selling dive experiences directly to consumers in competition with local dive shops. I think we can expect further developments in that direction.

Dive Gear Manufacturers and Brands

In a world where our focus is on a wider segment of the population casually experiencing the underwater world, selling dive gear to scuba diving fanatics will no longer be front and center.

Our traditional core market in the dive industry has been — and to a certain extend, remains — the baby boomers. For them, scuba diving was a lifelong dream, and once they learned to scuba dive, they defined themselves as scuba divers. They went on dive trips in which there was nothing else to do but scuba diving and drinking beer.

The younger generations tend to “do” scuba diving without “being” a scuba diver.

They could be interested in visiting the underwater world once or twice in a trip that also includes hiking and stand-up paddling.

This new generation will not travel around the world with a huge duffel bag of heavy scuba gear for a day or two of diving here and there.

We already see a trend toward fewer dive gear sales. On top of a reduction in the number of dive certifications, we see fewer dive gear sales per new student diver trained. Therefore, the future is as bleak for dive gear manufacturers as it is for traditional dive training agencies — if they do not adapt.

But there are new opportunities on that front.

First, we can expect a growing demand for dive adventure operators to provide quality rental gear. We will come back to the importance of consistency in the quality of the experience in the next section, and what opportunities it will create for dive gear brands.

Second, I would invest in a company focused on redefining dive gear to help bring more people to experience the underwater world.

Future dive gear needs to be lighter, easier to use, and much more “cool”.

Nothing has really changed in the basic configuration of the scuba unit in years. Well… Somebody, somewhere, will innovate — and cash in.

One glaring example is surface-supplied air (SSA) that we discussed recently. It looks pretty good on the Eliminate-Reduce-Raise-Create Blue Ocean Strategy’s grid. And with the introduction of the battery-operated surface-supplied air units, SSA gives us a very convenient way of providing air to people underwater for them to experience “the first atmosphere” (up to 10 meters/30 feet), which is where most underwater tourists will find interesting stuff to see and do.

It means that a good investor would keep an eye on innovative companies like Brownie’s Marine Group. It is notable that they had a 53.5% increase in revenues in 2020 — unlike the dive industry! And just like the rest of the outdoor industry!

A good way to make money, in the long run, has always been to invest in innovative companies at the start of their innovation cycle. Remember Apple? Google? Just saying!

In parallel to that, we have companies providing very specialized dive gear like rebreathers and other tech diving equipment. This market should remain a valid one. It’s the casual recreational scuba diving segment that is most likely to witness significant changes in the short term.

With that kind of pressure on recreational dive gear brands, we can expect further diversification and consolidation — which has already been happening very aggressively over the last 10 years.

Diversification is like the recent acquisition of the triathlon wetsuit company Aquaman by French dive, snorkeling, and freediving brand Beuchat. Consolidation is like the acquisitions of Atomic Aquatics, Zeagle, Bare, Hollis, Stahlsac, and Oceanic by Huish Outdoors in Salt Lake City, Utah.

What does it mean in terms of investment?

Whenever a company acquires another one, the shares of the acquiring one drop while the shares of the acquired one jump up in value. We see that in the stock exchange almost every day.

Therefore, a good investment strategy in dive gear brands would be to place money into smaller dive gear manufacturers, especially if they provide something unique — like SSA and dive computers — something that a larger dive gear brand would benefit from adding to their product line-up.

Another option is investing in regional dive gear brands. For instance, a Huish Outdoor is firmly established in the USA but lacks a solid presence in Europe. I would not be surprised to see Huish acquiring a company well-positioned in Europe but with a weak presence in the USA. This could be a Beuchat or a Poseidon, for instance.

Disclaimer: I have no financial investments in any of the companies mentioned above, and I used them only to represent a general idea and direction.

Dive Travel

Dive travel is very segmented at the moment. Numerous travel agencies are specializing in scuba diving adventures. The destination can be one of many dive resorts or liveaboards. Local dive shops also sell dive travel. And any tourist resort or regular travel agency can add scuba diving to their offerings.

Scuba diving can be done anywhere there’s water, and therefore, the dive operators will most likely remain a series of independent operators. The biggest opportunity on this front is not on consolidation or vertical integration.

The two biggest opportunities on this front are related to diversification and branding.

Diversification means offering more than scuba diving, as we discussed above. Growth would come if we manage to offer the experience of the underwater world to a wider segment of casual divers. This can be achieved by providing the experience in more destinations outside the traditional dive-focused resorts. Surface-supplied air units could be a useful tool to achieve this goal, as is the development of a reliable brand.

Consistency in the quality of the experience has been a recurring problem in the dive industry. It fuels a huge drop-out rate, as we have seen in a recent Scubanomics survey on scuba diving and snorkeling.

Therefore, the biggest opportunity in dive travel — and the dive industry as a whole — is the development of a trusted brand offering consistency in the quality of the experience at all locations operating under its flag. I do not see any company currently investing in that direction. That is what I will keep my eyes (and wallet) open for!

Dive Gear vs. Dive Travel

Consistency in the quality of the experience means that I would expect quality dive gear at every location. Not only that, I would expect the gear to be pretty much the same so that I know how to best operate it — and I know that a size ML Tall is what I always fit best into.

That requirement for increased reliability in the quality of the experience and the fact that younger generations tend to be more casual divers, open up an opportunity for a dive gear brand willing to satisfy these needs. For instance, here is one: a rental dive gear system allowing divers to have access to the same gear everywhere they dive, without having to travel with it and without having to take care of the annual maintenance.

Time to think outside the box!

Local Dive Shops

Traditionally, local dive shops have been the entry door to scuba diving. Yet, they’ve also been the weak link.

I don’t want to insult anybody here! I owned and operated dive shops, and I know how difficult it is to offer quality in all six of the business units we try to operate under one roof: a school, a retail store, a travel agency, a fill station, a garage for dive gear, and a rental business.

A local dive shop is a tiny business, and that level of diversification naturally leads to sub-par performance in all 6 business units.

On top of that quality issue, these small businesses do not have the financial means to maintain a level of dive gear inventory that would satisfy today’s consumers.

Therefore, the opportunity on this front relies on a complete re-design of the business model.

Purchasing or investing in a local dive shop is not a smart money move at the moment — if it ever was!

If I want to offer scuba diving in an urban (non-tourist) location, I would invest in developing my personal dive instructor brand around the quality of the experience and forego selling dive gear.

Eventually, training agencies and dive gear brands will all be selling directly to my clients. Therefore, the investment should be in my personal brand (my name), not on promoting PADI, SSI, Aqualung, 10W30, or XYZ.

Once a global brand has established itself as the one providing consistency in the quality of the experience (as discussed under dive travel), that is the brand I would want to operate under and invest into.

The only big investment needed in this local diving scenario is a fill station, but we can skip the heavy gear inventory and the expensive commercial lease. And if the market is too small for a full-blown fill station, I would look at surface-supplied air units and/or portable compressors.

Summary: Investing In The Dive Industry

I would not invest in:

· Traditional dive training agencies

· Large, established, and non-innovative dive gear brands

· Local dive shops

· Dive resorts offering only scuba diving

I would invest in:

· Innovative dive gear brands

· Specialized dive gear brands

· Dive gear brands with a strong presence in a region not well serviced by large brands

· Locally: My personal dive instructor brand (my name)

And the big investment would be in a project to develop a global experience brand offering consistency in the quality of the experience.

Let’s make a good living out of our passion for scuba diving!

Don’t be left out: Subscribe to be the first to know about dive industry news and market data.

Continue reading: Scubanomics Table of Content.

Be our dive business buddy on LinkedIn | Twitter | Facebook | Elsewhere

Check our list of suggested business management books for dive professionals.

Sign up for Scubanomics: Scuba Diving Industry

By Scubanomics

The dive industry is facing many challenges and exciting opportunities. Let's redefine our business model around today's consumers expectations. We will let you know when new topics are available. Take a look.

Get this newsletter

DOES SCUBA DIVING AFFECT MENTAL HEALTH

Howard Ratsch — Sun, 23 May 2021 15:54:24 GMT

Educational Blog

DOES SCUBA DIVING AFFECT MENTAL HEALTH

By Oyegoke Motolani Oluwakemi

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Presently, the concept of mental health is under investigation. What we know for sure, regardless of your age, size, or societal status — it can affect anyone. Therefore, it’s tasking for medical professionals to give concise advice on this issue. The ideal mental health involves a natural ability to live out individual potential; this includes facing the usual stress associated with being human, productivity, and daily work. The ideal mental health is not limited to being productive; it involves being socially balanced, professional, and socially engaged, etc.

Mental health levels can be described based on a spectrum ranging from healthy to adverse or ill. Hence, there’s usually a variation — short-term and long-term mental illnesses. Still, the effects may vary in individuals such that a person with a poor mental health condition like anxiety disorder could be fully functional in their daily lives. To cushion the effects of adverse mental health, professionals advise socializing. In adherence to such opinions, people embrace physical interactions with the environment, and other individuals, thus embracing scuba diving.

Scuba diving does not take place in a natural human environment, so taking precautions is necessary. While the thrill of diving into the water brings out people’s adventurous side, divers usually overlook their mental health. However, due to the impact outdoor activities have on an individual’s overall well-being, people with mental health concerns naturally embrace the activity.

A study conducted by the University of Sheffield’s Medical School supports the claim that diving impacts levels of anxiety, depression, and social functioning. The report also claims that scuba diving can provide several therapeutic benefits to improve social dysfunction and depression. The study sheds light on scuba diving as a potential therapeutic aid, while demonstrating the positive impacts it poses. How does it work?

Physical activity

Anyone who recognizes that they have mental health challenges must have spoken to a professional and counselor. It is, therefore, not uncommon to receive recommendations of participating in physical activities.

However, for many people, running and other kinds of physical activity turn out boring. It doesn’t take too long for discouragement to set in, and so, physical activity comes to an abrupt end. Local sports or Zumba classes make nice alternatives, but you tend to expend more energy.

Scuba diving is essentially moving slowly underwater. As you begin to dive, you put your muscles into work by swimming and slight body adjustments. But, in the end, you’re doing something that improves your mental health.

Mindfulness

Breathing is the core of diving, just as it is for living. It happens instinctively, so that movement in water is seamless. What you’re doing in the real sense is focusing on your breath and its rhythm. Diving has more merits than demerits. All divers actively engage their minds in the activity while underwater. They make clear decisions and effectively manage events. None of this is possible without involving the mind.

Since breathing is the biggest part of diving, you learn to focus your breathing by inhaling and exhaling in a meditative way. Meditation is a fundamental aspect of yoga which comes in handy and helps your mind retain calm. When underwater, you’re surrounded by a peaceful kind of calm and silence that allows you to flow with the current environment. Your mind presently drifts away from external concerns so that you can enjoy your space and sport.

Easy Socialization

A major symptom of adverse mental health conditions is the affected person’s inability to talk to people or maintain social interaction. Networking for such people is almost impossible because they tend to hide and isolate themselves. Sometimes, changing environments is tough since it equals a potential association with new people.

Scuba diving is an easy way to come out of this state. It brings people of different races, classes, and calibers together without fear or judgment. Regardless of where you’re from or when you’re diving, you speak one language — the language of the sea. The amazing part is that you don’t have to say a word. There is a common ground and an avenue for people to bond and enjoy the sport.

Socializing while underwater is easier with the various diving hand signals people use to communicate. Furthermore, it excludes the anxiety that often comes with speaking to people because you only need to communicate with a partner. Generally, diving is done with someone else, so you find yourself with them. Since you only need to ease into the conversation, you soon find yourself talking about other stuff and sharing without any pressure. Additionally, as these interactions grow, you begin to trust people more

The Marine life encounter

If you have ever watched fishes in an aquarium, you will agree that there’s a feeling of satisfaction with that simple act. Life underwater brings a calming effect to the heart and brain. The burst of colors and different species of aquatic life brings you delight and calm. Colors naturally lift the human mood by increasing serotonin and dopamine levels produced in the brain. Both neurotransmitters stimulate happy chemicals in the brain, hence improving the mood.

A kind of therapy

Scientists like Dr. J.C. Lilly, a neuro-physiologist, agree that water therapy is both relaxing and rejuvenating. The flotation therapy proves that weightlessness is a way to put the body in a state of total relaxation. Since scuba diving is akin to submerging the body in water, it helps clear the mind and release stress.

The human body comprises 70% water, the same percentage of water covering the earth’s surface. Saltwater opens the pores on the skin and enhances the absorption of essential water minerals. So, in addition to aiding mental health, scuba diving looks great on the skin too.

Fitness

Although the weather conditions of the location you use for your diving activity may be subject to peculiar changes, the struggle against any water body improves your strength. Often, divers move through currents and avoid collision against water reefs. These build physical fitness and improve endurance. The water workout helps your mind stay sharp and ready. Also, it helps the muscle and joints.

Conclusion

Scuba diving is relaxing and encompassing. It fosters self-reliance and therefore, it is good for individuals with mental health challenges. So, does scuba diving affect mental health? Yes, and positively too. It’s time to explore the numerous advantages of scuba diving. If you intend to go all out and embrace something new, scuba diving is a great idea. I recommend you try the waters of Miami and have all preparations taken care of beforehand. Here’s a chance to sharpen your senses and retain your vitality while having fun too. Enjoy! Happy Diving!

Then and Now

Howard Ratsch — Thu, 22 Apr 2021 12:49:12 GMT

Educational Blog

THE DIFFERENCE BETWEEN “THEN AND NOW” IN TECHNICAL DIVING

By Michael Thomas

https://www.tdisdi.com/tdi-diver-news/the-difference-between-then-and-now-in-technical-diving/?fbclid=IwAR2f60R2T2YkRUV0GssuOaso7lqtAQOMm2SKU8HdNuNA59-uW2a4ks81XO4

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

“Have you got a light, guys?”

Many years ago, surfacing from a cave or sump dive and hearing the cry “have you got a light, guys?” was not uncommon. Diving light failure happened a fair bit, as lighting was not as reliable or bright as we have now. A team member’s light was either out or producing lumens not much better than a glow worm in a jam jar! Not really a problem if you are back at the entrance to the cave, but more of a problem if you have surfaced beyond a sump inside the cave.

Sitting at my desk, passing the time in Coronavirus lockdown, I started thinking about the equipment and techniques we used back in the 90s compared to what we use now. Was it all the bad old days? Did the skills we developed then and problems we had to overcome put us in a better place for dealing with modern long exposure technical diving on rebreathers and mixed gas today? The list of differences is long and would be very tedious to the reader. I’ve chosen eight subjects to compare that have had major changes since my diving life started in 1987.

Deep Air

This is the one old school technique every diver today knows is a bad thing — the skill set that really needs to be in the diving dustbin. A breathing gas at depths below 30m gives increasing narcosis and increasing PP02. Both of these are bad, and combined with increased work of breathing, increasing gas density, and C02, it really does not have much to offer.

So why did we use it as a deep gas?

Firstly, it was readily available and cheap. Oxygen and nitrox were not easy to get for divers, let alone helium. Plus, so few divers within the sports diving and fledgling technical diving world knew how to produce decompression tables for helium. So, for most, air was the only option for inquisitive divers that wanted to explore deeper. Exploration is a powerful driving force for some.

Now you also need to consider the attitudes of the time: going deep was deemed cool. It proved something to your peers. This was an attitude that killed many and the rest of us just got lucky. But what did we learn from deep air diving? The TDIstandards of today are based on sensible diving limits learnt the hard way by many, and I, being one of the lucky ones who survived, can teach with first-hand experience about what narcosis and gas density are all about. Deep Air: just don’t do it.

Trimix

This gas, with a combination of Oxygen, Helium and Nitrogen, has become the go-to gas for deeper diving on open circuit and now, more commonly, on rebreathers. With the correct gas mixture for the planned depth, low narcosis, low work of breathing and gas density are achieved. Today, many dive computers can compute for any gas mixture and your mobile phone contains gas mixing and decompression planning apps. The understanding behind the Decompression theory is at an all-time high, with multiple papers and blogs explaining the current thinking.

If we go back to the mid-1990s, trimix diving was very different.

We were still at the point of hiding nitrox cylinders to get them on dive boats. The primary agencies of the time, BSAC and PADI, had declared nitrox a devil gas that would kill everyone, and both the US Navy and British Navy said recreational/technical divers did not have the knowledge or backup to use trimix safely. However, we persevered. A few brave divers took the plunge, resulting in some success and also tragedy, but we carried on. Bill Hamilton would supply trimix diving tables to technical diving expeditions for a price, and eventually, Sheck Exley released a decompression planning software program called Dr X. Other notable divers followed suit around the same time and technical diving agencies were born, producing trimix manuals complete with decompression tables.

Now, our knowledge then was very different from today. When I did my open circuit trimix course in 1997, the general consensus was the need to get off the helium as deep as possible on the way up. Our lack of understanding about how helium reacts led us to believe the lighter gas, helium, would cause decompression illness if we stayed on it at shallow depths. We did some gas switches to air at around 50m after 85m trimix dives! Now, during deep CCRdives, the diver will stay on the helium in the loop all the way to the surface.

Another big change is the use of dive computers, either in open circuit mode or real-time monitoring of your CCR, with divers carrying a backup computer to give the all-important decompression information.

Now back in the 90s, we had pockets full of laminated decompression tables for the planned depth and time. We also had multiple variations of depth and time, such as deeper and longer and shorter bailout tables if you missed the wreck or had a problem on the descent. The time and depth were either recorded on bottom timers or divers would use a standard air computer and just bend the air computer on surfacing. More than once, I remember dive partners surrounded by decompression tables on decompression stops, as the homemade laminated tables fell apart and alarming air dive computers in a bucket of water on the dive deck to muffle the sound.

Independents Doubles

A twin set is now a fairly common and basic entry requirement into the technical diving world. In Europe, the standard is generally a 12l (cylinder size may vary elsewhere) steel set with an isolation manifold fitted. Regulators with longhose on the right, a single pressure gauge to the left and primary donate being the preferred option. A backplate and wing making up the complete system. Most divers preferring a Hogarthian system, keeping it clean and simple.

Back in the 90s, a lot of twin sets were independent cylinders with no manifold at all, either banded together with traditional stainless bands as you see now, or using temporary cam bands to join two cylinders together. In the early years, most independent twinsets had two right-handed cylinder valves, giving you no chance to shut down the left-hand cylinder. It took a while for the technical diving community, especially in Europe, to start thinking about shutdowns and using a left-handed valve on the left cylinder. Being able to shut down the gas supply on your own at that time was not high on the list of things-to-do. Eventually, manifolds started to become more popular, and finally, manifolds with an isolation valve became the norm, making diving safer and divers more skilled.

Fixed Sidemount

I started sidemount diving in 1992. The day I started cave diving, I was loaned a 1980s style sidemount harness. The cylinders were clamped at a single point, about a quarter of the way down the cylinder. We had different size clamps for different size cylinders. The cylinder and clamp was then threaded onto the harness belt loop along with the weight needed to dive. Regulators were then attached to cylinders. We had standard length high-pressure hoses wrapped around the first stage and valve, held down with bungee loops. The diver then had to lay the sidemount harness out on the ground, complete with cylinders, then step over it and pick it all up to get it onto their waist! With large cylinders, help was generally needed. The harness had no built-in buoyancy, so a modified open water BCD was used and worn over the top of the harness. When diving this system, back pain on long dives was very common, as the entire weight of the harness, cylinders, and lead rested on your lower back, pushing the diver into shallow V shape.

Compared to todayʼs modern sidemount harness choices, some of which are superb, with built-in BCDs, weight running down the spine and the ability to attach cylinders after the harness is on, the harness we started with is a world away. Sidemount diving is easy and enjoyable now, once you have the modern harness set up correctly. The techniques we developed have been ever-evolving. But gas management, rule of thirds and balancing cylinder pressure was done from the early years.

Lights

Having good lighting is one simple yet expensive way to improve the overall dive experience. From caves to wrecks, ocean dives to photography, lighting can make or break the dive. The other thing Iʼve learnt over many years of diving is if you donʼt want a dive light to fail during the dive, leave it at home safely in storage and make sure you have a backup light. Iʼve seen lights fail in every conceivable way, from floods to cable breaks and blown bulbs.

Modern lighting is generally very good now, with LED bulbs, high lumen output and battery technology thatʼs improved every year, giving longer burn times and smaller and smaller battery packs. Compared to what we used to use in the 90s: lead-acid battery packs that weighed around 3kg and were the size of a small diving cylinder, generally mounted on the twin set or on the right hip. Unlike todayʼs canisters, it was like having an extra stage cylinder on your harness. Large unwieldy light heads with, if you were lucky, a 50-watt halogen bulb to brighten the darkness. Between halogen bulbs and the LED bulbs of today, we had the HID bulb, which gave a greater light output but were very fragile and rather expensive to replace. They were not great for a light unit designed to be used by divers exiting a busy dive boat deck or cave diving.

Decompression

Ever since divers have started diving, decompression has played a large part in the sport and working environment for all divers. The act of allowing your body to adjust back to surface pressure after diving is still as crucial now as it was then. We canʼt beat physics and physiology.

What has changed and continues to change is our understanding of decompression and the techniques of conducting decompression dives. Understanding that all dives put you, the diver, under pressure and require at least a minimum safety stop to choose the most effective decompression gas to return from deep open-circuit dives, or what fixed partial pressure and gas to run on your rebreather, is important. A lot of technical diving expeditions now conduct post-dive medical studies on divers to build the knowledge of decompression and papers are written fairly regularly with updated knowledge. A good diver will constantly update his knowledge on decompression and make use of the information available to stay as safe as possible.

Boat Lifts

I had just finished nearly an hour of decompression after a dive in 1998 in the English Channel. The wreck was at 80m and previously unexplored. On surfacing, I floated, talking to my dive partner, whilst waiting for the dive boat to come alongside and pick us up. The sea conditions were worsening, and the skipper indicated he wanted us on board as quickly as possible. Working my way along the line on the side of the dive boat and reaching the ladder to get back on board, I placed a regulator in my mouth and started to climb. A 12l steel independent twinset on my back canister, a dive light under each arm , and 10l steel decompression cylinders are a heavy load to climb a ladder with, especially after a deep dive. On this occasion, I really struggled to climb the ladder and only realized at the top of the ladder that I had put my trimix regulator back in and not the decompression gas regulator. Not only was I trying to climb a ladder with four cylinders in a heavy sea, but I was trying to do it with a reduced oxygen percentage. Spitting the regulator out and breathing air really helped.

Today most dive boats that I use all have diver lifts. When the dive boat pulls alongside, the lift is dropped into the water, the diver swims in and places feet down and hands-on handrails, clear of the boat. A nod to the skipper and you are raised like a god to the dive deck. You have to love boat lifts. But, if a dive boat has no lift or the lift fails, then years of ladder use make this no problem, as long as the diver has good strength and fitness.

Fitness and Attitude

Back when I started diving in 1987, I was using a single cylinder, a wetsuit, and an ABLJ buoyancy compensator. It took years to progress up to twinset diving and drysuits and finally caves, rebreathers, and instructing. However, those years were not wasted. They allowed us to gain the experience and also follow the changes within sport and technical diving. We found out what worked and what did not work, sometimes the hard way. We crash-tested the standards that are the norm today.

Along the way, we realized diver fitness was crucial to stay safe in a sometimes unforgiving environment. Today diving is possible with much faster progression. Equipment is pretty much available to do most things, and the training is available to use that equipment. Whatʼs missing now is the attitude of slowing down and building on that training before launching on the next quest. A diver with a solid skills platform and experience at one level is ready to tackle the next with much more confidence and safety.

I sat at my desk writing this during very strange times. Iʼm aware that I probably wonʼt dive for some time due to coronavirus stopping the world. What Iʼm doing is keeping my physical fitness up and keeping my mind sharp by reading, research and planning some dives for when we can get back in the water. These dives will not be teaching dives. They will be easy dives to refresh myself and rebuild muscle memory for the art of diving. Stay safe guys and remember, when we can, build up slowly again.

Scuba Q & A: Common Questions Asked By Nondivers

Howard Ratsch — Mon, 22 Mar 2021 13:24:06 GMT

Educational Blog

Scuba Q & A: Common Questions Asked By Nondivers | Scuba Diving News, Gear, Education | Dive Training Magazine (dtmag.com)

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

When you tell friends and co-workers that you’ve recently been certified to scuba dive, their immediate reaction is likely to be an incredulous, “Wow. You did? I’m not sure I could do that!”

Is it hard to learn to scuba dive?

As active recreational pastimes go, scuba diving is one of the easiest to learn. While you’re gliding around enjoying the underwater sights, you’re engaged in only three basic skills: floating, kicking and breathing. Of course, there’s more to it than that — becoming proficient at using the equipment and developing knowledge of scuba concepts and safety procedures — but if you can breathe through your mouth, chances are you can learn to scuba dive.

The necessary skills are not tough for most people to master. During scuba certification class, you’re taught the effects of increased water pressure and safe diving practices. You rehearse equipment-related skills in a controlled water setting until you feel comfortable, as well as practice what to do if things don’t go as planned.

Doesn’t it hurt your ears?

This question comes mainly from folks who have snorkeled and tried to dive beneath the surface — free dive. They swim headfirst down to about 6 feet (2 m) and suddenly develop a stabbing pain in their ears, sending them shooting back to the surface. The unknowing assume that they have an ear problem that precludes them from scuba diving.

On the contrary, the problem is due to a lack of knowledge about the effects of pressure and is easily prevented. If you fly in a plane without serious ear discomfort, then your ears should not present an impediment to diving.

Increasing water pressure pressing inward on your eardrums as you descend, compressing the surface-pressure air within your middle ear, causes the pain. The remedy is to equalize the pressure on both sides of the eardrums by opening the eustachian tubes, which run from the back of your throat to the middle ear. This is done by pinching your nostrils shut, lifting your chin and gently trying to blow out through your nose. Try it now. You should hear a slight crackling sound — the eustachian tubes opening. Some divers can equalize by simply moving their jaw or tongue.

It is typically easier to equalize the ears when scuba diving than when doing a headfirst surface dive. The reason is that scuba divers are taught to descend feetfirst (air moves up more readily than down) and to equalize “early and often.” Unless your ears are stuffed by cold or allergy symptoms or you are one of the very few people born with narrow eustachian tubes, ear pain is not an issue. Trained scuba divers know that if they do occasionally have trouble clearing their ears, it’s time to skip diving until the congestion eases.

What is there to see down there?

A whole new world of incredible sights awaits the scuba diver, no matter what the underwater environment — fresh or salt water; tropical or temperate; ocean, quarry, lake or river.

It shouldn’t be hard to envision yourself gliding effortlessly through a crystal-clear tropical ocean, marveling at rainbow-hued fishes flitting about a vibrant coral reef. We’ve all been treated to underwater scenes such as this on TV, in movies or perhaps a friend’s underwater video. You may even have caught a firsthand glimpse when snorkeling in Florida or the Caribbean.

But unless you’ve spent time underwater, you can’t appreciate the wealth and diversity of life on a coral reef. Fishes are the most recognizable inhabitants, however, they represent only a fraction of all reef animals. Sponges grow in bizarre shapes, often resembling vases or organ pipes; anemones and feather stars extend scores of tentacles like delicate flowers; soft corals imitate bushes waving in a breeze. Even the rocklike reef-building corals are actually colonies of thousands of individual animals. And that’s not to mention the cryptic crabs, undulating sea snails and spiraled Christmas tree worms.

What most nondivers don’t realize is that there is plenty of life in non-tropical environments as well. The temperate waters along both coasts of North America support many times more life than warm seas. The nutrient-rich waters are thick with the microscopic creatures that form the basis of the entire food chain. Kelp forests are nature’s underwater jungle, and the chilly Pacific Northwest is home to the massive Metridium anemone and the gentle giant octopus.

While freshwater diving venues don’t support the diversity of life found in the oceans, the fish population can be impressive, especially where they’ve been nurtured. Whether it’s migratory salmon, intrusive bluegill or the elusive paddlefish, there is bound to be something to entertain divers. Also, by concentrating your gaze in a small area, you’ll find a variety of snails, plants and other attention-getters right at the tip of your nose.

Living creatures are not the only underwater attractions for divers. Man-made features are also popular. The Great Lakes and the entire East Coast of the United States are known for shipwrecks, many sunk during World War II. Realizing the potential for tourism, more and more communities are cleaning, preparing and sinking wrecks — commercial jets as well as mothballed ships — strictly for the pleasure of scuba divers. And lakes formed by damming rivers often hold the remains of flooded villages and drowned forests.

Nondivers often believe that it is dark underwater. Certainly this is not the case in most warm-water areas, where visibility commonly exceeds 100 feet (30 m). Water does absorb and scatter sunlight; reds are the first to disappear, turning underwater scenes to shades of blue, or in areas with extensive suspended particles, to emerald green. Many divers routinely carry lights — both to restore natural colors and to peek under shaded overhangs.

Although there are plenty of interesting and unusual sights to hold the attention of scuba divers, some enthusiasts dive for the sheer pleasure of floating weightless in an environment as close to outer space as the majority of us will ever experice.

Aren’t you afraid of sharks?

Of the almost 400 species of sharks inhabiting our oceans, only a handful are known to be aggressive toward man; none of these are typically encountered by divers. Despite their position at the top of the ocean’s food chain, sharks’ reaction to a diver’s presence in their domain is commonly one of disinterest. Half of shark attacks are to surfers, whose appearance on the water’s surface approximates that of seals or sea lions, a major food source for some species.

The “Jaws” movies were largely responsible for the image of sharks as man-eating killing machines, and the media attention surrounding last year’s shark attacks in U.S. waters unfortunately reinforced that impression. The truth is that only 76 unprovoked shark attacks occurred worldwide in 2001, five of them fatal. Just 11 of the attacks, all nonlethal, involved divers or snorkelers. In other words, your chances of getting injured by a shark while scuba diving are minute.

Many scuba divers actually seek out shark encounters. The Galapagos Islands of Ecuador, Cocos Island off Costa Rica and the Flower Garden Banks in the Gulf of Mexico are popular destinations for diving with schooling hammerheads. A few dive operators offer open-ocean encounters with more aggressive shark species in the relatively safe confines of a shark cage.

Diving venues around the world routinely engage in shark-feeding dives, in which guides hand-feed reef sharks or anchor giant “chumsicles” — frozen balls of fish — near the bottom, as fascinated divers watch from a respectful distance. Although the wisdom of such activities has recently been called into question, these thrilling dives have been increasingly popular in places like the Bahamas. No injuries to participants have been reported in several years of shark feeding, and the educational value of observing sharks up close helps spread the truth: Sharks are an indispensable part of the ocean’s natural balance.

The fact is that sharks are in far more danger from humans than we are from them. It is estimated that up to 100 million sharks are killed each year as bycatch to commercial fishing activities as well as for disproven medicinal remedies and shark fin soup. Several species are actually in danger of becoming extinct — an eventuality that would have serious, irreversible ecological consequences.

Why do you need to wear weights?

Believe it or not, the human body is quite buoyant. With your lungs full of air, you’d be hard pressed to sink, especially in salt water. That’s why most people have no trouble snorkeling — when you lie flat on the surface with your head in the water, your weight is easily supported, whether you weigh 100 pounds or 300 (45 kg or 136).

Add scuba equipment and you become even more buoyant. Even though scuba tanks will sink when full, divers wear buoyancy compensators (BCs), vests that not only secure the tank to the diver’s back but also contain inflatable air bladders to provide flotation on the surface. Wetsuits are made of neoprene, a type of rubber that contains thousands of tiny air pockets. These air cells provide insulation to prevent heat loss and in addition add considerable buoyancy.

Even with all the air vented from a BC, a diver usually cannot sink without weights. Lead can be strung in blocks on an easily ditchable weight belt worn around the waist or bagged as tiny beads in a removable weight pouch. Divers strive to wear as little weight as necessary to allow them to descend from the surface without struggling, and remain slightly negatively buoyant throughout the dive. (Divers add a small amount of air to their BC while underwater to maintain neutral buoyancy while at depth.)

The amount of weight worn varies from a couple of pounds (1 kg) to more than 30 pounds (14 kg) depending on a variety of factors. Salt water, for instance, is more buoyant than fresh water, so about 2.5 percent more weight is required. The type of exposure protection worn, specific scuba equipment, dive conditions and an individual’s body composition also affect the optimum amount of weight. Divers regularly re-evaluate the amount and placement of their weighting system.

How deep do you go?

The industry standard depth limit for recreational divers is 130 feet (39 m) at sea level. During the basic scuba certification, students experience depths of 30-60 feet (9-18 m), and a “deep” dive is considered more than 60 feet (18 m).

“Going deep” is not an end in itself for scuba enthusiasts. Science has shown that the vast majority of marine species live at depths less than 60 feet (18 m). Within the limits of their training, divers go as deep as necessary to see the points of interest at a particular dive site. That may mean 110 feet (33 m) along a coral-covered wall, 90 feet (27 m) on a wreck or 20 feet (6 m) in a river.

Staying shallow holds several advantages. One is that your air lasts longer. The deeper you go, the greater the water pressure. The scuba regulator works by automatically providing the diver air at the same pressure as the surrounding water. Therefore, the air in the cylinder is used faster the deeper the dive. For example, at 100 feet (30 m), air is used four times as fast as at the surface. If it takes a diver an hour to become low on air at or near the surface, all else being equal, it would take the same diver only 15 minutes to deplete his air on a 100-foot dive.

Another advantage of remaining shallow is that the diver’s body accumulates less nitrogen in a given amount of time. This allows him to stay down longer without needing to make a mandatory decompression stop. Decompression diving is beyond the scope of standard recreational dive training.

Recreational divers primarily breathe filtered air compressed into the scuba cylinder. Nitrogen, which comprises 79 percent of “plain old” air, is not metabolized, but accumulates in the tissues when breathed under increased pressure as you dive. This is what causes decompression sickness, or the bends; when the absorbed nitrogen is released too quickly, it forms bubbles in the tissues. The same percentages as above apply: A diver absorbs nitrogen four times faster at 100 feet than at the surface. There is a definite trade-off between how deep you go and how long you can stay down.

Some recreational divers expand their skill range through additional training in technical diving disciplines. These include courses in deep diving and use of mixed breathing gases — gases other than plain old air.

Are my kids too young? Am I too old?

Scuba diving is a nondiscriminatory activity. Anyone with the physical ability to handle the equipment and the emotional maturity to comprehend the rules and take responsibility for his or her safety and that of his dive buddy, can scuba dive safely and enjoyably.

There is no upper age limit on learning scuba. Prospective scuba students are asked to have a standard medical questionnaire completed by a doctor — preferably one knowledgeable in hyperbaric, i.e., pressure-related, medicine. Certain conditions may preclude those of any age from diving, temporarily or permanently, especially conditions associated with lung functions or anything that may impair your ability to perform effectively underwater. As long as you maintain relatively good physical and mental conditioning, it’s never too late to learn scuba. Many divers continue into their 70s and 80s.

Minimum age restrictions do apply, although these have recently been lowered by some scuba certification agencies with the development of noncertification programs for children as young as 8 years old. These programs allow enthusiastic kids to get a taste of scuba diving under strict supervision and depths not exceeding about 6 feet (2 m).

In general, children must be 10-12 years old, depending on the agency, to be certified as “Junior” divers, who may dive only under restricted conditions (i.e., limited depths and supervision by a scuba professional or certified adult diver). At 15 or 16 years old, students receive the same certification as adult divers. Of course, children mature at varying rates and only parents can decide whether their child is emotionally and physically ready to shoulder the responsibility inherent in scuba diving.

Handicapped individuals can also participate in diving activities with the help of specially trained buddies.

How do I get certified? How long does it take?

All scuba instructors are affiliated with one or more of several scuba training agencies that operate in North America and worldwide; each with its own curriculum designed according to the training philosophy of its governing body. Despite this diversity, the industry has responded to the need for cross-agency consistency by implementing a set of minimum standards for the basic level of scuba certification.

Therefore, at least at the entry level, what you are taught is similar, no matter which agency you certify through. Agencies allow their instructors sufficient leeway to incorporate additional material specific to local dive conditions as is necessary to produce competent divers. Local scuba centers are often associated with one or more scuba training agencies to assure their customers maximum flexibility in learning opportunities.

Find a dive center near you –>

The basic scuba certification course, commonly called Open Water Diver, is divided into three sections: academics, confined water and open water. The academics portion develops the knowledge base necessary to understand the principles behind diving rules and procedures. Traditionally, this involved several classroom sessions spread over days or weeks, but with the advent of interactive computer technology, a combination of self-paced lessons and/or amplification and testing by a scuba instructor has allowed academic training to fit just about anyone’s busy schedule.

You practice dive procedures and learn to use the equipment in the confined water section, usually consisting of several instructor-led sessions in a pool. The open-water section consists of four or more supervised dives, during which you’ll demonstrate your mastery of scuba skills in an actual dive setting. When you earn your certification card you’ll be qualified to dive in conditions similar to those in which you were trained.

Open Water certification can take anywhere from three days to a year to complete, depending on your preference and schedule. Your local dive center may offer a variety of training options, mixing classroom and home-based computer training with pool sessions and local open-water checkout dives. Another option for those in cold-water areas, especially in the winter, is to complete the first two sections and then accompany your dive center on a trip to a warm-water dive destination to complete the open-water portion. Still another possibility, after completing the academic and confined water sections, is to request referral papers, which allow you up to a year to complete the open-water dives with a qualified referral instructor at a resort location.

Dive centers want to make scuba certification work for you. Some offer two-weekend “executive” courses, and many resort areas offer a three-day intensive certification for those on vacation. These latter options are most appropriate for those with good water skills and the willingness and ability to assimilate the material quickly.

Isn’t it expensive?

Costs for scuba diving compare favorably with those inherent in other active recreational pursuits.

Pricing for Open Water scuba training varies widely according to the local market, but should include the cost of training materials. Use of scuba equipment for the duration of the course, other than mask, snorkel and fins, which are considered personal and supplied by the individual, may also be included.

Once certified, scuba diving can cost as little as renting a scuba tank or having your own filled — an expense characteristically less than $10 per tank — and traveling to an area lake, quarry or river, or diving from a public beach entry. Compare this with the price of lift tickets at ski resorts, or a round of golf.

One thing that these activities have in common is the need for equipment. Purchasing a set of scuba gear — BC, regulator, exposure protection — is no more expensive than getting started in skiing or golf. For the infrequent diver, renting equipment may be an attractive alternative. Of course, as in all worthwhile pursuits, you may choose to expand your scuba “must have” list with items such as a dive computer, underwater camera and other accessories.

Similarly, scuba vacations are available to suit every budget, from weekends in bunkhouse accommodations with shore diving, to luxury dive resorts in exotic locations. The price of airfare is a major factor in considering vacations to any faraway destination, whether it’s for sightseeing or diving, or a combination of both. Live-aboard dive boats offer the opportunity to visit remote dive destinations and do as much diving as you desire for an all-inclusive price.

Do I need to renew my certification periodically?

Recreational scuba certifications do not have to be renewed periodically; they are good for life. A certification card is required in order to rent scuba tanks or have tanks filled, and also when renting gear or booking space on a dive boat.

However, many dive operators also require proof that the individual has been diving within the past six months or a year. A logbook showing completed dives within the required time frame is usually adequate proof. Lacking such documentation, the operator may require a checkout dive with a scuba instructor to verify that your skills are sufficiently current to dive safely without supervision.

Like any skill, scuba training will become rusty if not used for long periods. It is wise to take a refresher course, offered by all dive stores, after a hiatus from diving. Even after an interval of several months or when using different equipment, it is highly recommended to schedule time in a pool to practice basic scuba skills and re-familiarize yourself with the equipment.

The best way to maintain scuba skills is to dive regularly and continue training. Scuba proficiency is a continuum — you can’t learn it all in one basic course. Dive centers offer a whole range of courses to improve your skills and comfort level underwater, as well as specialty courses to expand your horizons. You can learn additional navigation techniques, how to identify the fantastic creatures you’ll see, the excitement of diving at night, the intricacies of capturing all of it in still photos or video, and much more.

If you are interested in assisting other divers or teaching scuba yourself, a variety of leadership courses will turn you into a scuba professional. The possibilities for a lifetime of enjoyable diving are practically endless. You just have to get started.

By Linda Lee Walden

Scuba Diving and Coronary Artery Disease

Howard Ratsch — Sun, 21 Feb 2021 12:25:50 GMT

Educational Blog

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Scuba Diving and Coronary Artery Disease - Advanced Diver Magazine

By Dr. Douglas Ebersole, he is a cardiologist specializing in coronary and structural heart interventions at the Watson Clinic LLP in Lakeland, Florida. He is also an avid technical, cave, and rebreather diver and instructor. He can be reached at debersole@watsonclinic.com.

It is estimated that there are about 3 million certified scuba divers in the United States. A large number of these individuals are middle-aged or older and at risk for coronary artery disease. Cardiovascular disease is the third most common cause of death while diving and remains the principal cause of death in the general population. The development of symptoms of angina, pulmonary edema, or sudden cardiac death underwater carries with it a much higher mortality than would the same event on land. This article will review the workloads related to scuba diving, ways to assess risk in those with or at risk of developing coronary artery disease, and make recommendations to make scuba diving safer.

Scope of the Problem
In 2008, Denoble published a paper showing the annual death rate for scuba divers was 16.4 per 100,000 persons (1). This was similar to the rate of 13 jogger deaths per 100,000 participants each year (2) or the risk of driving where motor vehicle accidents result in 16 deaths per 100,000 persons per year (3). Thus, while the likelihood of dying scuba diving is quite small, understanding how and why these deaths occur is imperative. Unfortunately, the ultimate cause of death while scuba diving is drowning, This does not give us a great insight into what led to the drowning. Denoble reported on the causative process of 947 fatalities in an attempt to better define scuba diving fatalities (4). He divided this into sequential components: trigger, disabling agent, disabling injury, and cause of death. Cardiac events constituted 26% of disabling injuries and these events were frequently associated with a history of cardiovascular disease and age greater than 40 years. Thus, it looks like underlying cardiovascular disease is a major component in scuba diving deaths.

Workloads Associated with Scuba Diving
It is clear that exercise itself is a cardiovascular stress and that the majority of non-traumatic deaths during exercise are cardiac in origin. In most situations, diving is not particularly physically stressful. However, there are times that due to current, waves, wind and other environmental stressors that demands during diving can reach 20 ml/kg/min (6-7 METS). Exercise capacity is reported in terms of estimated metabolic equivalents of task (METs). The MET unit reflects the resting volume oxygen consumption per minute (VO2) for a 70-kg, 40-year-old man, with 1 MET equivalent to 3.5 mL/min/kg of body weight.

In the standard Bruce protocol, the starting point (ie, stage 1) is 1.7 mph at a 10% grade (5 METs). Stage 2 is 2.5 mph at a 12% grade (7 METs). Stage 3 is 3.4 mph at a 14% grade (9 METs)n and Stage 4 is 4.2 mph at 16% grade (12 METs). This protocol includes 3-minute periods to allow achievement of a steady state before workload is increased.

Thus, a diver with a steady state exercise capacity of 6-7 METS can expect to manage most diving contingencies without concern for cardiovascular complications. In most occupational exposures requiring increased physical activity, guidelines recommend maintaining workloads below 50% of maximal oxygen consumption. Based on this relationship, a diver who is expected to minimize safety concerns related to environmental contingencies should have a maximum oxygen consumption of 12-13 METS – or about 12 minutes on a standard Bruce protocol exercise test. Divers with peak exercise capacity below that level could expect to dive safely in low stress conditions such as warm water, minimal currents, and calm seas but could develop cardiovascular limitations under stressful diving conditions.

Who is at risk?
For divers older than 35 years, the dominant risk for sudden death is from coronary artery disease. Although the incidence of coronary artery disease death is falling, the rising incidence with age makes this diagnosis the most important consideration when clearing divers who are middle-aged or above.

One strategy to lower the risk of cardiovascular deaths would be to screen all adult participants prior to certification as most exercise-related cardiac events in adults are due to atherosclerotic cardiovascular disease.

The Framingham Risk Score is one of a number of scoring systems used to determine an individual's chances of developing cardiovascular disease. A number of these scoring systems are available online (5,6). Cardiovascular risk scoring systems give an estimate of the probability that a person will develop cardiovascular disease within a specified amount of time, usually 10 to 30 years. Because they give an indication of the risk of developing cardiovascular disease, they also indicate who is most likely to benefit from prevention. For this reason, cardiovascular risk scores are used to determine who should be offered preventive drugs such as drugs to lower blood pressure and drugs to lower cholesterol levels.

The population risk for divers could be predicted by using tools such as the Framingham Risk Score and potential participants with a specific score could be identified and excluded. The problem with this approach is that atherosclerotic cardiovascular disease is prevalent among lower-risk subjects. Also, extremely high-risk subjects are only a small part of the total population. Consequently, the largest absolute number of acute events occurs not in the highest-risk subjects, but in the moderate- and lower-risk groups. Excluding the highest-risk group likely have little effect on the total number of deaths.

A Framingham risk score lower than 10% ( less than 1% per year risk) is considered a low score. If a subject is assessed to be at low risk in general, that individual is not likely to have an acute coronary event while diving. On the other hand, high-risk individuals (Framingham score > 20%) could be at considerable risk and should have further evaluation to evaluate whether diving will be safe. Intermediate-risk individuals with a Framingham score between 10% and 20% should have further risk stratification to assess their risk for an acute coronary event while diving.

In all individuals, regardless of risk, we should practice primary prevention of coronary artery disease. The recommended performance measures for primary prevention are:

1.	Lifestyle/risk factor screening

2.	Dietary intake counseling

3.	Diabetes screening and management

4.	Physical activity counseling

5.	Smoking/tobacco cessation

6.	Weight management

7.	Blood pressure control

8.	Blood lipid measurement and control

9.	Global risk estimation with tools such as Framingham Risk Score

10.	Aspirin use in selected individuals

Implementation of these measures requires performance of a careful history and physical examination, laboratory testing for lipids, and formal assessment of cardiovascular risk.

Performing stress testing in selected individuals, such as those with intermediate or high-risk Framingham score, is also an approach. In comparison to younger individuals, far less attention has been paid to designing screening programs for older, usually recreational, athletes. Few detailed pre-participation guidelines exist, and there is little reported experience in this age group. Instead, most authorities focus on strategies used in clinical medicine for the early detection of atherosclerotic diseases, as these are the most common cause of death in this age group.

Since most individuals are asymptomatic, the history is often more helpful in identifying risk factors rather than symptoms. Similarly, there may be few detectable abnormalities at rest or even with exercise as events are often due to spontaneous rupture of non-obstructive plaque.

The American Heart Association issued recommendations for preparticipation screen in older athletes in 2007 (7). This document recommends that older competitive athletes (>35 to 40 years) be “knowledgeable” regarding their personal history of coronary artery disease risk factors and family history of premature coronary artery disease. Further, stress testing should be preformed selectively for individuals engaging in vigorous training and competitive sports, and who meet the following criteria: men > 40 years or women > 55 years with diabetes mellitus, or at least two risk factors or one severe risk factor other than age. Finally, the document recommends education regarding prodromal cardiac symptoms, such as exertional chest pain.

What about patients with established coronary artery disease?
Patients with known coronary disease often have been subject to revascularization either by coronary artery bypass surgery or by percutaneous coronary intervention, usually with implantation of one or more coronary artery stents. The degree of revascularization can determine safety in diving. With complete revascularization, low-stress diving can be accomplished successfully, but diving in rough seas, fast currents or cold water could be risky. There are many divers who have returned to diving after either coronary artery bypass surgery or stenting. Success in return to diving is based on restored exercise capacity without ischemia after revascularization and choosing diving environments that do not produce excess stress on the cardiovascular system.

Patients with significant reduction in left ventricular systolic function (LVEF < 35%) are at risk for exacerbation of congestive heart failure while diving. Water immersion itself results in approximately 700 cc of fluid shift into the central circulation. This could provoke congestive heart failure in patients with impaired left ventricular systolic function. Additionally, most patient with LVEF < 30-35% will have impaired exercise tolerance when diving as outlined above. For these reasons, patients with significant left ventricular systolic dysfunction should be advised against scuba diving.

Recommendations

1.	All adults should be evaluated for their risk of coronary artery disease prior to scuba diving

2.	Selected individuals with intermediate to high-risk Framingham scores should be referred for additional evaluation, such as treadmill testing prior to scuba diving.

All individuals should practice primary prevention strategies to decrease their risk for the development of coronary artery disease

Smoking cessation
Blood pressure screening and management
Weight control
Physical activity counseling
Cholesterol screening and management
Diabetes mellitus screening and management

Patient with coronary artery disease may begin (or return to) diving as long as they have been revascularized with no ischemia on treadmill stress testing, have good exercise tolerance (defined as a maximum exercise capacity of 13 METs or an ability to sustain a workload of 6 METs), and have relatively preserved left ventricular systolic function.

Education Blog: 5-Year Trends in The Dive Industry

Howard Ratsch — Fri, 22 Jan 2021 14:30:20 GMT

Educational Blog

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

5-Year Trends in The Dive Industry: Scuba Gear, Dive Travel & Certifications | by Darcy Kieran | Scubanomics | Oct, 2020 | Medium

DEMA recently published the results of its 2020 ‘Dive Behavioral Research Project’ from a survey conducted in 2019. A previous dive behavioral research was conducted in 2014.

We have reviewed the results of both the 2019 and the 2014 studies to identify key pieces of information to help you manage your dive business. We are especially interested in changes between these 2 reports to identify trends in the scuba diving industry.

About DEMA’s Dive Behavioral Research Project

The goal of the project to analyze and understand the demographics and psychographics of scuba divers as it pertains to dive travel, scuba diving equipment purchases, and scuba courses.

DEMA is the Diving Equipment & Marketing Association commonly referred to as our dive industry trade association.

The data collection for the DEMA Dive Behavioral Research Project was done through an online survey.

In 2014, 24000 divers responded to the survey with more than 2000 from Canada, about 13000 from the USA, and the remainder from countries across the planet.

In 2019, only 9700 scuba divers responded to the survey with about 1000 from Canada, almost 5000 from the USA, and the rest from countries around the globe.

Available Data Sets and Reports from The Dive Behavioral Research Project

So far, DEMA released 2 sets of data from the 2019 survey:

· 2020 results from all responding countries

· 2020 results from USA participants

A Canadian report is forthcoming.

Shortcomings of DEMA’s Reports on Scuba Diver Demographics and Psychographics

There is a serious issue with the 2019 survey besides the fact that the data set was significantly smaller (about 9000 respondents vs. 14000 in 2014).

In the 2019 survey, more than 40% of the respondents were dive professionals: divemasters, assistant instructors, and scuba diving instructors. If we are interested in understanding the behavior of ‘scuba divers’, the 2019 data set is highly unreliable as almost half of the respondents were scuba diving professionals.

We know dive professionals have a behavior that can be significantly different than that of the average Joe Diver. For instance, typically, scuba instructors dive more frequently and purchase more dive gear.

Furthermore, when comparing the two sets of data (2014 vs 2019), we are facing a double problem in regards to dive professionals. In the 2014 study, less than 10% of the respondents were scuba diving professionals (divemaster and up) while there were more than 40% in the 2019 survey

Therefore, we are facing the following 2 serious issues with this DEMA study on scuba diver demographics and psychographics:

· We can’t use the results to understand the behavior of a ‘scuba diver’ as both reports include dive professionals that are much more committed to scuba diving than the average scuba diver — which is especially true in the 2019 set of data with more than 40% of the respondents being dive professionals.

· We can’t fully rely on trends identified in changes from 2014 to 2019 since we would be comparing oranges to electric cars.

It is fair to assume that dive professionals are more ‘core’ divers than ‘casual’. In fact, we see that the average number of dives completed by 2019 respondents is higher than it was in the 2014 study. Learn more about core and casual divers on Scubanomics.

We’ve contacted DEMA to request a version of both reports (2014 and 2019) excluding all dive professionals, so we can better understand the behavior of scuba divers in regards to dive travel, scuba gear, and dive certification courses. Tom Ingram, head of DEMA, assured us that they “have plans for additional segmentation of the consumer data, including based on certification levels”.

We hope DEMA will quickly produce 2014 and 2019 reports excluding dive professionals as this would be highly valuable to its members trying to understand the behavior of scuba divers.

In the meantime, let’s see what information we can extract from the currently available reports mixing scuba divers and dive professionals.

Key Scuba Diver Demographics and Psychographics 2014 vs 2019

Two interesting trends identified in our review of these 2 studies relate to eLearning and rebreathers.

Scuba Diving Certification Courses at Home, in a Resort, and via eLearning

An assumption often discussed in the dive industry is that online learning is hurting local dive centers because it becomes easier to bypass the local dive center by completing the ‘theory’ part of the course and then flying to an exotic dive destination to complete the ‘pool’ and ‘open water’ parts of the scuba diving certification course.

This appears to be partially true but not as major as we usually assume it to be.

· The number of scuba divers who have completed the ‘theory’ part of the course online with no interaction with a local dive shop before flying to a dive resort to complete the ‘pool’ and ‘open water’ parts of the course has increased by less than 1%: from 6% to 6.89%

Meanwhile, we observe more significant changes in the following modes of completing the entry-level open water diver certification:

· The number of scuba divers who have completed all parts of the scuba course while in a vacation setting has declined from 23.9% to 18.7%.

· The number of scuba divers who have completed the ‘theory’ and ‘pool’ parts of the course before going on a trip has increased from 14.6% to 17.6%.

Therefore, it appears there is no reason to fear that eLearning is encouraging scuba divers to bypass the local dive shop. On the contrary, eLearning seems to have increased the number of people completing the ‘pool’ part of the course at home before going on a trip.

It may be more accurate to assume that the online high visibility of eLearning is actually encouraging people to find a local dive shop to complete their pool sessions locally. It’s reducing the number of people going straight to a dive resort to complete the entirety of the entry-level open water certification course.

Increased Interest for Rebreather, Sidemount, and Freediving

There is a huge shift between 2014 and 2019 on the next courses respondents were most interested in taking.

In 2014, the courses in which respondents were most interested in taking next were rescue diver, wreck diver, divemaster, and underwater photographer. This significantly changed in the 2019 survey.

Not only the list of courses has changed but the level of interest has skyrocketed.

We must urge caution with these numbers. As mentioned earlier, the 2019 sample included more than 40% of dive professionals who are much more committed to scuba diving than the average Joe Diver.

Typically, scuba diving instructors have been a good target market for tech diving as they are looking for more challenges after reaching the pinnacle of recreational diving. Therefore, it is unlikely that there is an 84% interest in rebreathers in the general population of scuba divers.

However, these numbers do indicate a significant increase in interest toward tech diving (rebreather, side-mount, other mixed gas) and freediving.

Freediving has seen steady growth over the last few years. Dive gear manufacturers carrying freediving equipment have reported growth in their freediving line of products even when scuba gear sales were down. Both Mares and Aqualung have made significant investments in developing their freediving line of products.

It appears freediving is appealing to the newer generations. It is challenging without requiring you to carry all the cumbersome equipment required for scuba diving. It also makes for great Instagram look-how-cool-I-am pictures!

Role of The Scuba Diving Instructor

The most significant information source for scuba divers to decide what they want to do next remains the dive instructor and divemaster. Instructor/Divemaster gets a score of 4 on 5 while the local dive shop gets a 2.9.

As we’ve stated before, there is a continued need for local scuba diving activities but the focus should be on the action of scuba diving, not on trying to sell dive gear in an understock retail store. We believe that in the years to come, the role of local dive instructors will become more significant while local dive shops redefine their mission and business model.

What’s Next?

Once DEMA releases the 2014 and 2019 survey results for ‘scuba divers’, excluding dive professionals, we will be able to get more valuable information out of these reports.

Subscribe to Scubanomics to be informed when this data becomes available.

Don’t be left out: Subscribe to be the first to know about dive industry news and market data.

Continue reading: Scubanomics Table of Content.

Connect, to be our dive business buddy: LinkedIn | Twitter | Facebook

Sign up for Scubanomics: Scuba Diving Industry 2021

What Is A Pulse Oximeter?

Howard Ratsch — Sun, 20 Dec 2020 13:13:09 GMT

Educational Blog

Coronavirus FAQs: What Is A Pulse Oximeter? Why Are So Many People Buying One? : Goats and Soda : NPR

by LAUREL WAMSLEY

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

FROM NPR

Each week we answer some of your pressing questions about the coronavirus and how to stay safe. Email us your questions at goatsandsoda@npr.org with the subject line: "Weekly Coronavirus Questions." This week, we're considering questions about pulse oximeters.

As the coronavirus continues to spread, a small medical device called a pulse oximeter has started to fly off the shelves. In fact, demand has spiked to such an extraordinary degree that you may not be able to buy one right now in your local pharmacy or online.

What is the value of the device during this pandemic? Do you need to have one at home? The first question is relatively easy to answer. The second is a little more complicated.

What is it?

A pulse oximeter is a small electronic device that estimates the saturation of oxygen in your blood. You want a number in the 95% to 100% range. If the number drops to 92% or lower, that's a cause for concern. That's generally the level where a doctor might put you on supplementary oxygen and keep you in the hospital for observation.

To come up with that percentage, the device clamps onto your finger or earlobe and shoots different wavelengths of light through the small capillaries, explains Dr. Richard Levitan, a New Hampshire-based emergency room physician who specializes in airway management. (For a more thorough scientific explanation, read this.)

The term for low blood oxygen levels is hypoxemia. In this condition, your body's organs may not work right. Severe cases can interfere with heart or brain function.

You've likely had your blood oxygen monitored by a pulse oximeter already. It's used during some physical exams and is considered essential during operations and intensive care. The devices also give your heart rate.

Why are these devices suddenly getting so much attention?

COVID-19 can bring on what's called COVID pneumonia — an infection in which the lung's air sacs fill with fluid or pus. And it's possible that someone infected with the novel coronavirus might be in the early stages of COVID pneumonia – including a drop in blood oxygen level — without experiencing any difficulty breathing.

In such cases, a pulse oximeter might signal that you're in trouble before you realize it. That's what Levitan saw when he spent 10 days working in the ER at Bellevue Hospital in New York City earlier this month: Many COVID patients were already very sick with COVID pneumonia by the time they arrived. They were breathing rapidly, their blood oxygen levels dangerously low. Like mountain climbers, the patients had grown accustomed to gradually decreasing levels of oxygen and didn't realize they were in distress.

Many of them said they only recently started feeling short of breath though they had experienced symptoms of COVID-19 for days. By the time the patients went to the hospital, says Levitan, the virus had already damaged their lungs, and many were in critical condition. He saw COVID pneumonia patients with oxygen saturation levels as low as 50 percent.

"These COVID patients have adapted to this slow, insidious drop in their oxygen and they don't know it," he told NPR. "Then when they come in with shortness of breath, it is late in the process." In his opinion, a pulse oximeter could have caught the warning sign of low blood oxygen level earlier on.

The disease "kills by silently causing [a decrease in] oxygen. When you come in late in the disease, which is basically everybody who we now have coming to the E.R., there is a high mortality," he says.

Levitan says that in medicine, earlier treatment leads to better results — "and that's true of COVID, as well."

Should you get one?

Levitan thinks that in the midst of a respiratory pandemic, it makes sense to have a pulse oximeter at home – just as you might have a thermometer to track fevers. If you have symptoms of COVID-19, he says, like weakness, muscle aches or fever, you could use the device to measure blood oxygen levels.

That 92% figure (or lower) is a sign that "you should get evaluated because this disease kills silently and you don't have to have significant shortness of breath" to be at risk. (Although people at high altitudes might have levels "in the low 90s and be fine," he adds.)

Dr. Elissa Perkins, a professor of emergency medicine at Boston Medical Center, doesn't necessarily think everyone needs to buy a pulse oximeter. She worries that people will depend on the device's reading rather than calling a doctor if they're feeling sick.

"I think it's a bit of a stretch to say that people should all have these at home," says Perkins, though she understands why people would want them.

"In general, I think honestly, if people are starting to feel symptoms or feel even a little bit short of breath, they should probably contact their physician, if possible," she says. "Most places or many places at this point are offering telemedicine visits, telehealth visits and that can give a more thorough picture of what somebody is experiencing than just one number on a pulse oximeter."

But she's not completely opposed to home pulse oximeters. She says if you have symptoms consistent with the novel coronavirus, using a pulse oximeter and consulting with a doctor can be a good strategy.

She is concerned about one risk: People could be falsely reassured by good numbers into thinking they're not very sick. People with COVID "can get incredibly dehydrated, people can get very weak," says Perkins. "We've seen people fainting or passing out, who don't have particular respiratory symptoms and don't have shortness of breath. So it's another piece of data, but it's certainly not the only piece of data."

There are other concerns. The reading can be less accurate if a person is wearing nail polish or artificial nails, has cold hands or poor circulation.

It's possible to accidentally read the numbers upside down and panic over a seemingly eye-popping number. Or the device itself could be inaccurate.

The American Lung Association chief medical officer Albert Rizzo issued a statement on Thursday advising against "buying pulse oximeters unnecessarily."

"[U]nless you have a chronic lung or heart condition that affects your oxygen saturation level on a regular basis, most individuals do not need to have a pulse oximeter in their home," Rizzo said. "Most importantly, if you're interested in purchasing a pulse oximeter for home use, please discuss the necessity and use of the device with your health-care provider. A medical professional can determine if it would be helpful and also provide direction for interpreting the readings in the context of how you are feeling. Your pulse oximeter reading should be used along with your other symptoms such as shortness of breath, fever, fatigue, as parameters that would prompt a call to your doctor."

Abraar Karan, internal medicine doctor at the Brigham and Women's Hospital and Harvard Medical School, is a proponent of caution as well when it comes to pulse oximeters for home use. He says it remains to be seen how predictive low oxygen levels are at correctly identifying patients who will have a severe course with the disease. He points to a recent study looking at 5,700 patients hospitalized with COVID-19 in New York City, which found only 27.8% needed supplemental oxygen at triage.

And he shares Perkins' concern about people being either falsely comforted or unnecessarily alarmed.

"What we don't want to happen is that people are in real distress but think that because their home pulse oximeter reads normal, that they are fine," Karan writes via email. "We also need to make sure that patients are using the pulse oximeter properly and that it is reading correctly — otherwise, you could have more people coming to the emergency room that may not need to be there."

But Levitan says that kind of strain on ERs already happens when people interpret home blood pressure monitors or thermometers incorrectly. A much bigger concern, Levitan says, is people dying suddenly from COVID. And he doesn't worry that the device will just make people more anxious: "You know what? We've got fear. We've got anxiety. We need reassurance."

Where do I buy one — and how worried should I be if there's a delay in getting it?

If you do think a pulse oximeter would be valuable, Levitan suggests buying one from a medical source like a pharmacy rather than a random site on the internet – and it's a good idea to look for one that's been FDA-approved, if possible. You can go to the FDA's 510(k) Premarket Notification page here and search for "oximeter."

It's possible to buy devices that haven't been approved for medical use, and such devices may be less accurate.

Just a few months ago, it would have been easy to find consumer models costing about $30 typically on pharmacy shelves. They are often used by people with chronic lung disease who are taking supplemental oxygen to make sure they were getting the right amount of oxygen.

With many pharmacies sold out, people are turning to sites like eBay and Amazon, where devices can be found in the $60 range.

But Levitan says you shouldn't fret if you have to wait a few weeks to get one: "You know what? We have 12 to 24 months of this [coronavirus]," he predicts.

He says in an age of respiratory pandemics, there is very useful health monitoring that people can do form home, in concert with a phone call to a medical professional.

"We need to change the public perception of what health monitoring means in this age of respiratory pandemics," he says. "When you combine heart rate measurement, oxygen saturation and temperature, which are all three things you can do at home — and especially if you combine it with a phone call to your doctor or to your local emergency department ... that's incredibly informative."

New Business Model

Howard Ratsch — Wed, 21 Oct 2020 11:08:58 GMT

Educational Blog

A New Business Model for a Redefined Local Dive Center

COVID-19 accelerated changes happening in the scuba diving industry. How to be ready.

By Darcy Kieran

https://medium.com/scubanomics/a-new-business-model-for-a-redefined-local-dive-center-12b9c24ac3f5

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

Retail, education, and travel industries are going through a severe transformation that started before the coronavirus pandemic. But the speed of change has accelerated in a COVID-19 world, and we need to keep up — or better yet, get ahead of the curve. The dive industry has been resisting changes to its business model for a while but can no longer withstand a tsunami of changing customers’ expectations and behavior.The global pandemic has reset the gameboard. How can dive businesses emerge stronger?

I will look at the historical ‘distribution channel’ used to provide scuba diving lessons, dive gear, and scuba diving travel to scuba diving consumers. Then, I’ll look at how it is changing and how the current coronavirus pandemic is accelerating this evolution. Finally, I’ll look at what it means for your scuba diving business.

Traditional Distribution Process for Scuba Diving Products & Services

Historically, dive gear and scuba lessons have been provided to the consumer by ‘local dive shops’ (in ‘origin’ dive centers) and ‘dive resorts’ (in dive destinations). And way back then, dive travel was mainly sold by local dive shops.

We’re talking, here, pre-internet. But the dive industry business model barely changed after the arrival of the internet. Consumers have changed, but not the scuba diving industry.

Bear with me for a minute.

Pre-internet, it was difficult for a newly certified scuba diver to independently select the best dive destinations for his/her annual vacations. The dive instructor in the local dive shop was the principal source of information. Scuba divers would come to the local dive center to check pictures of previous trips to different scuba diving destinations. And group travel was arranged by the dive instructor.

Dive gear manufacturers, scuba diving training agencies, and dive resorts (dive destinations) were relying on local dive shops to reach consumers.

The local dive shop was both ‘the front line’ and the gatekeeper.

This model doesn’t work anymore, and you can expect this fact to be even more apparent post-COVID19.

Noticeable Dive Industry Trends

I will be looking at ‘trends’ but only as it relates to the distribution channels used to reach scuba diving consumers.

Trends in Dive Travel

Dive travel was the first scuba diving industry sector to bypass the local dive shop significantly. Knowledge about dive destinations is now available to all, on the internet — with much more in-depth knowledge than what the local dive instructor could provide.

A local dive professional can’t be knowledgeable about every dive destinations in the world. In that sense, the internet is providing more value to the scuba diver. And ‘providing value’ is vital for a business to be sustainable.

The next dive industry segment to bypass the local dive shop (in ‘origin’ locations) is scuba diving training.

Trends in Scuba Diving Training

Initially, online education (eLearning) was introduced as a means to let dive instructors do what they love best — be in the water — while the ‘boring’ part of teaching in-class could be done at home ‘in the comfort of your pink slippers.’

What eLearning also created is an additional way to bypass the local dive shop. It is quite simple and convenient to proceed with the ‘dive theory’ part of learning to scuba dive at home — or at work! And, then, you get to your dream vacation destination where you will go underwater with a dive instructor, first in a pool, then in the magical ocean.

I do not believe this provides the best value to the consumer. You end up with rushed ‘confined-water’ (pool) training sessions because there are just so many more exciting things to do under sunny tropical skies! Cutting corners is no way to fight our excessive dropout rate. But it is a challenge to be communicating to future scuba divers that it is more valuable to them (in the long run) to be learning to dive at their local dive center before going on vacation. Therefore, the trend toward going to a dive resort after eLearning is continuing to grow.

With COVID-19, learning online instead of in-person has become the norm rather than the exception. It means that selling online courses will simply be easier than ever before. The coronavirus pandemic has accelerated the trend toward eLearning.

Within the dive industry, we’ve seen training agencies rush to launch new online learning programs — about anything and everything.

This eLearning trend is here to stay, and it means that it is becoming even easier to bypass the local dive shop.

“The shift of learning from outside the home to inside has blurred the lines between learning and leisure.” McKinsey & Company

To counteract this trend, local dive shops would need to reach local consumers while they are researching ‘scuba diving in Fiji’ or ‘PADI certification in Cozumel.’ Even with an unlimited online marketing budget, this would be a tough challenge. And local dive shops barely have any marketing budget!

Trends in Scuba Gear Distribution

This was the last leg on which local dive shops could still hope to stand. And there would be a lot to say about this! But I will move as quickly as possible to discuss ‘what to do about these trends.’

Selling scuba diving equipment is the way most local dive shops have kept the lights on. The cycle of extracting money from clients in a local dive shop has, for the most part, be in this order:

1. get them in with cheap scuba lessons,

2. sell them overpriced dive gear, and

3. book them on a dive trip to sell them more courses and equipment.

With the beginning (training) and the end (diving) of this cycle bypassing the local dive shop, it is making it hard for local dive shops to keep their lights on! Scuba divers going straight to the dive resort are often not even aware of the existence of a local dive shop.

And that’s only one trend.

Another significant trend with dive gear has been a reduction in “sales per diver.” New scuba divers tend to buy less scuba equipment than their male baby boomer predecessors. This could be an entire post in itself. Make sure to subscribe to Scubanomics at the bottom of this article.

Otherwise, a crucial development in retailing, of course, is eCommerce. That’s another trend we’ve seen surging during this worldwide pandemic. If you are not convinced, look at this graph from McKinsey & Company, a renowned US-based management consulting firm that advises on strategic management to corporations, governments, and other organizations.

Just like eLearning is now part of everyday life, eCommerce is now more accepted than ever before. The dive industry can’t continue to ignore this fact.

Why has eCommerce been so slow at being implemented in the dive industry?

There are numerous reasons why eCommerce has been slow at penetrating the scuba diving industry.

For one, dive industry leaders have continued to maintain that the local dive shop was, and ought to, remain the focal point of the industry. This was based more on nostalgia than on sound business principles.

Can local dive shops operate an eCommerce site in a way that will satisfy today’s consumers? No. It would require an investment far superior to what a local dive shop owner could afford.

When shopping online, consumers expect speed and convenience. Delivery has to be tomorrow, or earlier! And convenience means that a scuba diving equipment website should have all models in all sizes and all colors. Our internal distribution issues are none of their concern! On this front, as for dive travel, the internet is providing more immediate value to the scuba diving consumer than the local dive shop with its limited inventory and product knowledge.

By pretending that local dive shops were able to continue to satisfy evolving consumers with a small, undercapitalized store, the dive industry has simply delayed the inevitable.

‘Direct to consumer’ is how most dive gear manufacturers will try to offset a reduction in scuba gear sales in local dive shops. We can already witness it on Aqualung’s USA website, which is now a full-fledged eCommerce website.

You can’t blame dive gear manufacturers from bypassing local dive shops — they were the last to do it after scuba diving certification agencies and dive travel.

New Distribution Process for Scuba Diving Products & Services

The local dive shop is no longer ‘key’ in reaching scuba diving consumers, and it is facing an existential challenge: What is the new raison d’être of the local dive center?

A Redefined Local Dive Center

First, let’s address the elephant in the room.

I can hear you yelling at me through your smartphone screen! “Local dive shops are crucial for the diving community. They provide air fills as well as access and information on local dive sites.”

Yes. I know.

In fact, the current coronavirus pandemic is contributing to making local dive shops more of a dive destination than merely an ‘originator’ of clients for dive resorts in the tropics. But here’s the thing… That’s about scuba diving (the activity), not selling gear.

Local ‘dive centers’ can still bring value to scuba diving consumers. Dive ‘shops’ provide very little value nowadays.

Shaming people into buying dive gear from you because you are providing air fills was always a non-sustainable business scheme, and it is now utterly disconnected from reality.

A local dive shop sells six different products and services to scuba divers:

· Education / Training

· Equipment / Toys

· Experience / Travel (the activity of scuba diving)

· Rental Dive Gear

· Repair and Maintenance

· Refills

The first 3 are the big ones. They are known as the 3Es or the 3 Ts.

We’ve already discussed them. These products and services no longer need the local dive shop to reach end-users. And in many cases, the scuba diving consumers find more value when shopping outside the local dive shop. ‘Value’ includes convenience, product knowledge, and availability.

We need to face reality: the 3 Es (or 3 Ts) are bypassing local dive shops, and that trend is intensifying.

So, now what?

You can only swim against the current for so long!

The way to be successful in any business is by bringing value to consumers. And that could be in the last three services listed above. They can more hardly be remotely provided.

It is conceivable that repair & maintenance and rental gear could eventually be provided from a centralized and remote location. But for now, these are services for which scuba divers may directly benefit from your local services.

In other words, the local dive shop should drop the word ‘shop’ and work on being a quality ‘dive center’.

Find a location near an appropriate local dive site. Setup a fill station for air, nitrox, and possibly trimix. Maintain quality rental dive gear to be used at that dive site by scuba divers and dive instructors. And offer repair & maintenance on scuba diving equipment.

That is a ‘local’ business.

I bet you’ll find that your profitability may even go up! Maintaining a retail store can be expensive.

At that new dive center location, the focus is on scuba diving. That’s why you want to be near a proper local dive site. You may also select a pool, especially if it’s deep enough for scuba divers to practice their skills outside of scuba lessons.

Of course, you may offer scuba diving lessons at that location, but the focus has to be on promoting ‘scuba diving’. The rest is just there to support the activity.

And now is a good time to do it. People are looking for adventures close to home.

Operating under this new business model requires that each of these services be profitable in itself. You can no longer rely on selling overpriced dive gear to subsidize the rest of your operations. It is not sustainable. It is preventing evolution in the dive industry.

Promotional & Visibility Issue

I know the owner of a local dive shop in an urban area who will be transforming his local dive business into such a dive center, dropping the in-store retailing of dive gear.

The first problem you will encounter if you proceed like him is with dive training agencies and scuba gear manufacturers.

To be listed on their website as a retailer or training center, you must be operating a store. Scuba diving training agencies and dive gear manufacturers are forcing us to maintain this non-sustainable model of a ‘local dive shop’ operating 6 businesses under one roof.

So… The h*** with them!

Your main source of new clients is likely to be Google and word of mouth.

Word of mouth and good reviews will be easier to get if you concentrate your energy, money, and time at providing what you are good at, instead of trying to be everything to everybody. You got into diving because you love diving. Focus on that! That’s how you will be able to offer consistency in the quality of the experience under your personal craft brand.

This is how you can plan to make a good living out of your passion for scuba diving.

Furthermore, soon, the most significant part of your revenues should come from repeat business because your focus is on the adventure of scuba diving. Your business model is based on people diving locally. It is no longer based on quickly churning new entry-level scuba diving certifications to please the PADI and SSI of this world.

Otherwise, Google is not like your dive training agency. You do not need to operate a retail store to be listed as a business on Google map. The same principle applies to Facebook. Take advantage of that!

It will be good for you — and for the dive industry.

It’s always been ridiculous that consumers searching how to ‘learn to dive’ on Google where being directed to ‘retail stores’ selling gear, while the actual location to take the scuba lessons was often miles (kilometers) from there!

This is a business opportunity for your local diving business, and it can be an exciting transformational time for the scuba diving industry.

A Future Scuba Diving Brand Based on The Experience

The scuba diving industry is lacking a reliable worldwide brand. Scuba diving is a global activity, no matter where you live. And the experience you encounter under Brand A in dive destination X is usually totally different than the experience you discover under the same Brand A in dive destination Y.

Since scuba diving is an activity where safety matters, scuba diving consumers need to have ‘trust’ in the quality of the experience they will encounter, everywhere they go.

Eventually, we will see a scuba diving brand establishing itself as a provider of a consistent scuba diving experience at all locations. The focus will be on the consistency of the quality of the activity of scuba diving.

Keep an eye out! That is the brand under which you would want your reborn ‘local dive center’ to be operating.

Sunken Treasures: What Makes Divers Love Wreck Diving

Howard Ratsch — Sun, 11 Oct 2020 12:59:04 GMT

Educational Blog

Sunken Treasures: What Makes Divers Love Wreck Diving

For some divers it’s...

https://dtmag.com/thelibrary/scuba-wreck-diving/

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

By Dive Training

November 2, 2019

The sport of scuba diving is certainly diverse, with something for everyone — at every depth and all experience levels. For some divers it’s captivating coral reefs with rainbows of colors and fascinating tropical fish. For others it’s the excitement of encountering sharks, rays and other large animals. Cave diving is another pursuit driven by the quest for discovery and an attraction to uncharted tunnels and passageways. But just what is it about shipwrecks? The interest in wreck diving seems to have increased, as evidenced by the greater number of wrecks deliberately sunk as “attractions” for divers to enjoy. Whether they’re sunk intentionally as artificial reefs or recently discovered archaeological treasures hidden in their watery graves for centuries, for whatever reason, shipwrecks draw divers.

Wreck Diving and the ‘Why’

Ships end up on the bottom of the ocean, lakes and rivers due to navigational errors, collisions, storms, wartime casualties or as a result of onboard mishaps such as fires or explosions. Also, there are more and more ships now being sunk intentionally to create artificial reefs. In general, shipwrecks in shallow waters and close to shore are the easiest to access and dived the most. Deeper wrecks and ones in more remote areas are dived the least. Many remain undiscovered or undived. With technological advances in sonar and magnetometer technologies, new wrecks are found every year in all oceans of the world. And more and more ships are also being sunk purposely to form reef environments to benefit divers and fishermen.

The fact that shipwrecks offer a habitat for marine life is especially important in areas that have few natural reefs. The many flat, featureless areas of the Gulf of Mexico’s continental shelf make it prime for artificial reefing. The USS Oriskany sunk off Pensacola, Florida, in May 2005 and the Texas Clipper put to rest in Texas waters off South Padre Island are two examples of ships-to-reefs.

Wreck Diving Training and Safety

Wreck diving poses a unique array of hazards for any diver. Because so many wrecks constitute snags and obstructions on the seabed, trawler nets and high-test monofilament fishing lines are commonly strewn across wheelhouses and hulls. Now factor in low or no ambient light and an overhead environment that can easily trap a diver and prevent free ascent to the surface. Inside there may be sharp edges, loose cables, structurally unsound bulkheads, and a maze of passageways. Many wrecks fill with silt or mud that can easily stir, resulting in reduced visibility and serious orientation challenges. A diver trained only to an Open Water level has no more business penetrating a shipwreck than entering a cave.

Wreck diving is an advanced skill and requires special training and equipment. But the necessary skill sets for wreck diving vary widely depending upon the specific circumstances: depth, water temperature, condition of the wreck, sea or lake conditions, and the degree of penetration, if any. Whereas an Open Water certification is adequate training to dive outside and around a shallow, tropical-warm water, well-lit, “trap-free” wreck in, say, Bermuda, to safely dive a deep, coldwater wreck like the Andrea Doria is the other extreme that requires special equipment and a training and experience level way beyond Open Water. Many wrecks at recreational depths are intermediate-level dives most of the time but as conditions change, namely current or visibility, they can transform into very advanced dives.

The best advice is to do plenty of homework on wreck diving and get additional training before attempting wreck penetration.

§ Talk to the dive operator about the wreck or wrecks to make sure you have the proper skill level, experience and equipment for the dive.

§ Make certain you are properly outfitted for wreck diving and your gear is streamlined and snag free. Check for proper hose lengths and dive with only essential gear. Essentials while wreck diving may include two knives or cutting tools, primary and spare lights, reel and line, lift bags, alternate and redundant air supplies or more depending upon the dive.

§ Divers making repeat dives to a wreck need to be cognizant that the sea is constantly taking its toll. A section or a wreck that was sound and stable a few months ago may have become unstable over time.

§ Also, even after completing advanced and wreck diving courses, always take one step at a time in your progression as a wreck diver. Never make a dive changing more than one new variable. For example, if you are accustomed to warm-water diving, start with a wreck in warm water and begin by exploring only the outside of the wreck. Attempting a first-ever dry suit dive coupled with first-ever penetration is taskloading, and the load might just be too much too handle in one outing.

Penetrating a wreck is a serious decision and should never be done on a whim without solid preparation, proper equipment and a well-thought-out plan. Wreck diving holds a wealth of opportunity for exploration and discovery. From the Great Lakesto Great Britain, and from North Carolina to the South Pacific, there’s a near endless list of wrecks waiting to be explored. Start training now and you’ll have a lifetime of adventure waiting for you as a wreck diver.

Maritime History

In all likelihood, the first boats built go as far back as the Stone Age when dugout canoes were used for fishing. Ancient civilizations relied upon rivers and seas for fishing, transportation and trade routes. As early civilizations developed, man realized that the most practical method for moving large quantities of materials or large numbers of people long distances was by floating them in a vessel. Ships clearly affected the course of our civilization. Historical records have tremendous value but artifacts provide a different insight to where we came from and how our ancestors lived their lives. Shipwrecks really are portals to the past. Many clues to where we came from remain hidden in ancient wrecks in the sea.

The use of navigational methods dates back at least 5,000 years. In 3000 B.C. the ancient Egyptians developed the first vessels powered by wind. Egyptians used their wooden-hulled ships to explore the far reaches of the Red Sea. But the Aegean Seagets the credit for being the cradle of maritime history in the Western Hemisphere.

“Before there were shepherds or farmers in Greece, there were sailors,” says George F. Bass, pioneer and father of underwater archaeology. In the early Bronze Age (3000 B.C.) sailors moved copper and bronze materials between Crete, Asia Minorand the Greece mainland. But by 2000 B.C. the Phoenician civilization had developed a maritime trading economy that spread across the entire Mediterranean Sea. They moved along the northern African coast returning with riches from Spain and Great Britain in ships with sickle-shaped hulls and straight-rising stem and stern posts. By the end of the first century and after a series of wars, the Romans became a major maritime power that controlled the Mediterranean, or “Inner Sea.” They were the most powerful empire in the Western Hemisphere and their elite demanded silk, spices and other exotic goods from the far reaches of that time, namely Egypt and Arabia.

During the Middle Ages, Norsemen from Scandinavia used their vessel-building prowess to raid Britain and Ireland from the sea. Their double-ended designs with dragon-headed prows were constructed of overlapping oak planking and were powered by both oars and wind. When the wind was inadequate to fill the massive square sail, up to 20 oarsmen took over to power these sleek, efficient troop carriers.

By the 15th century, Europeans were venturing out to sea establishing new commerce routes and trading partners. Soon after the historic Columbus voyage in 1492, European sailors recognized the wind patterns in the North Atlantic caused a clockwise sailing route to and from the New World. At that time the Europeans were in heavy economic competition for natural resources and were establishing colonies to secure their country’s power and wealth. The British, French, Portuguese and Dutch were all flexing maritime might to stake their claims. In 1578, Sir Francis Drake became the first to circumnavigate the globe in a galleon-design merchant ship. Later the sleeker, faster clipper ships were used to further expand trade between the West and the East.

Maritime commerce in America’s Great Lakes has its roots in the days of the French fur trade. But it wasn’t until after the War of 1812 that permanent settlements flourished and commercial shipping expanded. Ship traffic picked up during the Civil War era and increased steadily through the early 20th century. Schooners, paddlewheelers, freighters, and passenger cruise liners crisscrossed the often treacherous waters of the Great Lakes. Over the years, thousands never made it to their final destinations.

America’s first Continental Navy was established in 1775 with only six frigates. Naval ships and their designs were crucial in the early years of the United States, from the Revolutionary War and through the War of 1812 and the Civil War. Ship design progressed from sail and oar power to steam engines. Although prototype submarines date back to the late 1500s, it was during the 19th century that submarine designs were advanced for effective use in warfare. The famed battle of the ironclad CSS Virginia and the USS Monitor at Hampton Roads in 1862 had a major effect on the future of naval ship design and warfare.

In the 1900s, modern internal combustion engines replaced steam engines and steel-hulled ships gradually replaced the wood-hulled fleets. Ocean liners replaced sailing vessels while the navies retooled their fleets with destroyers and armored cruisers. The Germans used submarine warfare in 1917 to strangle the Allied shipping commerce and World War I saw the first use of aircraft carriers.

By the time the United States entered WWII, German U-boats were stalking and sinking Allied ships along the East Coast of the United States and Canada as well as in the Gulf of Mexico and the Caribbean. German submarine technology and production advanced rapidly. More than 1,100 U-boats were launched during World War II, but by 1943, the Allies were producing ships at a rate faster than the U-boats could sink them. Eventually new detection technologies and improved naval tactics resulted in fewer U-boat casualties. In the Pacific Ocean between 1942 and 1945, hundreds upon hundreds of ships were sunk in hard-fought battles across the Pacific southwest region.

In July 1956, the Italian passenger liner Andrea Doria collided with the MV Stockholm near Nantucket, Massachusetts. It went down in 250 feet (76 m) of water that rarely is above 48 degrees Fahrenheit (9 degrees Celsius). In 1991 the maritime tragedy was the Salem Express and in 2006 it was the Al-Salam 98. Both were Egyptian ferries heavily loaded with workers and pilgrims that capsized in the Red Sea. Every year trawlers, tankers, ferries, cruise ships and even submarines end up wrecked underwater.

Marine Archaeology

Part historian and part scientist, archaeologists thrive on painstaking efforts to locate, retrieve, identify and catalog artifacts. They are trained to discover and preserve the lost and forgotten, whether buried in the ground or hidden on the bottom of the sea.

Most marine archaeological sites are shipwrecks but some are the result of earthquakes. There are also ancient villages once located near the sea that are now underwater due to rising sea levels since the last Ice Age. For shipwreck sites, the ship, the cargo and the crews’ personal effects are all important for better understanding the social, economic and political conditions of the past.

The chemical composition of the water environment, depth, temperature and level of light are all factors that can affect the condition of a wreck over time. Deeper wrecks tend to be better protected whereas shallow wrecks can be subject to commercial activities such as shipping, fishing, and oil and gas development. Shallow wrecks can also be affected by wave action from hurricanes and storms or from surf action. Salt water will rapidly corrode iron-based wrecks and artifacts. Sea organisms like the teredo navalis worm destroy wood and other organic materials. Fresh water is significantly less hostile than seawater. The cold, freshwater wrecks in the Great Lakes are incredibly well preserved, and many are almost fully intact after hundreds of years of submersion. The unusually low deterioration rate in this environment sustains an underwater museum for schooners, side-wheel steamers, passenger freighters and brigantines. Wooden barkentines from the 1800s remain upright with standing masts and secured yard arms.

In the sea, a cover of sediment can preserve an old wreck by protecting it from organisms and oxidation. The dilemma many underwater archaeologists face is weighing the cost of a proper archaeological investigation with the potential value of the recorded recovery, and knowing that as the clock ticks, the underwater records are further deteriorating. Wrecks and artifacts removed from the ocean need to undergo a very special and lengthy preservation process. It can take years to fully stabilize materials that have been in the ocean. In 1960, George Bass, professor emeritus from Texas A&M University, was the first person to lead an excavation of an ancient shipwreck in its entirety underwater. But not all historically significant shipwrecks are excavated underwater. The French explorer Sieur de La Salle lost one of his ships in a shallow Texas Bay in 1685. More than three centuries passed before it was discovered buried in mud at a depth of 12 feet (4 m). The archaeologists devised a plan to excavate the wreck in place “dry.”

From the antiquities to the modern era, shipwrecks are time capsules waiting to be opened. Some lay upright, while others upside down or resting on their sides. Over time many become buried in the silt and protected. Ones left exposed to the harsh elements of the sea eventually break into pieces, crumble and become a scatter of parts and pieces.

ARCHAEOLOGISTS VS TREASURE HUNTERS

Marine archaeologists and treasure hunters have been at odds for years. Archaeologists complain that treasure hunters disturb and often destroy wreck sites. They say treasure hunters often diminish their ability to systematically obtain knowledge from the remains of the ship. Marine archaeologists are especially critical of treasure hunters seeking financial gain over historical recovery and knowledge. Archaeologists often accuse treasure hunters and collectors of depriving them of finds and destroying critical information contained in the wreck. At best the treasure hunters are deemed ignorant of proper recovery and cataloguing techniques and, at worst, they are called looters.

Many treasure hunters make the simple argument of “finders keepers” and rely on Admiralty Laws to support their salvage claims and treasure finds. With the spirit of adventure and itch for mystery fueling countless hours of research followed by costly searches of the depths, the finders argue they paid their dues and deserve the spoils for the risks taken. They claim that archaeologists overplay the “historically significant” card. They insist that many shipwrecks are no more than wrecked trucks or buses that had hulls instead of wheels. And it doesn’t have to be a gold or silver find. It may be an artifact as simple as an old bottle or a brass spike. Purist wreck divers argue for leaving everything as it is for others to see and for the next generation to enjoy, yet collectors often argue that if they don’t take it now, the sea eventually will. Teddy Tucker, Bermuda’s pioneer wreck salvor, once said that marine archaeologists “want to control everything.” He contends that many archaeologists recover important artifacts only to load them in warehouses instead of making them accessible to the public. Another complaint is that the marine archaeologists don’t do enough to educate the layman on the significance of wreck artifacts. The “treasure hunter versus archaeologist” arguments continue but it is inarguable that the search for artifacts of the past inspires many.

USS HATTERAS

A significant event in U.S. history occurred off the coast of Texas on January 11, 1863. The USS Hatteras, a 210-foot-long iron-hulled side-wheel steamer sent south to blockade the port of Galveston, sighted a suspicious set of sails in the distance. After a four-hour chase, the Yankee gunboat armed with four 32-pound cannons caught up to an unidentified black-hulled square-rigger. Initially the vessel in pursuit identified itself as the Spitfire under British flag but as soon as the USS Hatteras commander Homer C. Blake let his guard down, the black-hulled ship announced its true identity as the CSS(Confederate State Steamer) Alabama and blindsided the Hatteras with a point-blank broadside gun blast. In 13 minutes the USS Hatteras was on the bottom in 40 feet (12 m) of water. The Alabama suffered no damage. Two Union crewmen were killed. Today most of the ship is buried beneath the sand and mud 28 miles (45 km) due south of Galveston. Parts of its 500-horsepower walking beam steam engine and the tops of both of her paddle wheels protrude from the bottom. The Hatteras is a direct link to the Civil War and it has great historical significance as a naval wreck that sank under battle off the coast of the United States.

Educational Blog

Howard Ratsch — Thu, 17 Sep 2020 19:30:09 GMT

Challenging The “Rules” of Scuba Diving: Because Not Everything is Black and White

By Dive Training

September 7, 2017

https://dtmag.com/thelibrary/challenging-rules-scuba-diving/

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

If you’re like most divers, you’ve heard of — and perhaps adhere to — procedures that are considered “normal” within our sport. A few classic “always and nevers” include: always dive with a buddy; always do your deepest dive first; always wear a snorkel; never put your mask on your forehead; always end your dive with at least 500 psi remaining in the tank and — perhaps the number one scuba diving “never” of all time — never hold your breath.

At first glance, these might seem like black-and-white concepts. Except, guess what? They’re not. At least not entirely.

This might sound like I’m on the verge of committing scuba heresy, but please take a couple of deep breaths and keep reading, because in this article we’ll examine — and even challenge — several widely accepted “rules” of scuba.

Rulemaking 101

Human beings are social creatures. We essentially want to be accepted in society, to be viewed as normal. Without diving deep into sociological terminology, the concept of norms provides a key to understanding social influence in general and conformity in particular. Social norms are the accepted standards of behavior of social groups. Behavior that fulfills these norms is called conformity. Social norms often evolve into rules, which are defined as explicit or understood regulations or principles governing conduct within a particular activity. Rulemaking is one of the basic impulses humans have for organizing and simplifying actions.

Norms — and the rules that often evolve from them — provide order in society. These are some of the reasons why most people, most of the time, conform to social norms and abide by certain rules.

The thing about rules is that sometimes they are based more on folklore than fact. And sometimes rules change when new facts are revealed. Take Nitrox diving, for instance. When it was first introduced decades ago there was a big hubbub about it being a dangerous “voodoo” gas that could potentially kill divers. It was condemned by the major scuba diving magazine at the time and banned at popular dive destinations. Now we know differently and divers everywhere are safely using Nitrox.

Those who challenge social norms and set out to bend or even break the rules sometimes find themselves at the center of controversy. They often get branded as troublemakers and might even find themselves at odds with the law. However, these people also tend to be significant change makers.

Let’s examine some commonly accepted scuba rules regarding equipment and dive practices that might be worthy of bending. If nothing else, they’re worth pondering.

Equipment-Related Rules

Always wear a snorkel.

The snorkel is a required accessory for scuba diving students and their instructors to wear during training dives. But once certification requirements are fulfilled there are instances when wearing a snorkel attached to the mask can prove problematic. For instance, it presents a potential entanglement hazard when scuba diving in overhead environments, such as wrecks or caverns. In addition, it can create drag when diving in a current.

Still, a snorkel is a useful accessory when at the surface. In recent years several innovative scuba equipment manufacturers have developed flexible snorkels that roll up small enough to fit in your buoyancy compensator (BC) pocket and/or fold into their own “shell” carrier that clips to the BC. For this reason, I’d like to edit the “always wear a snorkel rule” to read, “always carry a snorkel.” When the dive is done and you’re ready for a surface swim, locate your snorkel, attach it to your mask and you’re good to go.

Never put your mask on your forehead.

Okay, this one is a pet peeve of mine. I wrote about it in the May/June 2016 Final Check column, titled, “What It Looks Like When … Safety is Your Best Practice.” Somehow, somebody got a whole bunch of divers believing that placing the mask on the forehead is the international signal for “diver in distress.” Except, that’s just plain wrong.

It is not uncommon for a panicky diver to jettison the mask and regulator. This action is a panic response, which is an indication, or a sign, that the diver is experiencing a problem. However, it is not a signal, as in “if you are having a problem, put your mask on your forehead to signal you are in distress.” If you surface from a dive and need help, signal, “I am in distress and need help” by waving one or both arms above your head. (It’s also a good idea to use an audible signaling device such as a Dive Alert™ or whistle.) There are plenty of instances when a completely happy, non-panicky diver might place the mask on his or her forehead without incident. That said, there are times when placing the mask on the forehead might not be a good idea, like when you’re in choppy seas. If your practice is to prop your mask on your forehead upon surfacing from a dive instead of leaving it in place, you run the risk of having the mask dislodged by a wave — and getting lost to the deep.

No gloves allowed.

Believe it or not, this is actually a hard-and-fast rule in many tropical dive destinations. In some locations, divers caught wearing gloves while scuba diving, face stiff penalties. (Fines may also apply to dive operators.) The idea behind this rule is that wearing gloves encourages divers to grab — and subsequently damage — delicate corals, whereas barehanded divers will think twice about doing so because they risk being cut by sharp coral or stung by stinging marine creatures.

I wholeheartedly support the environmentally conscious intent behind this rule. However, I do not agree with the practice of strictly prohibiting divers from wearing gloves. Some divers have medical issues requiring them to protect their skin from exposure to sunlight, have clotting issues that turn a simple cut into a medical crisis or run risk of infection due to a cut. These folks shouldn’t need a note from their doctor in order to be allowed to wear gloves while diving.

This month’s Final Check column, “What It Looks Like When … You Are Careful What You Touch,” addresses the potential danger of grabbing a marine-life encrusted mooring line during a safety stop. While no one associated with this magazine promotes the wanton destruction of marine life, we think the ban on dive gloves goes a bit too far. Instead, we’d like to see industry stakeholders continue to promote environmentally safe scuba diving practices that encourage divers to avoid touching corals, while still allowing them to wear gloves when needed. For instance, a diver can easily stash a pair of gloves in a BC pocket and retrieve them for use when grasping an encrusted mooring line during a safety stop.

Always turn the tank valve back a quarter- or half-turn.

This one’s been around forever. And it’s wrong. Don’t do this. Instead, always turn the valve all the way on and leave it that way. Do not turn it back at all.

Apparently, the reason this practice got started is because someone decided that divers might inadvertently “strip” the valve by attempting to turn it on after it was already on. Tank valves are pretty hardy. The chances that you’ll damage a valve are slim. However, if you partially close the valve and then descend to a deep depth, the partially closed valve could restrict the airflow from the valve, making it difficult for you to breathe while on a deep dive. To avoid having problems with restricted airflow at depth always turn the valve all the way on. You are more important than a tank valve. Never turn it back a quarter- or half-turn.

Ruling How We Dive

Never dive alone. Always dive with a buddy.

When recreational scuba diving first started, the relatively crude nature of early dive gear made it necessary for divers to help each other out. The buddy system was born of common sense. It’s hard for many new divers to imagine going on a dive without a BC, submersible pressure gauge (SPG), alternate (or redundant) air source or a dive computer, but all these devices were absent from early dive training. They simply hadn’t been invented yet. Keeping this in mind it’s easy to imagine why having a buddy was considered mandatory. In fact, buddy breathing — sharing one tank and regulator between two divers — was a critically important skill taught in early scuba classes. Over several decades, equipment advances have enabled divers to become safer. And more self-sufficient. Thanks to the development of alternate air sources and redundant air delivery systems, and the fact that buddy breathing itself could be inherently dangerous, the buddy breathing skill has been purged from today’s scuba diving training courses.

Where it was once considered risky and even foolhardy to solo dive, the practice is slowly gaining acceptance. Several major scuba-training agencies offer Solo Diver and/or Self-Sufficient Diver certification courses aimed at increasing diver independence and reducing an individual’s dependence on the buddy system.

However, despite advances in equipment and training, the issue of solo scuba diving remains controversial. Some industry experts argue that buddy diving can carry with it greater potential risks than solo diving. Some recreational divers agree, complaining about being randomly paired with a buddy they’ve just met. Some dive operators prohibit solo diving, insisting that their customers be in buddy pairs or teams, often on guided dives. Still other dive operators allow solo diving for those qualified and equipped to do so.

A word of advice for those who wish to solo dive on a charter: reach out to the dive operator in advance to discuss your solo diving preference. Be willing to provide proof of your solo diving experience. Recognize that the dive operator has the right to deny your request to dive solo and insist that you abide by their stated operational policies. If this is the case, you have the option to seek the services of a dive operator that welcomes solo divers.

It’s also important to note that in certain areas, such as city, county, state or national parks, solo diving might be prohibited. It pays to read the fine print when planning a solo dive inside park waters.

On a personal note, I’ve made my share of solo dives, usually on shallow sites not far from shore. I have enjoyed the freedom and solitude of solo diving without any problems. I think those who are willing to accept responsibility for their own safety as a solo diver should be respected rather than viewed as reckless.

No matter where you stand on the issue of solo diving, I think we all can agree that every diver should train and equip for self-sufficiency and be able to handle potential problems that might arise during a dive.

Always do your deepest dive first.

This rule was considered law for many years, and it is still widely practiced today despite the development of sophisticated dive computer algorithms and new research into decompression sickness. Dive Training’s Senior Editor Alex Brylske revisited this topic earlier this year in an article titled, “Deepest Dive First? The History and Science Behind How We Plan Our Dives,” which ran in the January/February 2017 issue. Here is an excerpt from Brylske’s article:

“The issue of reverse profiles is sometimes confusing because the term actually can have two meanings. First, a reverse profile can refer to a series of repetitive dives where the deepest is not the first in the series. On the other hand, it can also describe a single multilevel dive that doesn’t follow the ‘stair-stepping’ procured described earlier; and the diver finds him or herself in the deeper phase of a dive after completing a shallower segment. Both procedures violate the deep-first rule.

It may surprise you to learn that the deep-first rule is a relative newcomer to the diving liturgy, traceable only back to the 1970s. The story is also an interesting lesson in the history of scuba diving.

A popular assumption is that the recreational scuba diving community simply adopted the deepest-first rule from the US Navy. Such an assumption seems entirely reasonable given that the USN Tables were the first standard for recreational scuba diving. The problem is, it’s not true. The US Navy does not now, nor did it ever, have any prohibition against reverse profile diving. In fact, one of the example dive table problems an older version of the US Navy Diving Manual involved a reverse profile. Likewise, there is no such prohibition in commercial scuba diving. So where did the rule come from?

The first suggestion to make the deepest dive first appears to have been offered in a relatively obscure reference — and only as a suggestion — by a researcher named Dennis Walder in 1968. His rationale was that by making the deeper dive first, one might crush “silent bubbles” — assumed progenitors of decompression illness — making the development of bends less likely on that and subsequent repetitive dives. But this was based primarily on theory and informed speculation, not empirical evidence. Moreover, no reference to any deep-first guideline appeared in any recreational diving literature until 1972, when the following statement was published in PADI’s Basic Scuba Course Manual (a curriculum segment of the then-current PADI Instructor Manual): ‘One very important rule — WE ALWAYS MAKE OUR DEEPEST DIVE FIRST when using the dive tables.’ No rationale was provided, though examples were often included during training showing the aforementioned advantage of avoiding decompression stops.

By the 1980s ‘deep dive first’ was growing beyond a recommendation.

By the 1990s, the mantra of-deep first was firmly ensconced in diver training materials as well as in the psyche of divers; and no prudent diver even considered violating the warning. But by this time dive computers had become standard equipment, and whether by accident or intention, divers were making — and getting away with — repetitive and multilevel reverse profile dives.”

Brylske sums it up by saying, “In all probability, the deep-first rule might never have been challenged had it not been for the widespread use of dive computers. Although the rules say otherwise, no dive computer in existence explodes, calls the police or ceases to function if the user engages in a reverse profile dive.”

Always end the dive with at least 500 psi remaining in your tank.

This statement is uttered during practically every pre-dive briefing in locations all over the world. The rationale behind it is solid; divers should plan their dives well and monitor their gauges carefully to avoid running low on — or out of — air. And responsible dive guides should remind divers to monitor their air supply to avoid an out-of-air emergency.

However, in some instances, well-meaning but overzealous divemasters might take it a bit too far. I’ve heard divemasters jokingly “threaten” divers with penalties, like, “You’ll owe me a 6-pack,” if they surface with less than the mandated 500-psi.

If a diver is nearing the end of a dive and needs to consume air below the 500-psi mark in order to complete a safety stop, the diver should feel comfortable doing so without fear of reprisal by the dive crew, because there’s simply no place for shaming in scuba diving.

Never, ever make contact with the bottom.

For these reasons, attempting to stay neutrally buoyant, kicking hard against a current while hovering a few feet off the seafloor and keeping an eye on the sharks would be impractical — and potentially dangerous. Here, kneeling in the sand is the best practice. Dive operators in other parts of the Bahamas, Fiji, Tahiti, the Maldives and other popular dive destinations follow this practice.

Those who teach underwater photography know it is better to position beginning photographers in a sandy patch adjacent to a reef than to have them crashing into the coral while just starting out with a camera. Yes, the sand biome contains marine life, but in most instances it is not as delicate as fragile corals. A diver who carefully settles on a sandy area will have minimum impact on the environment.

In parts of the world where strong currents are common, dive operators instruct divers in the use of “current hooks” as a means of having minimum impact on the environment. A current hook, as its name implies, is a large hook attached to a short length of line with a clip at the other end. The clip attaches to a D-ring on a diver’s BC. Divers learn to hook into an area of coral rubble in order to stay put in a strong current. By using the hook, they avoid grabbing the bottom with their hands.

Here’s one more real-world “contact” scenario: If a diver accidentally ventures too close to the reef, rather than kicking to attempt to move farther away, using a one-finger touch of a dead or algae-covered section of reef to carefully push up and away from the reef is likely to prevent the diver from damaging living coral.

The “look but don’t touch” mantra is ideal, but there are instances when it’s not always practical. What I’m suggesting here is careful and conscientious contact with the bottom (and with dead sections of coral) when conditions warrant it.

Always breathe continuously. Never hold your breath.

As I mentioned earlier, this is arguably the “number one rule” of scuba because breath holding while scuba diving can lead to serious injury, even death. However, there’s a however here.

I bring it up in honor of a diver I met years ago. We’ll call her Janet. I guided Janet on her first recreational dives after she got certified. She bought a weeklong dive package and her first day of diving with the dive center where I worked went flawlessly. The conditions were perfect and Janet appeared comfortable in the water. I took a few underwater photos of her, smiling and signaling “OK.” She said she had a great time.

The following morning, she was waiting at the dive shop very early when I showed up for work. She told me she wanted to cancel her dives. When I asked why, Janet explained that she’d been awake most of the night because she was worried that she might have accidentally held her breath at some point during the dive the previous day. She said, “My instructor drilled it into our heads, ‘If you hold your breath, you will die,’ and I’m just afraid. I can’t remember if I held my breath or not, but I don’t want to die.” I explained in great detail why divers should breathe continuously and avoid holding their breath. When I was finished, Janet decided not to give up on scuba diving after all. She sat out the morning dives in favor of some sleep, but was back out on the boat later that afternoon.

So, here’s my little secret about breath holding while scuba diving. I often do it when taking underwater photos. I admit this not to encourage any diver to adopt the practice of holding their breath while on scuba, but rather to add some clarity to the breath-holding issue. If you’re like me and you sometimes briefly hold your breath while stationary, it is unlikely you will risk a lung-expansion injury. The key here is the word “stationary,” as in remaining in place and not ascending. If you hold your breath while ascending, you do indeed put yourself at risk of a potentially serious and possibly fatal lung-expansion injury. This is why scuba instructors drill it into students’ heads to “breathe continuously and never hold your breath.” But if you’re like Janet and you might have briefly forgotten to breathe continuously just for a second, say, when posing for a photo underwater, chances are, you’ll be okay. Still, do as your instructor insists. Breathe continuously and avoid holding your breath.

A Question for You

If you’ve read this article all the way to the end, thank you. I hope you found it thought provoking. However, the take-home message I wish to leave you with isn’t about following rules. It’s about asking questions. Asking why we divers do or don’t do certain things is important. It’s how we learn and understand and it’s also how we grow. Not everything is black and white. I want to encourage you to ask the questions and find the answers and then question the answers if they don’t sound right. This is ultimately how we advance our sport, making it safer and more enjoyable for all.

Educational Blog

Howard Ratsch — Sat, 22 Aug 2020 12:32:34 GMT

Educational Blog

Health for Diving: A Primer on Diabetes

By Robert N. Rossier

February 13, 2018

https://dtmag.com/thelibrary/health-diving-diabetes/

This article represents the views of the author. The article has not been fact checked by myself, the Board of Directors or any member of the USA Dive Club.

We all know there are medical factors that can prevent people from diving. Epilepsy, various heart conditions, loss of consciousness, pneumothorax, some chronic diseases and even some forms of anxiety can spell trouble that may be incompatible with diving. But over the years, the list of contraindications has narrowed, allowing more to enjoy exploration of the underwater world.

One condition that has prevented some people from becoming divers is diabetes. Diabetes affects the body’s ability to produce or respond to insulin — a hormone controlling the metabolism of carbohydrates. The result is abnormal carbohydrate metabolism leading to elevated glucose levels in the blood and urine.

While this might sound innocuous, the long-term effects of diabetes are dead serious. Diabetes takes more lives than AIDS (acquired immunodeficiency syndrome) and breast cancer combined, claiming one American life every three minutes. Diabetes is a leading cause of blindness, kidney failure, amputations, heart failure and stroke. What’s more, the incidence of diabetes is growing. According to diabetesresearch.org, the number of reported cases of people living with diabetes has jumped nearly 50 percent in the past decade and it now affects more than 29 million Americans. On a global scale, diabetes afflicts more than 380 million people, and the World Health Organization estimates that by 2030, the number of people living with diabetes will more than double. Clearly, diabetes is a growing health risk and one that could affect our ability to dive safely. But, at least for some, the door has been opened for scuba diving with diabetes — that is, if the proper conditions are met and the proper protocols are followed.

Diabetes is categorized into two primary types, referred to as Type 1 and Type 2. In those with Type 1 diabetes, the pancreas does not produce insulin or it produces insufficient insulin to meet the body’s needs. Individuals with Type 1 diabetes must receive insulin injections regularly in order to metabolize blood glucose (blood sugar). In the more common Type 2 diabetes, the body may not produce enough insulin or the insulin does not trigger the cells to allow proper metabolism of glucose.

Type 1 and Type 2 diabetes are the most common forms of the disease but other forms exist. Many individuals are also diagnosed with pre-diabetes, a condition in which blood sugar is high but not significantly enough to warrant treatment. Unless changes are made to diet and exercise, those with pre-diabetes are likely to join the ranks of individuals diagnosed with diabetes.

To understand the effects of diabetes, we need to have an understanding of some basic human biology. In a normally functioning body, a number of metabolic reactions occur in response to eating. First, the digestion process in the stomach breaks the food down into glucose (a form of sugar), which enters the blood stream and is transported to cells throughout the body. The hormone insulin is secreted by the pancreas, which triggers the cells to allow glucose to enter. Through a process called glycolysis, the glucose is broken down in the production of a molecule called ATP (adenosine triphosphate), which is the source of energy in the cell. Also in response to eating, the cells also synthesize and story fatty acids and proteins. These are all critical functions for a normal, healthy body.

For the person with diabetes, this process simply does not work properly. Type I diabetes is actually an autoimmune condition. The immune system destroys the beta cells in the pancreas, which are responsible for the production of insulin. And without that insulin, glucose does not enter the cells and they run out of energy.

For Type I diabetes, those affected must receive injections of insulin at the appropriate times to control blood glucose levels and allow cells to receive the needed glucose. Eating the right foods at the right time can also help control blood sugar by controlling how much glucose is produced through digestion. Other factors including exercise, stress and general health also affect the body’s need for insulin, so getting the correct timing and dosage for insulin injections can be a challenge.

In Type 2 diabetes, the pancreas has a deficiency of beta cells that create insulin, making it unable to supply enough insulin to the body. In addition, insulin receptors at the cellular level may not respond properly to insulin, limiting the amount of glucose entering the cells and allowing blood glucose to remain elevated. Controlling diet is also important for those with Type 2 diabetes to prevent spikes in blood glucose. Medications are available to help maintain an appropriate low level of blood glucose. For some, additional medications may be available to increase insulin production by the pancreas.

The factors that determine blood glucose levels fluctuate greatly throughout every day, so for a Type 1 diabetic, determining the proper dose of insulin to take can be a complex and sometimes delicate balancing act. Too much insulin means the body consumes too much glucose, which can drive blood glucose to a dangerously low level. This low blood glucose condition, referred to as hypoglycemia, can sometimes be fatal if prompt corrective action is not taken.

With too little insulin, blood glucose can soar to dangerous levels while at the cellular level the body is starved of energy. This condition is referred to as hyperglycemia and it poses a risk of long-term complications.

The goal, then, is to take the necessary steps to maintain a relatively constant blood glucose level as we eat and perform various activities throughout the day. One way that those challenged with diabetes can help avoid the spikes that can come, is to pay attention to what they eat and when they eat it. If such an individual doesn’t eat at the right time or eats too much of the wrong thing (or right thing) at the wrong time, the system can easily be thrown out of balance. In addition to proper eating and dietary habits, other natural remedies have also been widely used to help keep blood sugar levels in check. For example, Gymnema sylvestre is an herb used for centuries in India to help control blood glucose by stimulating pancreatic function.

Numerous factors affect blood glucose levels, as well as overall health for all of us. These are of particular importance to those with pre-diabetes or diabetes. One factor that contributes to elevated blood glucose is stress. The stress hormone adrenaline increases blood glucose, releasing it into the blood to provide a needed boost of energy to meet the fight or flight needs. In a situation such as being chased by a shark, we would react physically by fighting or fleeing and that glucose would soon be used up. But what if instead we remain stationary? Many of us deal with stress on a daily basis, but we don’t deal with that stress by engaging in physical activity. Instead, we are forced to sit and deal with it. One result of that inaction can be elevated blood glucose levels.

Cortisol is a hormone generated by the adrenal glands that can elevate blood glucose. Under conditions of high stress, cortisol provides the body with glucose by tapping into protein stored in the liver. This energy can help an individual in a fight or flight situation. However, if we’re constantly subjected to stress, the resulting chronic elevated cortisol can lead to increased blood glucose levels. To help reduce the effects of stress, we need to find ways to prevent or cope with it. Strategies include everything from exercise to nutrition, hydration, music and meditation.

Sleep is not a luxury — it is a necessity that also has an impact on blood glucose. In fact, a chronic lack of sleep is another form of stress that can result in elevated blood glucose, according to an article in the December 2015 issue of Diabetes Therapy. The National Sleep Foundation recommends seven to nine hours of sleep every night to enjoy its restorative health effects.

Another factor that can predispose individuals to Type 2 diabetes is a chronically low level of Vitamin D. A study reported in Scientific American in 2009, found that 45 percent of Americans are deficient in Vitamin D and more recent studies corroborate a rising trend in Vitamin D deficiencies. But here is the kicker: a Tufts-New England Medical Center study found that those who are chronically low on Vitamin D had a 46 percent increased risk of Type 2 diabetes. While the mechanism of Vitamin D with regards to diabetes is not crystal clear, researchers suspect that Vitamin D enhances the cells’ response to insulin.

As it turns out, precautions against skin cancer may actually be depressing our levels of Vitamin D. In a 2009 Article in Scientific American, co-author Adit Ginde, an assistant professor at the University Of Colorado Denver School Of Medicine, reveals that using a sunscreen with as little as an SPF 15 reduces the skin’s Vitamin D production by 99 percent.

As divers, we understand that hydration is a factor in decompression illness but it is also a factor when it comes to blood glucose levels. As fluid in our circulatory system is decreased due to dehydration, blood glucose becomes more concentrated. This causes an increase in urine production, which worsens the dehydration. The key message here is the importance of maintaining a healthy hydration level through consumption of water and other non-sugary beverages. Drinking water can reduce blood glucose, reduce insulin resistance and reduce hunger. If plain water isn’t enticing enough, try garnishing it with a citrus wedge, cucumber slice or fresh mint leaves.

Exercise is a double-edged sword when it comes to those with diabetes. In general, exercise is an important ingredient in maintaining health for those with diabetes. But for those with Type 1 diabetes, some precautions are in order. Vigorous physical activity should be avoided when blood glucose level is too high (hyperglycemia) and insulin level is too low. Not surprisingly, this precaution is reflected in the diabetic diving protocols.

While the long term effects of diabetes are daunting, the short term effects for a person with Type 1 diabetes can be downright frightening, especially if that individual should be underwater. The effects of hypoglycemia include confusion, blurred vision, impaired judgment, physical impairment, seizures and loss of consciousness. Such conditions are dangerous not only to a diver, but also the diver’s buddy. What’s more, if the symptoms aren’t recognized and properly treated, the diver could be in grave danger.

Steve Prosterman is a Dive Safety Officer at the University of the Virgin Islands and a Hyperbaric Chamber Operator at the St. Thomas Hospital. Diagnosed with Type 1 diabetes in 1967, he became a dive instructor in 1982 and has made well over 10,000 dives with no complications. As he points out, “The main risk of diving and diabetes is the sudden loss of consciousness or altered state of consciousness due to hypoglycemia (low blood sugar). Hypoglycemia generally begins to develop symptoms when the blood sugar falls to 60-70 mg/dl and lower and can also lead to impaired judgment, physical impairment and seizures. For this reason, anyone with a history of reactions with these symptoms should not dive.”

At first blush, we might think that diabetes is an absolute contraindication to diving due to the risk of losing consciousness underwater. But according to the Divers Alert Network (DAN), individuals with diabetes who wish to dive, can dive safely in many cases. In fact, protocols for diving with diabetes have been around for more than a decade now. The caveat is that medical screening and safety protocols must be observed.

According to DAN, the first step for the prospective diabetic diver is to undergo the same medical fitness evaluation as other candidates to ensure no other disqualifying conditions exist. These include such conditions as epilepsy, pulmonary disease, heart disease and others. A person who has advanced diabetes and suffers from secondary complications may also be excluded.

Next, it must be determined that no complications of diabetes exist that may increase the risk of injury while diving. DAN’s guidelines also note that candidates should be 18 years or older (≥16 years if in special training program), with a well-established treatment history and the ability to maintain blood glucose levels efficiently throughout the course of changing demands of daily activities. Those who do not have the ability to control their diabetes (read more here) can be at risk and may not be good candidates for diving. Candidates and divers with diabetes should undergo a mandatory annual medical examination and, if over age 40, should be regularly evaluated for silent cardiovascular disease.

General precautions for diving with diabetes include limiting depth to 100 feet (30.5 m), limiting bottom time to one hour and not diving beyond the no-stop limits. It’s also recommended that diabetic divers buddy up with non-diabetic divers and that their buddy be aware of both their condition and the proper procedures to recognize and deal with a hypoglycemic episode.

Since the primary risk comes when a diabetic diver experiences a low blood glucose condition, one key to safe diving is ensuring the blood glucose is at minimum safe level — and stable — at the beginning of a dive (see sidebar). The blood glucose must be high enough prior to starting a dive that the dive can be completed without experiencing an unsafe drop in blood glucose. Measuring blood glucose is quick and easy using one of the many blood glucose monitors available on the market today. Continuous glucose monitors (CGMs) are also available to help monitor blood glucose levels and trends.

Good nutrition is important to everyone’s health and can help prevent the onset of such diseases as Diabetes. For those who suffer with Diabetes or pre-diabetes, staying healthy is, in part, a matter of making the right choices when it comes to dietary intake.

Sugars and other carbohydrates are readily converted to glucose, but the rate at which that occurs is measured by something called glycemic index. A high glycemic index indicates a food will rapidly be converted to glucose, causing a rapid spike in blood sugar. A low glycemic index means that the digestive process for that food is slower, meaning a slow production of glucose and a slower rise in blood sugar. For example, white rice rapidly converts to glucose and has a glycemic index of 72, whereas an apple, which converts much more slowly, has a glycemic index of only 36. However, the glycemic load, which includes the effect of typical portion size, may be an even better measure of a particular food’s effect on blood glucose.

Another factor that contributes to the rise in blood sugar is the quantity of food eaten. Eating smaller portions results in lower spikes in blood sugar. For those with pre-diabetes or Type 2 diabetes, simply eating smaller portions more frequently can improve the body’s ability to maintain blood sugars in the proper range. Choosing foods with a lower glycemic index and eating healthy portions, can help keep blood glucose in the normal range.

One area of conflicting research centers on the effects of caffeine on blood glucose. A study published in the June 2016 issue of the European Journal of Nutrition found that the risk of developing Type 2 diabetes was reduced for healthy, regular coffee drinkers consuming three to four cups of coffee per day. However, previous evidence suggests that high doses of caffeine can cause blood glucose to spike. The Mayo Clinic suggests that consuming up to 400 milligrams (mg) of caffeine (about four 8-ounce cups of coffee) is safe for most people, but it can cause trouble (spikes or lows) for those with diabetes. Limiting caffeine intake is a likely a good strategy for improved health.

Considering the health effects of Vitamin D, all divers should strive to maintain healthy levels of this vitamin. Many foods are Vitamin D-enhanced and may have a naturally high dose of Vitamin D. These include salmon, tuna, mackerel and vitamin D-fortified dairy products. Taking Vitamin D supplements is another health-wise strategy that could help maintain pancreatic function and help control blood glucose. The advice of nutritionists is to take Vitamin D3 with a meal that contains fat, since Vitamin D is fat-soluble and this enhances uptake. Foods rich in healthy fat include fish, nuts, avocado and olive oil.

The more we learn about human physiology, health and the effects of the underwater environment, the better prepared we are to make safe adaptations to explore the underwater world. Unfortunately, not everyone can safely enjoy scuba diving, but for many of those with diabetes, the door has been opened with safe diving protocols based on solid scientific research.

While the criteria for diving with diabetes may vary from one certification agency to another, some of the basic criteria for safe diabetic diving include good control of blood glucose levels and freedom from severe secondary complications of diabetes. As University of the Virgin Islands Dive Safety Officer and Instructor Steve Prosterman points out, “A candidate for diving should have an understanding of the relationship between the disease and exercise, be able to recognize early and handle low blood sugars on their own and not have had a serious hypoglycemic (low blood sugar) episode within the last 12 months.”

One way that diabetics can measure their ability to control the disease is with a hemoglobin A1C test, which provides a 90-day lookback at blood glucose levels and is a good indicator of how well blood glucose is being controlled. Most doctors will recommend that this test be performed at least twice a year. For diving, it may be suggested that the test results be within 30 percent of the normal range. Results that fall outside that range may indicate that better control of blood glucose is needed before a person undertakes underwater activities such as scuba diving.

Also important to safety is the person’s ability to recognize the early warning signs of hypoglycemia. Divers with diabetes must have a clear insight into the relationship between diabetes and exercise and be able to recognize and respond properly when a low blood glucose situation is developing.

Safe diving for diabetic divers requires strict protocols, as well as the development and use of good practices and habits. DAN recommends that divers make a general self-assessment of their fitness for diving on the day of the dive, as well as maintaining good hydration throughout the days of diving. Specific protocols* for glucose management on the day of diving include the following:

§ Before entering the water, blood glucose (BG) must be stable or rising with a value greater than or equal to 150 mg dL-1 (8.3 mmol L-1). Divers should complete a minimum of three pre-dive BG tests — performed at 60 minutes, 30 minutes and immediately prior to diving — to evaluate BG trends. It is noted that alterations in the dosage of oral hypoglycemic agents (OHA) or insulin on the evening prior or day of diving may help.

§ Divers should delay the dive if BG is less than 150 mg dL-1 (8.3 mmol L-1) or greater than 300 mg dL-1 (16.7 mmol L-1).

Divers must carry readily accessible oral glucose during all dives and have parenteral glucagon available at the surface.
If hypoglycemia is noticed underwater, the diver should surface (with buddy), establish positive buoyancy, ingest glucose and leave the water.
Check blood sugar frequently for 12-15 hours after diving to ensure safe levels.
In order to establish best practices for future diving, diabetic divers should log all dives and include BG test results and all information pertinent to diabetes management.
For more information, contact DAN and consult your physician.

* Divers Alert Network, Guidelines for Diabetes and Recreational Diving, Proceedings Summary | DAN/UHMS Diabetes and Recreational Diving Workshop.

Also available from DAN: Pollock NW, Uguccioni DM, Dear GdeL, eds. Diabetes and recreational diving: guidelines for the future. Proceedings of the UHMS/DAN 2005 June 19 Workshop. Durham, NC: Divers Alert Network; 2005.

Hypoglycemia is a condition where blood glucose (blood sugar) is low. When levels fall to 60 to 70 mg/dl or less, a dangerous condition exists. Some signs and symptoms of hypoglycemia of which diabetic divers, their buddies and instructors should be aware include:

§ Excessive hunger

§ Weakness or dizziness

§ Confusion

§ Unresponsiveness or inappropriate responsiveness

§ Blurred vision

§ Glazed eyes

§ Sudden mood changes

§ Irritability

Loss of consciousness or altered state of consciousness
Seizures

Diabetic divers who display these symptoms should follow established protocols. This includes exchanging hand signals to identify the problem, ascending and stabilizing at the surface (both the affected diver and the buddy) and ingestion of carbohydrates by the affected diver. The divers terminate the dive and return to the boat or beach where a blood test is performed. Such events, along with blood glucose results and other details of the event, should be recorded for future reference.

After Covid=19

Howard Ratsch — Thu, 25 Jun 2020 15:31:09 GMT

http://divemagazine.co.uk/skills/8907-serious-problems-diving-after-covid19

New Advice Cautions Against Rushed Return to Diving for Coronavirus Patients

By Mark 'Crowley' Russell

The Coronavirus pandemic has already had a devastating impact on the scuba diving world – but there's another question on divers' minds: 'What happens if I get it? Can I dive after COVID-19?' And the answer is not straightforward.

An article published in the German magazine Wetnotes (click here for a Google Translated English version) on 15 April gives an insight into the medical problems that scuba divers who have contracted SARS-CoV-2 might face. In it, Dr Frank Hartig, a senior consultant and response crisis coordinator/disaster officer for SARS-CoV-2 at Innsbruck University Hospital in Austria – and a scuba diver himself – describes some of the problems he has already encountered as a physician.

The acronym SARS – as in SARS-CoV-2, the official name of COVID-19 – stands for Severe Acute Respiratory Syndrome. SARS attacks the lungs, and while research into the long-term effects of the novel coronavirus is only just beginning, its physical impacts are all too tragically well known. Lung damage caused by conditions such as pneumonia and acute respiratory distress syndrome (ARDS) has been widely reported. It is also known to attack other organs, including the heart, although cardiac damage may go unnoticed until the heart is actually checked. Although we might not know much about the coronavirus itself, it has long been established that scuba diving with a compromised cardiopulmonary system can lead to serious injury, even death.

In his article, Dr Hartig describes his involvement with six active scuba divers who were hospitalised with conditions brought on by SARS-CoV-2 and who subsequently recovered and were discharged. When they returned for a check-up several weeks later, they all outwardly appeared to be healthy, but a closer examination proved otherwise.

'The first checks of these six divers, who came to the check-up clinically healthy after 5 to 6 weeks, are interesting,' writes Dr Hartig (translated from German). 'In two of them, we saw significant oxygen deficiency when under stress as a typical sign of a persistent pulmonary shunt. In two others, bronchial tubes were still very irritable during exercise, as in asthmatics. Four of the six divers in the check-up CT [scan] still had significant lung changes. None of the six divers can be released for diving for the time being, despite their wellbeing.'

Exercise-induced asthma is a well-known contraindication to diving, and in layman's terms, a pulmonary shunt is when blood fails to pick up more oxygen as it passes through the lungs, which leads to the body being starved of oxygen. It is often caused by fluid in the lungs, also the result of pneumonia and pulmonary oedema, a condition becoming widely recognised as a leading cause of diver fatalities.

At this stage, any questions over long-term damage to the lungs caused by SARS-CoV-2 would be entirely speculative, but it is clear from Dr Hartig's assessment that divers who have been affected by the coronavirus should not dive until they have had a thorough medical examination – even if they otherwise appear healthy. As Dr Hartig notes, if proper precautions are not taken, 'Young, COVID-healthy people who want to dive again quickly and appear healthy at first could [slip through our fingers].'

A report published on 12 April by the Belgian Society for Diving and Hyperbaric Medicine gives advice to scuba divers who may have contracted and recovered from Covid-19 based on current medical knowledge. To summarise, the report states that:

1. Risk of Infection: Someone who has been infected with COVID-19 can still spread the virus to others. In a diving context that would be especially likely when conducting air sharing or rescue training exercises. Before returning to diving, divers should, therefore:

· Wait a minimum of two, preferably three months, if they had symptoms of the virus

· Wait a minimum of one month if they tested positive for the virus but were asymptomatic.

· Those who have not been tested and never had symptoms may still be susceptible to infection and should 'observe a waiting period' after lockdowns are lifted, which may be variable depending on location and type of diving.

· Divers and dive centres should strictly observe guidelines for gear disinfection as distributed by DAN

2. Risk of Pulmonary Barotrauma: People who have had COVID-19 may have significant damage to their lungs for an unknown period of time, possibly permanently, and therefore have an increased risk of pulmonary barotrauma – or lung overexpansion injury – even if they don't make rapid, breath-holding ascents. A diver who was hospitalised with lung-related problems should wait at least three months and undergo complete pulmonary function testing and a high-resolution CT scan of the lungs before returning to diving. Divers who had lung-related symptoms but were not hospitalised are still strongly recommended to have the test.

3. Risk of Cardiac Events: Damage to the heart caused by COVID-19 may go unnoticed during the acute phase of the disease, but may lead to heart failure during diving. Therefore, it is recommended that a diver who was hospitalised with cardiac or pulmonary symptoms should, after the three-month waiting period, undergo a thorough cardiac evaluation with echocardiography and exercise testing (exercise electrocardiography – sometimes called the 'stress test'). Those who had symptoms but were not hospitalised are strongly advised to have the tests as well.

Pulmonary oxygen toxicity: It appears that some COVID-19 patients' symptoms worsened after being given pure oxygen. Although little is known about an increased pulmonary sensitivity to oxygen, the report suggests it would be 'prudent' to avoid technical diving involving the prolonged breathing of hyperoxic gas with a pO2 of 1.3 ATA or higher. Simple nitrox diving (maximum pO2 of 1.4 ATA) should not present any problem.
Decompression illness: tiny bubbles of inert gas form even on normal dives and are safely eliminated through the lungs during breathing. However, damage to the lungs may prevent the lungs' 'bubble filter' from working and lead to an arterial gas embolism or other form of decompression illness. Ddivers who have suffered from pulmonary symptoms of COVID-19 should, therefore, remain well within the no-decompression limits of their dives.

Click here for the full report (available in French, Dutch and English)

A complete assessment of the problems that divers might face following a COVID-19 / SARS-CoV-2 infection is undoubtedly many months away and, as Dr Hartig notes, any long-term medical advice will remain speculative until clinical trials have been conducted.

In the short-term, however, the advice is clear. SARS-CoV-2 can damage the lungs and the heart. Scuba diving with damage to any part of the cardiovascular system can lead to serious injury and death. Much as we might all wish to rush back into the water as soon as we can, doing so without proper medical consideration may cause more harm than good.

THE GOOD STUFF IS DEEP: DISPELLING COMMON SCUBA MYTHS

Howard Ratsch — Sat, 16 May 2020 13:14:54 GMT

Thanks to Robert N. Rossier Dive Training Magazine

https://dtmag.com/thelibrary/the-good-stuff-is-deep-dispelling-common-scuba-myths/

I remember from years past a particularly eager young diver who was seemingly obsessed with the desire to dive deeper. After all, he had heard that the “really good stuff” was in deep water, and that’s where he wanted to go. The misinformation he had received, combined with his desire to be seen by others as a dashing, daring conqueror of “the deep” conspired to make him a particularly “at risk” individual. Fortunately, through the efforts of a good instructor and more enlightened peers, he learned to be more cautious, and to appreciate the magical, mystical elements of the ocean realm that lay in safer depths.

The diving world is filled with misinformation, misconceptions, misunderstandings and plain-old myths. It’s surprising that even well-educated divers and instructors can unwittingly subscribe to these untruths, and pass them on to others. After all, we were all students, and most of us took as gospel every word uttered from the lips of our instructors. What we may not have realized is that they, too, were victims of myth, misinformation, and misconceptions.

Sometimes, especially when the information seems to make perfect sense, it’s easy to “go along” with what you’ve heard, and pass the bad data on to friends and students. In some cases, the information might be true, but the rationale is unsound. Sometimes the “myth” is partially true, or has an element of fact around which rumor and speculation have been wound. As we wade through the material required at any level of training, we must strive to separate the truth from the fiction, debunk the myths and replace them with accurate, up-to-date, verifiable information. And we need to encourage our dive buddies to do the same.

That said, let’s take a look at some of the more common myths, and the truth surrounding those issues. Among those misconceptions are untruths and myths regarding everything from general diving safety to physiology, physics and marine life.

Myth No.1: Diving is dangerous.

Of course it is. If it wasn’t dangerous, nobody would need training, now would they? What’s important to understand is that while diving presents a multitude of potential hazards, it is a diver’s knowledge, training, judgment and decision making that limits or controls that risk.

In fact, diving has an arguably good safety record. According to Divers Alert Network (DAN) Senior Research Director Petar Denoble, Ph.D., the injury rate for scuba diving is in the range of one per 2,000 participants, or an injury rate of 50 per 100,000. The Insurance Information Institute publishes injury rates substantially higher for many popular sports (2002 data), including basketball (21,300 injuries per 100,000) and golf (140 per 100,000). Diving may have an element of danger, but no more so than many other activities that are generally considered safe.

Myth No.2: Modern scuba gear is virtually foolproof.

There’s no question that modern scuba gear is well-engineered, well-designed, and highly reliable. That said, we still need to account for a fair number of diving accidents that occur each year that appear to be related, at least to a degree, to equipment malfunctions.

Data on equipment problems in diving is notoriously lacking in the industry, but an Australian report on the Diving Incident Monitoring Study (DIMS) prepared a few years back for the SPUMS (South Pacific Undersea Medical Society) sheds some light on the subject. According to the DIMS data, 457 of the 1,000 reported incidents (roughly half) involved equipment, and more than 25 percent of these resulted in harm to the diver. Similarly, DAN data reveals that roughly half of the 89 fatal dive accidents in 2002 involved equipment problems.

While such data might at first blush seem to implicate dive equipment, that perspective shifts when we dig a little deeper. In fact, the studies show that many of the equipment-related diving accidents and deaths are not “true” equipment problems. Example: Of the 52 regulator-related incidents reported in the DIMS data, only 20 were considered actual regulator malfunctions. Running out of air, panic, and other causes contributed to the remaining incidents and accidents. Similarly, while weight belts were implicated in 33 incidents out of 457 reported equipment-related incidents and accidents (7 percent), and were involved in 12 percent of the reported injuries, few of those were actually due to faulty weight belts. Many times the problems resulted from failure to drop the belt in an emergency, tangling of the belt due to improper use or placement, and other training-related issues.

The fact of the matter remains that while our equipment may be highly reliable, it isn’t infallible. Gear is generally good, but it’s no better than the person who maintains and uses it. A diver who isn’t well-trained and prepared, or who uses poorly maintained equipment, may end up suffering the consequences. On the other hand, a diver with the proper training, knowledge, and decision-making skills who takes proper care of his equipment is less likely to suffer a problem.

Myth No.3: The air in my cylinder is safe to breathe.

Air is all around us, and we all know that breathing it is generally more healthy than not. We also know that the compressed air provided by a reputable dive center is usually up to par in terms of meeting the air quality requirements specified by the industry. But we live in an imperfect world, and the incidence of air contamination is perhaps higher than some would like to admit. Informal data from some of the larger independent air testing laboratories suggest that as many as 3 percent to 5 percent of all air stations tested will fail to meet the CGA Grade E standard for diver’s breathing air. As we travel to more remote destinations, the lack of good filtration equipment combined with other factors might add up to a greater likelihood of getting a “bad” air fill.

Here again, knowledge, protocol and common sense can often help us sort out the good from the bad and the ugly. To be safe, we should buy our air from professional air stations that adhere to accepted maintenance protocols, and subject their air to periodic testing by an independent testing facility. Such results should be posted in a conspicuous location. In addition, especially if we’re using nitrox or some other breathing gas, it’s important to verify the oxygen content with a calibrated oxygen monitor.

Myth No.4: If I use a dive computer, I won’t get decompression sickness.

This is probably one of the most common misconceptions among divers today, but be careful how you address it. According to the latest data from DAN, between 70 percent and 75 percent of the divers injured in 2002 were using computers as their means of dive planning. “We have not indicated that dive computers should be blamed for DCS,” Denoble says. “Decompression sickness is dependent on depth-time profile in a probabilistic way: The deeper and longer you dive and faster you come up, the more likely that you will get bent. The ‘Safety Curve’ [no-decompression limits] was meant to indicate low-risk dives, but there is no guarantee that there will be no DCS within the ‘Safety Curve.’ As a matter of fact, many cases of DCS occur after so-called no-decompression dives.” This means that a very small percentage of divers will still get DCS, even if they have a properly operating dive computer, and use it correctly.

On the other hand, we must also understand that dive computers are exactly that — computers — and as such they can readily succumb to the “garbage in equals garbage out” syndrome. While a properly functioning and correctly used dive computer is perhaps a diver’s best friend, they are not infallible, either.

Among the many ways to put that “garbage” into our computers is to make some fairly simple mistakes, like switching computers in the middle of a dive trip (the new computer assumes you haven’t been diving yet); breathing a gas other than that for which the computer is set (air instead of nitrox, or the wrong blend of nitrox); or following inappropriate dive profiles, including “saw tooth” profiles or rapid ascents. Remember that individual physiology, use of alcohol, and challenging environmental conditions can alter the blood flow, gas diffusion, and overall absorption/desorption of nitrogen to the extent that the model used by the computer is invalid for the particular diver on the particular dive. In fact, Dr. Richard Vann of DAN says that the issue of dive computer safety has been the subject of a Project Dive Exploration study, and “the major conclusion is that the dive conditions can have significant effects on risk.”

Myth No.5: Scuba cylinders are indestructible.

Just look at these things. Thick steel and aluminum walls, heavy, and built for high pressure; no wonder they call them “tanks.” While a scuba cylinder may appear to be virtually indestructible, the simple truth is that they are engineered components, and sufficient mistreatment, neglect, or physical damage can render them unsafe. According to sources at Professional Scuba Inspectors (PSI) in Woodinville, Washington, cuts, dings, gouges, dents, corrosion pitting, and bulges must be compared with specific damage limits for each cylinder type. Damage or other conditions that fail to meet the allowable limits cause the cylinder to be condemned. Despite their outward appearance, cylinders aren’t indestructible, and deserve to be properly used, maintained and handled. It’s important to remember, too, that even though the cylinder itself is durable, most damage to the cylinder involves the valve, through which air flows into the first-stage regulator.

Myth No.6: The guide/instructor/buddy will take care of me.

It’s amazing to many of us how easily supposed well-trained divers can turn into “sea sheep,” simply following the herd without asking simple questions like, “where are we going, and how long will we stay?” All too often, divers regard dive guides as unerring, and will simply follow along. And while most of the time professional dive guides will be sufficiently conservative as to avoid decompression obligations, there are exceptions. According to the latest DAN data, 7 percent of the 348 divers injured in 2002 were relying on someone else rather than the tables or their own dive computer. What were they thinking? The take-home lesson for our students is that each of us is responsible for our own safety, and that means doing our own planning.

Other diving myths revolve around physiology and the physics of diving. Here again, we find some common myths and misconceptions that should be cleared up.

Myth No.7: If I feel warm, I am warm.

Unfortunately, our ability to sense heat loss from our own bodies is not as keen as we might expect. According to the “NOAA Diving Manual,” hypothermia can even be a problem when diving in warm waters. According to this source, “A phenomenon called ‘warm water hypothermia’ can occur even in the tropics, especially during long dives and repetitive dives made without adequate rewarming between dives. In warm-water hypothermia, long, slow cooling can take place in water temperatures as warm as 91 degrees Fahrenheit (33 degrees Celsius)… The physiological mechanisms of warm-water hypothermia have been demonstrated in various medical studies, but they still are not clearly understood. The victim in this situation may not shiver, because the drop in core temperature may not be rapid enough to activate the body’s thermoregulator defense mechanism…”

The implications here are clear: We must recognize the importance of wearing proper thermal protection, and understand that this equipment may be just as important in warm water as it is in cold.

Myth No.8: You can’t exceed the no-decompression limits on a single tank.

This is an old myth, stemming from the days when 72-cubic-foot (and smaller) steel cylinders were the standard of the industry, and virtually no one used a dive computer. While it may have seemed a good guideline, it wasn’t true back then, and it isn’t true today, especially when cylinders are larger, and divers go to greater depths wearing better thermal protection and consuming less air per minute.

Myth No.9: Divers should only drink water when diving.

Dehydration is one of the silent enemies of diving. It affects our circulatory system, and thus can alter the physics of gas transfer in the body, predisposing us to decompression sickness. While it’s true that divers should strive to maintain a high level of hydration, there’s a misconception that many of the so-called “sports drinks” are inappropriate for diving. According to Dr. Jolie Bookspan, author of “Diving Physiology in Plain English,” that simply isn’t the case. “Commercial electrolyte and carbohydrate sport drinks are not harmful to divers,” writes Bookspan. “Exercise studies are clear that sport drinks promote rehydration by helping you absorb and retain water. They stimulate your thirst mechanism to keep you drinking, and replace needed water.” According to the “NOAA Diving Manual,” divers should drink warm liquids between dives, and avoid alcohol and caffeine.

A final category of myths revolves around marine life. In fact, there’s a whole world of myths and legends regarding the nature and habits of undersea creatures, and not all the myths are as apparent as the tales of the Loch Ness monster. Here it’s best to turn to the experts, ferret out the truth, and separate it from the fiction.

Myth No.10: Sharks are a major threat to divers.

I think we can blame this one on Hollywood and the popular media. There are more than 400 species of sharks, and most of them will shy away from divers. There are of course exceptions, but proper precautions can drastically limit the risk of attack by the potential “evil-doers.” While sharks can be dangerous in certain circumstances, we’re much more likely to be injured by some other means.

Consider these facts: According to statistics from the International Shark Files project at the Florida Museum of Natural History, and the New York City Health Department, a person is roughly 600 times more likely to be bitten by a dog in New York City than by a shark when in the water. At least in the years 1981, and 1984-87, New York City documented reports of at least 8,000 cases in which a dog bit a human. The highest number of documented shark attacks nationwide in any one of those years was 14, in 1984. The number of lightning strikes offers additional perspective. Nearly as many people have been killed by lightning strikes in Florida than have been attacked by sharks, and only eight of those people have died as a result of shark attacks in Florida.

Some of the good stuff in diving really is deep, but the myths of diving can run even deeper. Legends are fun and myths are magical, but in the context of safe diving, there’s no substitute for cold, hard facts. If we strive to verify the “facts” we hear or have learned, turning to reliable sources for verification, we can help reduce the promulgation of diving myths.

Buoyancy Calculator

Howard Ratsch — Tue, 14 Apr 2020 18:23:34 GMT

https://www.scubadiving.com/training/basic-skills/buoyancy-calculator-how-figure-out-how-much-lead-you-need

Buoyancy Calculator: How Much Do You Need in Dive Weights?

Diving weights make all the difference

By John Brumm Updated: April 15, 2019

Pool Dive

Pool dive weight test

Kathy Danca Galli

It’s the bane of all divers. We want to go down, but the inherent buoyancy in our wetsuits, our BCs, our lungs and our fat cells are all conspiring to keep that from happening.

To overcome the force of buoyancy you have to counterbalance it with ballast weight. The question is, how much in dive weights will you need? While the answer is different for every diver, the goal is the same: carry enough weight to enable you to function efficiently and safely at all depths, and not an ounce more.

Divers are generally taught to define this as being neutrally buoyant at 15 feet deep while wearing an empty BC and carrying a nearly empty tank. But how do you get there? There’s the basic ballpark method — carry 10 percent of your body weight in lead. Or there’s the surface float method — in full scuba gear, load enough weight to enable you to float with the water at eye level (some would say at the hairline).

Want more of this?

By submitting above, you agree to

Scuba Diving's privacy policy.

But rather than just blindly piling on the lead, why not break it down to find out why you need to carry the weight you do, and what specifically you are counterbalancing. By deconstructing your buoyancy status, you know exactly where your counterweight needs are greatest, and that might reveal ways to reduce the amount of weight you ultimately have to carry. Here’s how:

STEP 1: Calculate for Your Body

How much weight do you need to make your body neutral? Take a few weights into the water wearing just a swimsuit. You will be perfectly weighted when you can hang motionless with half a breath, and sink when you exhale. (Using a snorkel can make this test easier.)

Tip for Shaving Ballast Weight: Lose weight. Also, work to turn your fat to muscle. Fat mass is a lot more buoyant than muscle mass, so any fat you can convert to muscle will lower your buoyancy deficit.

STEP 2: Calculate for Your Exposure Suit

Wearing your exposure suit, get into the water and repeat the procedure outlined in Step 1. Then take the total amount of weight required to get neutral, subtract Step 1’s total, and you’ll have the net buoyancy budget for your exposure suit.

Tip for Shaving Ballast Weight: If water conditions permit, cut down on the thickness of your wetsuit. A wetsuit can have two to three pounds of buoyancy for every millimeter of thickness. If you wear a neoprene drysuit, consider that compressed or crushed neoprene suits have much less buoyancy than standard neoprene. If you wear a fabric drysuit, remember that thinner undergarments have much less buoyancy than the puffy stuff.

STEP 3: Calculate for Your BC

BCs can be a huge source of inherent buoyancy, especially the older, full-featured models that have lots of traditional-style padding. It used to be common for BCs to carry upwards of four pounds-plus of inherent buoyancy, which means, of course, that you need four pounds-plus of extra lead on your weight belt to compensate for it. Fortunately, most modern BCs carry much less inherent buoyancy.

To test your BC’s inherent buoyancy, submerge it while venting all exhaust valves to bleed air from the bladder. Knead the padding in the shoulders and backpad and behind the pockets to release air bubbles. Slowly rotate the BC to enable any trapped air to escape. Be patient, allow plenty of time for water to displace the air in the material. When you stop seeing bubbles, release the BC into the water column. If it heads to the surface you’ve got some inherent buoyancy to deal with. Add weights until the BC will hang neutrally buoyant in the water. Then count up how many weights it took to get there and you’ll have your number.

Tip for Shaving Ballast Weight: Buy a modern BC. Models that have come onto the market within the last three or four years carry, on average, from one to 2.5 pounds of inherent buoyancy, and some carry none at all. Note: while most manufacturers don’t provide the inherent buoyancy of their BCs, you can always find that info in ScubaLab BC reviews. (https://www.scubadiving.com)

STEP 4: Calculate for Your Tank

The buoyancy characteristics of tanks vary widely. For example, a standard aluminum 80 is 1.6 pounds negatively buoyant when topped off, and 2.8 pounds positively buoyant at 500 psi. That’s close to a four and a half pound buoyancy differential between the beginning of a dive and the end of a dive that, of course, needs to be dealt with by adding ballast weight.

A steel tank, on the other hand, tends to start off negatively buoyant and stay that way. For example, a high-pressure 80 is about nine pounds negative when full and three pounds negative when empty. That’s three pounds that can be removed from your weight system.

Tip for Shaving Ballast Weight: Switch from an aluminum cylinder to a steel cylinder. A properly-weighted diver who goes from an aluminum 80 to, say, a HP steel 80 could theoretically take six pounds off his weightbelt.

STEP 5: Calculate for Everything Else

Gather your reg, gauges, knife, fins and any other items you regularly dive with, place them in a neutrally buoyancy mesh bag, and submerge it. The goal here is primarily to see if the total package is positively buoyant. If it is, add some weight until it becomes neutral. If it’s negative it probably won’t be by much, so consider it a ballast slush fund. It’s not working against you, and that’s all that matters.

STEP 6: Put it All Together

Add it all up. This should be very close to your target ballast weight requirements, and it should also give you a clear picture of where your biggest buoyancy challenges lie. To double-check your calculations, gear up with all the components you measured separately, get back into the water and repeat Step 1. If the above scenario played out like it’s supposed to, you should be floating at eye or forehead level in a relaxed position. When you exhale you should start to slowly sink. If not, you couldn’t be more than a pound or so off your target. Make the final adjustment and go diving.

SALT WATER VS. FRESH?

If most of your diving is done in fresh water springs or lakes, then ballast calculations should be done in fresh water. If you dive mostly in the ocean, then do the calculations in salt water. If you switch back and forth, you’ll need to adjust your ballast needs as you go. Be prepared to add anywhere from 4 to 7 pounds going from fresh to salt water.

Traveling Tale of Woe

Howard Ratsch — Thu, 20 Feb 2020 13:27:31 GMT

Copyright Disclaimer under section 107 of the Copyright Act of 1976, allowance is made for “fair use” for purposes such as criticism, comment, news reporting, teaching, scholarship, education and research. Fair use is a use permitted by copyright statute that might otherwise be infringing.

https://www.scubaboard.com/community/threads/tale-of-woe-how-i-was-that-diver-non-fatal.590118/

Thank you Ken Kurtis

I got this note from a diver I've known for a long time. Although I think there are good lessons to be learned here and suggested he post this, he's a bit embarrassed about what happened given his lengthy diving experience but said if I could sanitize it and make it anonymous, I could share the story. (And it truly isn't me in this tale.) But the point is that even experienced divers can easily make mistakes or take things for granted. The dive that starts off with you checking out mentally could spiral out of control. Fortunately, his only ends up as a story:

The wife and I did a cruise a few months ago. The cruise did not offer any scuba packages, so we contacted local dive shops on some of the islands. We picked based on reviews on TripAdvisor and reading their websites. In the end we decided we would be too busy to dive and left our gear at home (we only took our masks and snorkels), Well as it turns out, while on the cruise we decided to dive on Barbados and Antigua and recontacted the dive operators on those islands. And it did not go very well for me.

First was Barbados. My wife and I were sent down the anchor line first, then a family of resort divers was going to enter with their DM, then our DM was going to come down and guide she and I around. Well I was a little bored and the vis was terrible - maybe 20'. There was a patch of fans and coral a few feet away, so I decided to look at it. I moved in a straight line to it, looked back and made sure I could see her and the concrete anchor, then turned back to the coral. Suddenly a surge came by and vis dropped to about 5 feet. I knew I had screwed up royally, flipped my rental console over to use the compass and swim straight back while I was still oriented to the fans. But there was no compass (I hadn't checked prior to descending), and the surge was moving me around a lot. So I crept back and couldn't find the anchor. So I spent a few minutes swimming a circle pattern, then with great expectations of embarrassment, started my slow ascent of shame. About 20', the sea cleared and I saw the line. I went back down and nobody was there. I stayed a few minutes, then ascended up the line to the boat. When I was about 10', the line went slack as the boat unhooked to go after the family who had been trying to drift dive when the vis went bad and were now at the surface ready for recovery. I popped up (no audio signaling device or sausage) in 3-4' swells and saw the boat leaving. I did get their attention and signaled I was OK and then hung on the mooring buoy for about 20 minutes until after all others were recovered. I was so embarrassed at how I had managed to screw up royally in such a short time in the water. The folks on the boat felt terrible that they took us to a place that had the vis drop out leaving me lost 15 feet from my wife - they thought it was their error, but the wife and I knew it was mine. Second dive 2 miles away was wonderful.

Then Antigua. Here the dive gear was poorly fitting. It was way too small and useless for a fat guy like me. But I did not really mind the tank flopping around as the cummerbund kept coming undone. At about 45' on our way to 65' my reg started breathing very hard.

Inhaling was pulling my mask against my face. So I went to the octo and it was the same. The high pressure gauge was reading a full tank and did not dip as I breathed, so I knew the valve was on. I hesitated before calling the dive, but if it was already having trouble at 45', I did not want to have to be concerned about something failing the rest of the way while on a dive, so I found the DM, explained the situation and was escorted back the boat where I sat out that dive. Second dive with different reg was great.

LESSONS LEARNED
Next time I take my own gear. Or if I rent, I will make sure there is a compass - even in the Caribbean. I should have had a signaling device like a sausage as well. If I had taken my BC, it would have been attached and ready. I also would have been familiar with the gear and it would have fit properly.

The Antigua dive frustration was not my fault, it was just one of those things that was inconvenient, and not a significant risk. If the reg had failed while in a group, there was plenty of air to borrow for a safe return to the boat.

The Barbados dive was a risk of my own creation. I was THAT DIVER. I was headstrong and over confident. As such I inconvenienced others and thereby increased risks by requiring attention that was not then available for the others if they had a problem. As we know most serious dive problems are a series of small risk-increasing events that together become a crisis. I knew better, and yet there I was in the middle of a mess of my own creation.

I thought you might find this a fascinating study in vacation diving on a non-diving vacation. I have been a diver since 1974, you would think I would have known better.

Ken Kurtis
NAUI Instr. #5936
Owner, Reef Seekers Dive Co.

HOW TO PLAN AND ENJOY YOUR OWN SHORE DIVING ADVENTURES

Howard Ratsch — Mon, 13 Jan 2020 20:26:39 GMT

THANKS TO DIVE TRAINING MAGAZINE

and

Barry and Ruth Guimbellot

https://dtmag.com/thelibrary/shore-diving/

Have you ever wanted to strike out on your own as a diver? If yes, it’s important to recognize that there’s more to shore diving than gearing up, wading into the water and swimming off. Exciting shore diving opportunities abound, but you’ll need to do a bit of preparation beforehand.

The Perks of Shore Diving

One of the reasons shore dives are so attractive is due to the freedom you and your buddy will have when planning and enjoying your self-guided dives. You are free to choose special sites to explore, whether it is a freshwater quarry, an inland lake or an ocean site with shore access. The timing of the dive is totally up to you and your buddy — and Mother Nature — as you’ll always want to plan your shore dive when conditions are most favorable. You can decide on the time and place to dive, as well as the length and depth of the dive. And those who struggle with motion sickness will tell you they prefer shore diving to sitting on a rocking boat. And one more advantage of shore diving is that it is a cost-effective way to indulge in your passion for diving.

Pre-Dive Preparations

As independent divers, you and your buddy or buddies are responsible for mapping out your plans for the dive trip. To avoid any major problems, begin making plans well ahead of the first dive. Discuss possible dive locations where shore diving is permitted and easily accessible. Complete a checklist of all equipment needed, keeping your dive objective in mind. Also, include items necessary for setting up a base camp.

Even though you’ll be diving on your own, it pays to consult the pros at the dive center nearest your shore diving location. This makes sense and not just because it’s likely where you’ll be getting air fills and buying or renting gear, like extra dive weights or a “diver down” float/flag. They’re also the source for local expertise on your planned dive location. Chances are, they know the local sites well and might even have maps and/or charts to share, along with tips and advice about the best parking spots, entry and exit areas, and more. If it’s your first time exploring a new shore diving site, their experience will likely prove to be invaluable.

Inquire about current weather patterns and tidal variations. Check recommended websites, books or apps for additional information. Site selection will also depend on your objectives, such as exploring a shipwreck or visiting some other underwater feature.

Once at the site, visiting with other divers is also an excellent way to gain information about the area. Ask about the ease or difficulty of the entries and exits. Does the underwater terrain have slippery or sharp rocks? If making a lake shore entry, is the bottom muddy or silty? How is the visibility? Are there any potential hazards you should be aware of?

Arrive at the site early enough to observe the area before gearing up and entering. Watch for boat traffic, kayaking or jet skiers in the area, especially in lakes. Ocean activities such as parasailing, wind surfing and paddle boarding are common and typically close to shore. Keep an eye out for potential environmental challenges, such as rip currents. If you decide the area presents too many challenges, it’s best to move to another location.

Establishing a Base Camp for Shore Diving

Now that you have done your homework and found the best site for you and your buddy, it is time to set up base camp. Avoid high traffic areas and be considerate of others near you when claiming a desired spot. Anything from your car to a large tarp spread on the ground will work. Cars work well if the parking area is near enough to the dive site. You can gear up at the vehicle, stow any personal articles and lock the car before moving to the entry site. Place the key(s) in a secure wetsuit pocket in a dry pouch before beginning your dive.

A tarp spread on the ground is especially handy if you have a non-diving friend who can stay at base camp while you are diving. When spreading the tarp on the ground, be sure to keep it safely above the high water line. Place dive gear around the edges of the tarp, making it easier to gear up without tracking sand or debris onto the tarp. Secure the corners by setting extra weights or other items at each corner.

Stock the base camp with anything you may need. Provide plenty of snacks and fluids, especially water, to enjoy during surface intervals. Other important items to have handy include a first-aid kit, eco-safe sunscreen, emergency information, fully charged cell phones and DAN (Diver’s Alert Network) membership numbers for each diver. Also, remember extra parts for maintaining gear or underwater cameras.

Navigating Entries and Exits

Once the dive site is selected and base camp is set up, decide on the best entry and exit points. Also, determine an alternate exit point in the event conditions change during your dive. When gearing up for a shore dive, don all of your gear but the mask, snorkel and fins. If you wear open-heel fins that accommodate dive boots, consider buying a pair with a rugged outsole. If you normally wear full-foot fins, consider wearing a thin pair of neoprene socks with a non-skid coating on the bottom. This will help you avoid slipping and will also protect your feet from injury as you make your way in and out of the water.

Help each other gear up and then perform a pre-dive buddy check before you enter the water, confirming that your tank is turned all the way on and that all gear is in working order and that you have important accessories such as a compass and dive float/flag and line/reel. If conditions allow, wade into chest-deep water before donning your fins. Start by donning your mask and snorkel and then add air to your buoyancy compensator (BC). Once in the water, as your buddy supports you, slip on the first fin using the Figure 4 method. Switch legs and put on the other fin. Now assist your buddy as he or she dons their fins. If conditions warrant that you don your fins at the water’s edge, you and your buddy can take turns steadying each other. Once you’ve got your fins on, continue to help each other as you carefully shuffle backwards or perform a sideways “crab walk” into the water.

If you intend to do a surface swim out to the dive site, make sure you have plenty of air in your BC for comfort at the surface. You might also wish to switch from regulator to snorkel to conserve gas supply. Plot a compass heading on the way out and reverse the heading when returning to the exit point. Also, use natural navigation like heading along a wall or other natural feature.

Always monitor your gas supply and remember to plan your dive so you have plenty of breathing gas remaining for your return to the exit area. Many divers plan their dive by “thirds” — using a third of a tank for the outbound dive, a third for the return, leaving the remaining third in reserve in case of emergency.

Shore diving is best when the surf is mild. Rough surf with large waves can be dangerous and should be avoided. If this situation occurs, consider other possibilities such as using a dock or stairs to enter and exit.

Learning how to execute shore dives can be an exciting addition to your diving adventures. Just remember to do your pre-dive homework, practice necessary safety procedures and enjoy the freedom and fun scuba diving from shore has to offer.

Shore Access. A Sure Thing?

Many inland dive sites, such as lakes and quarries, are privately owned. Coastal areas are open to the public but might be situated in areas with privately-owned homes or businesses nearby or are within state or national parks. When planning a shore dive, it’s important to find out how to gain access legally — and respectfully.

When diving a private site or visiting a state or national park, an entrance fee might be required and you might also need to show proof of certification, proof of divers’ insurance (DAN or other) and you might need to sign a liability waiver and agree to abide by the owners’ rules of operation.

When using public access to ocean sites, be considerate of private homeowners. This includes avoiding parking in private parking areas, keeping the noise to a minimum and being discrete when changing out of wet wetsuits.

DIVING FITNESS AND MEDICAL EXAMINATIONS

Howard Ratsch — Sun, 22 Dec 2019 13:15:13 GMT

Our thanks to Diver Training Magazine

https://dtmag.com

The Doctor Will See You Now: Diving Fitness and

Medical Examinations

By Alex Brylske

I'm sure that there are places where I’m more ill at ease than in a doctor’s office, but I can’t really think of one. This isn’t to say that I don’t take my health care seriously. My doc is an affable and competent person whom, like it or not, I visit on a fairly regular basis. Over the past several years I’ve been poked, probed, palpated, stuck, irradiated and imaged in every way imaginable, and some that aren’t so. Heck, I even get my teeth cleaned twice a year. However, I’m not one who runs out to the doctor for a hangnail or at the first sign of a cold. In fact, as testament to my abhorrence to anything medical, there have only been two occasions in my entire adult life when I visited a doctor for something other than preventive care.

My fear and loathing of medicos goes back to my childhood. I had had two operations by the time I was 6 years old, and that much hospital experience for one so young definitely has an effect. Even as a teenager, as much as I dreamed of becoming a diver, I was initially reluctant to get certified when I learned that it would require a medical examination.

Of course, knowing one’s level of fitness is essential to safe diving because, regardless of how easy it has become, surviving underwater subjects our bodies to some pretty stressful and unforgiving situations. But what exactly constitutes “fitness to dive,” and how can we assess that? Does determining our fitness always require the insight of a trained medical professional? These questions have been debated since the beginning of recreational diving and, as in most fields, opinions and practices have changed over the years. Even today, polices on prequalification medical exams and diving fitness are not universal.

The What and Why of ‘Fitness’

In scuba diving, when it comes to assessing fitness, times have certainly changed. Years ago, many were reluctant to even consider diving because they thought it was deep, dark and dangerous. Today, it’s just the opposite. Many are lulled into diving because they view it as simple, safe and easy. Indeed, diving takes place in a relatively weightless environment, which may make it seem effortless, but it does require a degree of both health and stamina.

In determining what fitness means to you, understand that there’s no single answer; it means different things to different people. The first issue to consider in evaluating your fitness level is where and what type of diving you plan to do. Obviously, enjoying a shallow reef in the Florida Keys on a still summer morning is far less demanding than braving 8-foot seas to dive the wrecks off the New Jersey coast. Although this may seem obvious, it’s amazing how many folks will assume that their Florida Keys fitness is all they need when they one day decide to dive New Jersey or California. Your well-being demands that you be honest about what you want from the diving experience, and make sure that you don’t exceed the conditions on which you’ve based your fitness decision.

Still, even if you do decide that you’re only interested in relatively “easy” conditions and environments, things don’t always go as planned. Even the best conditions can change rapidly, and it’s these unforeseen circumstances that cause a lot of accidents. So, whatever you expect, assume that once in a while, at least, conditions will be worse; perhaps much worse. This means that you must possess not only the level of fitness required for what you normally encounter, but a “reserve,” just in case. Granted, assessing, acquiring and maintaining an appropriate level of fitness may not be easy, but never forget that Murphy’s Law is always right around the corner ready to bite you on the backside when you least expect it.

Whether you expect it or not, on any dive you may encounter long surface swimming, have to contend with strong, changing currents or just deal with being at the surface in conditions akin to a washing machine during the rinse cycle. All require more fitness than walking from your easy chair to the fridge. Unanticipated and strenuous physical tasks are part of the diving experience in any environment; therefore you must not have any health conditions, or take any medications, that may impede your performance.

Assessing your fitness also isn’t a one-time event. When I started diving as a young teenager, there were few physical tasks a diver might encounter that I couldn’t handle. But to assume that’s still the case more than three decades later is a recipe for disaster. So, the next time you’re filling out your logbook, take a few minutes to ask yourself a few simple questions: Did I encounter conditions that were close to or beyond my physical capabilities? How likely is it that these conditions may occur again? Do I need to reconsider my “comfort envelope” or try to improve my fitness? The answers require a great deal of self-honesty, but the exercise may be the best thing you’ll ever do for your health and well-being.

Finding a clear method to assess and quantify your level of fitness isn’t always easy, but there are some basics you can keep in mind. First, if you can’t walk around the block without a rest, or if you’ve never even tried, diving at any level probably isn’t something you should try (or continue). At least, not until you’ve improved your conditioning. A very minimal guideline for fitness is the ability to walk a mile (1.6 km) within 12 minutes. If you can’t do this, you should plan to exercise for at least 20 minutes four or five time per week, but only after you’ve gotten the approval of your doctor. And if possible, add swimming with fins to your routine. A useful measure that I’ve always given my own students, based on years of teaching experience, is this: No one should consider themselves prepared for a certification course who cannot swim at their own pace, using a mask and fins, at least 200 yards (182 m) without stopping and/or becoming exhausted.

Restrictions and Red Flags

Aside from physical fitness, divers and would-be divers must also consider how any existing medical conditions can affect their health and safety. Surviving in an environment that’s 800 times denser than the atmosphere can present problems that might never arise while sitting in your living room, or even engaging in moderate physical activity on terra firma.

First, let’s consider temporary conditions such as colds, flu, injury or even pregnancy. All should be considered reasons to curtail diving until the effects have passed. Colds, flu or allergy attacks cause swelling or blockage in the sinuses and eustachian tubes, which means pressure equalization will be difficult or impossible. Injuries can leave you with restricted strength, stamina or mobility, and can even put you at a greater risk of decompression sickness due to alterations or restrictions in blood flow. Furthermore, when diving with an injury, the accompanying pain could mask symptoms of decompression sickness. So it’s best to postpone diving until you’re fully healed. Lastly, diving while you are or could be pregnant is considered a no-no for one simple reason: We just don’t know enough about its effect on the developing fetus, so why take the chance? Can any hour spent underwater be worth the risk to a child’s life or quality of life?

It should be obvious that you must take into account the effect of any medications. This goes for both prescribed and over-the-counter (OTC) meds. Frankly, most medications have no effect on diving, but some definitely do. They may cause drowsiness or fatigue, which may make you more susceptible to nitrogen narcosis, or impede your thinking at just the time thinking is most critical. Other medications, as well as illicit drugs, can affect heart rate even in those without heart problems. Clearly, if you plan to dive, it’s especially important to read the warning labels before using any drugs. And it’s just downright stupid to dive while taking any recreational drugs.

Another concern that’s foreign to any landlubber taking meds is whether and how the increased pressure at depth can affect any drug. There is always a possibility of such an unexpected reaction to medications, and some drugs are noted particularly for pressure-induced side effects. But the problem is that these reactions can vary from diver to diver, and even from day to day. So, the first step in preventing a dangerous situation is knowing well in advance what side effects any medication has on you before using it while diving. It isn’t smart to pop a pill for the first time just as you’re about to enter the water. This is true even of common OTC drugs like cold and allergy or seasickness medications.

The effect of diving on prescription medication can be a very complex issue, and requires a knowledgeable doctor’s advice. Regardless, always remind your doctor that you’re a diver when he or she prescribes a med. And, if your doc isn’t up on how diving can affect your condition or medications, you should be prepared to provide some resources. (See the sidebar “Educating Your Doctor” on Page 34.)

Some medical conditions aren’t temporary, and these can have major consequences for divers. Two of the more common concerns are asthma and diabetes. Both are becoming epidemic in many regions of the world, including North America, the Caribbean, and the islands of the South Pacific; and many believe that this is the result of lifestyle and the degrading quality of our environment. This is a serious problem for all segments of society, but it poses additional problems for the diving community. For decades there has been much debate about whether to allow those with either condition to dive; and at one time the answer was quite simple: no. But many have questioned such a ban on diving, and today, after careful medication evaluation, some asthmatics are permitted to dive.

Diabetes, as well, is a chronic condition that’s been recently reconsidered by diving medical experts. Today, rather than a blanket disqualification, divers and diving candidates with diabetes are evaluated on a case-by-case basis with an appropriate medical specialist. A similar situation exists for one of the most common disorders in almost every developed society: cardiovascular disease. (For more information, see “The Heart of the Matter,” Dive Training, April 2006.) Research and debate continue regarding both asthma and diabetes, and it’s likely more issues and findings will appear.

This Will Only Hurt a Little

Whether you’re a diver or not, the cornerstone of good health is a regular physical exam. Opinions on how often this should happen seem to vary; and to be perfectly honest, after graduating from college I didn’t set foot in a doctor’s office for almost 20 years. But that all changed when I hit the big 4-0, a milestone no one should ignore. Since then I’ve had regular annual checkups, along with the associated diagnostic, age-appropriate tests involving treadmills, CAT scans, endoscopes, rubber gloves and assorted other accouterments of medical technology.

The issue of physical examinations for divers has undergone quite an evolution. Even today, policy varies from country to country. As I mentioned, when I got certified, everyone was required to first secure medical approval from a physician before being accepted into a class. But in North America, that hasn’t been the case for a long time. As many of you no doubt know from your experience, some of you had to have physical exams, while others didn’t.

North American-based diver training organizations require that all candidates for instruction complete the Recreational Scuba Training Council’s “Medical History Statement and Questionnaire.” (A copy of the form can be downloaded from many sources; just type in the search term “RSTC medical form.”) As the form explains, its purpose is to find out if a perspective diving student should be examined by a doctor before participating in training. A “yes” response to any question doesn’t necessarily disqualify someone from diving, but it does indicate that there could be a pre-existing condition that may affect safety. Therefore, the candidate must seek the advice of a physician before engaging in diving activities.

Some believe that this approach is inadequate, contending that everyone new to diving should first have medical clearance from a physician. In fact, some countries such as Australia require this. But is this additional expense and inconvenience really warranted? Some who have studied the matter don’t think so. For instance, the UK Sport Diving Medical Committee found that examination by a physician was largely unhelpful in identifying divers with significant medical conditions, and concluded that a health questionnaire, like the current medical history form, is perfectly sufficient. A similar result came from a study six years ago published in the British Journal of Sports Medicine.

However, this selective nature of medical exams does not apply to some divers. All commercial divers, including professionals such as divemasters, dive control specialists, assistant instructors and instructors, are required to have full medical clearance before they’re accepted into training. Scientific divers, including most divers in university programs and those working under the guidelines of the American Academy of Underwater Sciences (AAUS), also require full medical evaluation before training, and while active in such programs.

For recreational divers, the current medical standard has been in effect for almost two decades. The questionnaire was developed by the Undersea and Hyperbaric Medical Society (UHMS) and Divers Alert Network (DAN). (More information about the form is contained in “Assessing Your Medical Fitness to Dive” on Page 36.)

In the end, however, the final arbiter of who can enter a diving course, for medical reasons or otherwise, is that of the instructor. In fact, based solely on his or her judgment, an instructor may require anyone to secure medical approval from a physician, even if the candidate has indicated no affirmative answers on the questionnaire.

We all like to think the best of ourselves. And often our image doesn’t reflect reality. Usually, this has little potential to do harm to anything but our ego. But fitness for diving is a different matter. When it comes to fitness, lying to yourself or others can put both you and your buddy at serious risk. Remember, no diver ever thought that they weren’t coming back from their dive.

Educating Your Doctor

As we all know doctors are very busy people. Their medical school training is intense, and with continuing advances in medical research, they have to know more and more. So, it’s no surprise that a subject like diving medicine doesn’t receive much, if any attention, in either medical school or afterward. In fact, if a doctor doesn’t take up diving personally, he may know less about diving medicine than a knowledgeable scuba instructor. This isn’t intended as a slam. It’s just that, in the scheme of things, scuba diving isn’t a very common activity. So, most doctors only rarely deal with divers and would-be divers. As a result, when it comes time for a diving medical exam, you may find yourself in the delicate situation of having to educate your doctor.

But the situation isn’t as daunting as it may sound. The RSTC “Diving Medical Statement and Questionnaire” contains a section designed just for this purpose: “Guidelines for Recreational Scuba Diver’s Physical Examination.” It includes three pages of detailed instructions with 16 medical references. So, when you show up to your doc’s office, be sure that you take a copy of the entire six-page form, not just the part he or she has to sign.

The guidelines discuss areas of concern for divers, and what to look for in a medical assessment. Temporary, relative and severe risk conditions are listed for the neurological, pulmonary, gastrointestinal, orthopedic, hematological, metabolic/endocrinological and otolaryngological systems. There’s also a segment on behavioral health. At a minimum, the examination should include these points. The list of conditions is not all-inclusive, but contains the most commonly encountered medical problems.

The guidelines define “temporary risks” as those that are responsive to treatment, allowing the student to dive safely after they have been resolved. “Relative risks” refer to conditions that exist but, in the judgment of the physician, are not contraindicated for diving. Finally, “severe risk” implies that an individual is believed to be at substantially elevated risk of decompression sickness, pulmonary or otic (ear) barotrauma or altered consciousness with subsequent drowning, compared with the general population. In these cases, as the guidelines state, “The consultants involved in drafting this document would generally discourage a student with such medical problems from diving.”

The guidelines conclude by informing physicians that medical professionals of the Divers Alert Network (DAN) associated with Duke University Health System are available for consultation. If you find that your doc would like even more insights, here are some additional references:

“Medical Examination of Sport Scuba Divers,” 3rd Edition, A.A. Bove, M.D., Ph.D (ed.), Best Publishing Company, P.O. Box 30100, Flagstaff, AZ 86003-0100.

“The Physician’s Guide to Diving Medicine,” C.W. Shilling, C.B. Carlston and R.A. Mathias, Plenum Press, New York, New York (Available through the Undersea and Hyperbaric Medical Association, Bethesda, Maryland)

Assessing Your Medical Fitness to Dive

The “Diving Medical Statement and Questionnaire” has been produced under the auspices of the Recreational Scuba Training Council and endorsed by the Undersea and Hyperbaric Medical Society (UHMS), Divers Alert Network (DAN) and more than two dozen of North America’s top diving medical specialists. To assess whether an individual should have medical clearance to enroll in a scuba course, here are the areas it addresses:

First, the questionnaire addresses those over 45 years of age. For this group, a positive response to smoking, high cholesterol, family history of heart attack or stroke, high blood pressure, diabetes (even if controlled by diet alone), or if you are receiving medical care means a trip to the doctor’s office.

It then goes on to ask all applicants if they have or have ever had any of several medical conditions, listed below; and if they take any prescribed medications for anything other than malaria prophylaxis or birth control. Female diving candidates are asked whether they are, could be or are attempting to become pregnant.

Again, an affirmative response to any of these questions or conditions, and a doctor’s approval is required for continuing with your wishes to become a certified diver.

§ Asthma, or wheezing with breathing, or wheezing with exercise.

§ Frequent or severe attacks of hay fever or allergy.

§ Frequent colds, sinusitis or bronchitis.

§ Any form of lung disease.

§ Pneumothorax (collapsed lung).

§ Other chest disease or chest surgery.

§ Behavioral health, mental or psychological problems (panic attack, fear of closed or open spaces).

§ Epilepsy, seizures, convulsions or take medications to prevent them.

§ Recurring complicated migraine headaches or take medications to prevent them.

§ Blackouts or fainting (full/partial loss of consciousness).

Dysentery or dehydration requiring medical intervention.
Any dive accidents or decompression sickness.
Inability to perform moderate exercise (i.e., walk 1 mile [1.6 km] within 12 minutes).
Head injury with loss of consciousness in the past five years.
Recurrent back problems.
Back or spinal surgery.
Diabetes.
Back, arm or leg problems following surgery, injury or fracture.
High blood pressure or take medicine to control blood pressure.
Heart disease.
Heart attack.
Angina, heart surgery or blood vessel surgery.
Sinus surgery.
Ear disease or surgery, hearing loss or problems with balance.
Recurrent ear problems.
Bleeding or other blood disorders.
Hernia.
Ulcers or ulcer surgery.
A colostomy or ileostomy.
Recreational drug use or treatment for, or alcoholism in the past five years.

A Note from DAN

As of 1/1/20 the Guardian policy is no longer offered to divers age 70 and older.

Preferred and master plans are still available.

Health for Diving

Howard Ratsch — Tue, 26 Nov 2019 11:39:24 GMT

Health for Diving: A Primer on Diabetes

By Robert N. Rossier Dive Training Magazine

https://dtmag.com/thelibrary/health-diving-diabetes/

Health for Diving: A Primer on Diabetes

While this might sound innocuous, the long-term effects of diabetes are dead serious. Diabetes takes more lives than AIDS (acquired immunodeficiency syndrome) and breast cancer combined, claiming one American life every three minutes. Diabetes is a leading cause of blindness, kidney failure, amputations, heart failure and stroke. What’s more, the incidence of diabetes is growing. According to diabetesresearch.org, the number of reported cases of people living with diabetes has jumped nearly 50 percent in the past decade and it now affects more than 29 million Americans. On a global scale, diabetes afflicts more than 380 million people, and the World Health Organization estimates that by 2030, the number of people living with diabetes will more than double. Clearly, diabetes is a growing health risk and one that could affect our ability to dive safely. But, at least for some, the door has been opened for scuba diving with diabetes — that is, if the proper conditions are met and the proper protocols are followed.

Defining Diabetes

Physiology of Diabetes

A Balancing Act

Contributing Factors

Diving with Diabetes

Next, it must be determined that no complications of diabetes exist that may increase the risk of injury while diving. DAN’s guidelines also note that candidates should be 18 years or older (≥16 years if in special training program), with a well-established treatment history and the ability to maintain blood glucose levels efficiently throughout the course of changing demands of daily activities. Those who do not have the ability to control their diabetes (read more here) can be at risk and may not be good candidates for diving. Candidates and divers with diabetes should undergo a mandatory annual medical examination and, if over age 40, should be regularly evaluated for silent cardiovascular disease.

Since the primary risk comes when a diabetic diver experiences a low blood glucose condition, one key to safe diving is ensuring the blood glucose is at minimum safe level — and stable — at the beginning of a dive (see sidebar). The blood glucose must be high enough prior to starting a dive that the dive can be completed without experiencing an unsafe drop in blood glucose. Measuring blood glucose is quick and easy using one of the many blood glucose monitors available on the market today. Continuous glucose monitors (CGMs) are also available to help monitor blood glucose levels and trends.

Food Sense for All

Considerations for Candidates

Glucose Management: Procedures for Diabetic Divers

Safe diving for diabetic divers requires strict protocols, as well as the development and use of good practices and habits. DAN recommends that divers make a general self-assessment of their fitness for diving on the day of the dive, as well as maintaining good hydration throughout the days of diving. Specific protocols* for glucose management on the day of diving include the following:

§ Divers should delay the dive if BG is less than 150 mg dL-1 (8.3 mmol L-1) or greater than 300 mg dL-1 (16.7 mmol L-1).

§ Divers must carry readily accessible oral glucose during all dives and have parenteral glucagon available at the surface.

§ If hypoglycemia is noticed underwater, the diver should surface (with buddy), establish positive buoyancy, ingest glucose and leave the water.

§ Check blood sugar frequently for 12-15 hours after diving to ensure safe levels.

§ In order to establish best practices for future diving, diabetic divers should log all dives and include BG test results and all information pertinent to diabetes management.

§ For more information, contact DAN and consult your physician.

* Divers Alert Network, Guidelines for Diabetes and Recreational Diving, Proceedings Summary | DAN/UHMS Diabetes and Recreational Diving Workshop.

Symptoms of Hypoglycemia

§ Excessive hunger

§ Weakness or dizziness

§ Confusion

§ Unresponsiveness or inappropriate responsiveness

§ Blurred vision

§ Glazed eyes

§ Sudden mood changes

§ Irritability

§ Loss of consciousness or altered state of consciousness

§ Seizures

Glycemic Index and Load

The glycemic index is a measure of how rapidly a food is converted into glucose through digestion. A high glycemic index means a food converts quickly. The glycemic load is a measure of the impact of a typical portion of the food on blood glucose, taking into account the typical portion size. The values shown in the table below are just a few examples to give you an idea of how foods affect blood glucose and some are quite surprising. As the data suggests, even minor adjustments to diet can have a large impact on blood glucose control. Numerous online sources are available to provide values for a broad spectrum of foods.

Diving with redundant air source for recreational divers

Howard Ratsch — Mon, 21 Oct 2019 21:52:42 GMT

https://www.tdisdi.com/diving-redundant-air-source/?utm_source=eNewsletterPro&utm_medium=email&utm_campaign=Do_you_dive_with_redundant_air%3F__5288&fbclid=IwAR1rwdf6ZnwUQR-mFcNi4efgHHQhAW3adYj9EUazsOLwhp6weFLUA1_UuOQ

Thanks to SDI/TDI and Mark Manthey for this article.

Diving with redundant air source for recreational divers

By Mark Manthey

Diving with an alternate air source (octopus) is something all divers do. However, not many recreational divers use a REDUNDANT air source. That is a completely independent air source (second cylinder, first stage, and second stage regulator set). For most recreational diving, your buddy is your redundant air source. However, in the Great Lakes region, where divers often dive below 100 feet in cold water, redundant air sources such as a pony cylinder are common, almost standard equipment for recreational divers.

So, where, when, and why dive with a redundant air source?

Should these dives be considered a technical dive? Now, that’s a great question, but we won’t address that here. Clearly, the ability to bailout of a dive, and to be self-reliant, gives divers in a catastrophic gas loss situation (such as second stage freeflow) more, better and safer options to surface safely without panic, without the assistance of a buddy.

· Depth, due to the longer ascent time. At 130ft or, 40m, assuming a 30ft, or 10m per minute ascent rate, and a 3-minute safety stop, the total ascent time would be about 7 minutes. Depending on the gas loss rate, there may not be enough gas in the cylinder for the diver to safely surface.

· Overhead environments such as a LIMITED penetration wreck dive, or ice diving. (This kind of diving may not require decompression)

Many options are available for diving with a redundant air source;

· Back mounted doubles with a manifold. This configuration is favored by many technical divers. The manifold allows the diver to access the gas in both cylinders from a single regulator, and each cylinder has a first and second stage regulator. It may sound like overkill, but it’s a great setup, and I dive with them as a recreational diver often, on deep dives.

· Sidemount. In recent years, sidemount configurations have gained popularity, and for good reason. Sidemount offers two independent cylinders, and easily accessed valves. Many sidemount divers use two 80cf aluminum cylinders, as they are widely available on nearly any dive boat, offering the diver 160 cubic feet of gas.

· Single cylinder with H-valve. The H valve offers the redundancy of doubles, on a single cylinder. It’s compact and lightweight.

· Pony cylinder. Pony cylinders come in a wide variety of sizes and mounting options. The key is to find the one right for your planned dive. Pony cylinders range from just two or three cubic feet, to 40 cubic feet. A small pony cylinder may be only good for a minute or two for deep dives but should be ok for bailout on shallow dives. In my estimation, its best to get larger pony cylinders. If you’re going to make the investment, you should give yourself the largest margin of safety for the money you spend. Pony cylinders have a variety of mounting options.

Again, you should choose the one right for you. Generally, they are either slung on the left side, or mounted on the right side of the divers’ main cylinder by a mounting bracket. I prefer to sling them. This allows the diver to easily manipulate the valve or hand off the cylinder to another diver if needed. A back mounted pony keeps the cylinder neatly tucked out of the way, and is favored by public safety divers, because it keeps it from dragging through the mud and muck they commonly find themselves in. However, this setup makes it difficult to manipulate the valve if needed.

Diving with redundant air sources offers safer and better options in an emergency, however, there are some issues that should be considered.

1.Plan your dive, dive your plan

First, there is no good reason for running out of air under normal diving conditions. Plan your dive, dive your plan. Use the rule of thirds and calculate a turn pressure that allows you to safely reach your exit point with adequate air pressure remaining. All divers should be in a position to surface with roughly one-third of their remaining gas pressure. Redundant air sources are for emergency use only and should not be used in calculating the depth and duration of your dive. If you need to use your redundant air source, the dive is over, and you’re in bailout mode.

2. Practice using it

Second, if you’re going to dive with a redundant air source, make sure you and your dive buddies are familiar with how to use it, and practice, practice, practice deploying it. Did I mention you should practice deploying, and using, a redundant air source? Ok, good. It is spooky how quickly learning how to deploy a pony becomes second nature. When diving with a pony, for example, I dive with the regulator charged and the valve shut off, to prevent an accidental gas loss. I make sure all my buddies know that if they need to use it, it will only have two or three breaths in the line until I can open the valve. I know some divers that always dive with their pony valves open. It’s not right or wrong, just a preference.

3. Valve shut off

Valve shut down is not a skill generally learned at the recreational level of diving. However, in a situation where a diver is having a catastrophic gas loss, I firmly believe it to be appropriate for the affected valve to be shut down. Shutting down the valve will save the remaining gas in the cylinder, and it could then be used later if needed. This also needs to be planned and practiced, practiced, practiced with buddies. I have had second stage freeflows myself, on occasion, and have assisted several divers with them. The freeflow is almost always caused by second stage icing due to cold water. Once the valve is shut off for a minute or so, the regulator has a chance to thaw, and will function normally again once the valve is turned back on. In my personal preference, I always position the cylinder on my BCD high enough so that I can shut down my own valve. A buddy may also assist with valve shutdown and opening. If the gas in the cylinder is simply allowed to deplete, the diver will lose the ability to power inflate their BCD or drysuit, once they reach the surface. They would then have to remember to orally inflate. This one simple thing could cause an already distressed diver to panic.

In conclusion, diving with redundant air sources allows a diver to mitigate some risk, however, they also come with risks of their own. I believe it is impossible to mitigate one risk without accepting a risk of one sort or another. Every diver must make that decision for themselves.

The Scuba Skills Refresher

Howard Ratsch — Tue, 10 Sep 2019 17:31:17 GMT

thanks to Diver Training Magazine

https://dtmag.com

Keeping It Real: The Scuba Skills Refresher

By Barry & Ruth Guimbellot

HOW MANY TIMES have you thought about going on an exciting dive vacation, only to have something come up that pushes your plans farther into the future? Whatever the reason, your trip gets postponed and before you know it, you’ve been “dry” for a while. If you’ve been away from diving for several months or longer, we highly recommend visiting your local dive center to schedule a scuba refresher course prior to going on a dive trip. Fine-tuning your skills after a hiatus from diving is a wise decision that will help make your return to diving safer and more enjoyable.

Scuba Refresher: Dust the Rust Off

The first step to dusting the rust from your skills is to schedule a scuba refresher course with an instructor at a dive center near you. Your reviewing instructor will help you assess your current status and determine the level of review you’ll need in order to bring your skills up to par. The work needed to fine-tune your skills will depend on a few factors, including your experience level before the hiatus and the length of time you have been away from diving.

A typical scuba diving refresher course has two main sections. One section consists of reviewing the basic safety information you learned when studying for your certification. The second section involves performing basic scuba skills in a confined water setting. With the assistance of your instructor, you will be able to identify and practice the skills necessary for your level of certification. In general, the skills you’ll review in the skill circuit include underwater communication using hand signals, mask clearing, regulator removal, replacement and clearing, buoyancy control and swimming. Your instructor may also encourage you to practice air-sharing techniques often used when handling out-of-air emergencies with a dive buddy.

Underwater Communications

Good communication is essential for an enjoyable, safe dive. Learning appropriate hand signals makes communication with your buddy much easier, avoiding a great deal of frustration. If your memory on basic hand signals is a bit rusty, review them with an instructor or refer to your training materials. Basic hand signals include the OK sign, up/down signal and the out-of-air sign.

Mask Clearing

Nothing is more frustrating than struggling with a leaky mask — even if the reason the mask leaks is that you’re smiling a lot while diving. The skill circuit is the perfect time to practice clearing your mask. To begin, you will need to add water to your mask so you can practice getting it out. Do this by tilting your head slightly down and gently lifting a portion of the skirt away from your face. Allow a small amount of water to enter the mask. With the palm of one hand, push in and down on the top frame to hold it in place as you tilt your head back and exhale through your nose into the mask. The added air displaces the water, forcing it out the bottom of the skirt. When the water is gone, press in on the mask to seal it to your face.

Note: your instructor might show you a couple variations of the mask clearing skill. Use whichever method works best for you.

Regulator Removal/Replacement

If you have not dived in a year or more, how proficient and comfortable will you be at removing and recovering your regulator? This is an important part of any scuba refresher. Many of us are not at ease if our primary air source is unexpectedly dislodged from our mouth. To overcome this fear, practice this skill with your buddy or instructor by your side. First inhale a normal breath, then remove the primary second stage regulator from your mouth and hold in front of you with the mouthpiece facing downward. Immediately begin blowing a small, steady stream of bubbles. Developing the habit of exhaling a tiny stream of bubbles helps remind you not to hold your breath while on scuba, as doing so puts you at risk of injury. Clear the water from the primary second stage by exhaling through the regulator. You can also press the purge button on the front of the regulator to expel water.

The regulator recovery skill is a continuation of the removal/replacement skill. Performing this skill demonstrates that you know how to locate and replace the regulator. Remove the second stage from your mouth and let go of it while continuously exhaling a stream of small bubbles. Begin the sweep by leaning with the right shoulder downward. Allow the regulator hose to swing and hang away from your body. While continuing to slowly exhale, begin a downward sweep with the right arm, fully extending the arm behind you. Next, swing your extended arm out to the side and in front of you. The regulator hose should now be lying across your arm. The second stage should be close to your right hand. With either hand, grasp the regulator, put the mouthpiece in your mouth and immediately clear the regulator of water using either the blast or purge method. Resume breathing normally.

Buoyancy Control

Perfecting buoyancy control takes time and, if you’ve been away from diving for a while, this skill can get rusty. Two tips for better buoyancy include being properly weighted and having good breath control. After practicing this skill, test your ability by hovering in one position. In our example, the diver has lifted his legs and grasps each leg below the knee. If you are correctly weighted and using good breath/buoyancy control, you will be able to hover upright without falling forward or backward.

Swimming

If you haven’t worn fins in a while, it’s a good idea to do some practice laps in a pool. You can do this with just your snorkel gear. It’s also a good idea to do some surface and underwater laps while wearing a full set of scuba gear. You might want to practice managing a leg cramp, too, just in case.

As a reminder, if you experience a “Charley Horse”-type leg cramp of the calf muscle, grasp the fin tip and extend the leg while pulling the toes toward you.

Air Sharing

Being able to share your air supply with another diver could prove to be an important skill in an out-of-air situation. First, get the attention of your buddy by signaling you are out of air. Your buddy will either give you his or her octopus regulator or their primary second stage. If your buddy gives you their primary second stage, they will either start breathing off their octopus or the integrated BC second stage. Practice this skill as both the out-of-air diver and the air donor. In a real-life situation, once you and your buddy each have a supply of air you’ll hold onto each other and slowly start for the surface.

Even if you dive several times a year, a scuba refresher such as practicing this circuit before your trip is a great way to keep your skills sharp. Having proficient skills will make your dive experience safer and a great deal more fun.

For a more in-depth review of these and other skills, visit the Dive Training YouTube channel.

Story and photos by Barry and Ruth Guimbellot

BACK BASICS: EXERCISES TO KEEP YOUR BACK SCUBA-READY

Howard Ratsch — Wed, 28 Aug 2019 12:01:36 GMT

Back Basics: Exercises to Keep Your Back Scuba-Ready

By Dive Training

Low back pain is a very common medical problem, estimated to occur in about two-thirds of adults. Because divers must move around a great deal, climb ladders, lift tanks, and be capable of self-rescue and assisting other divers in the water, back pain can be more than a nuisance for a diver. In some cases it can keep you out of the water.

Back pain can result from a variety of injuries or illnesses. The purpose of this article is not to help you diagnose the cause of your back pain. That task is best left to your physician. What I hope to accomplish here is to recommend exercises intended to minimize problems with back pain associated with the most common musculoskeletal causes. Before you begin any of these exercises, consult your physician or physical therapist.

Flexibility Training

The fundamental underlying principle is that it helps strengthen and improve the flexibility in your back, stomach, hips and thighs. It is important to balance strength and flexibility. For instance, if you exercise the hamstring muscles in your legs in such a way that they become tight (inflexible), the mere act of bending over may cause you to suffer a back injury. A back exercise program should be maintained on a regular schedule — at least every other day for starters and working up to twice each day. If you don’t keep up the program, and allow your muscles to become deconditioned and less flexible, then you will lose all the advantage you have obtained by stretching and exercising.

Begin each exercise routine slowly, with gradual stretching and lighter loads leading to more vigorous stretching and heavier loads. When you lift a load or exert, you should exhale. Inhale during the rest period between exertions. If you find yourself holding your breath while straining to perform an exercise, your breathing pattern is backwards.

The following are exercises and stretches to relieve back pain. Dress in loose-fitting, comfortable clothing. Equipment you’ll need: an exercise mat or beach towel, a chair. Repeat each exercise from five to 10 times:

Single knee-to-chest stretch – Lie on the floor faceup. Keeping one leg straight and your head against the floor, bend the knee of the opposite leg and pull the knee to your chest, using both hands locked behind the knee. You should feel your hamstring and hip stretch. Hold the stretch for 60 seconds, then pull your leg (still bent at the knee) out from the midline of the body, so that you feel a stretching sensation on the inside of your thigh. Hold this position for 30 seconds. Return your leg slowly to the floor and repeat this exercise using the other leg.

Double knee-to-chest stretch – Lie on the floor faceup. Bend both knees at the same time and pull both knees to the chest, using both hands locked behind the knees. Hold the stretch for 60 seconds, then pull your legs apart out from the midline of the body, so that you feel a stretching sensation on the inside of your thighs. Hold this position for 30 seconds.

Prone back extension stretch – Lie on the floor facedown with hands held against the sides of the body or on the forehead. Gently raise the head and shoulders from the floor and hold for a few seconds. If this is too difficult, place your hands on the floor near your head so that you can push up by straightening your arms. Keep your hips on the floor.

Standing back extension – Stand with the feet slightly wider than shoulder-width apart to maintain balance. Place your hands on your hips or against your lower back and gently bend backward at the waist. Hold this position for a few seconds.

Kneeling back arch (“cat” arch) – Kneel on hands and knees with arms forward of the head, palms on the floor. Tuck down the chin and arch your back upwards, while slowly leaning back on your heels and dropping your shoulders toward the floor. Hold for 60 seconds.

Standing hamstring stretch – Stand in front of a chair. Place one straightened leg on the seat of the chair. Gently stretch the hamstring of the straightened leg by slowly bending the other (balancing) leg at the knee. Try to hold the stretch for 30 seconds. Repeat using the other leg.

Standing calf stretch – Lean forward against a wall with both palms on the wall, heels flat against the floor. Place one foot forward to isolate the back leg, then lean until you feel a stretch in your calf muscles. Hold for 30 seconds. Repeat using the other leg.

Side-bend stretch – Stand straight, then bend at the waist to the side sliding the arm down the leg. Release the stretch and repeat to the opposite side.

Targeting Muscle Groups

The following exercises help strengthen different muscle groups related to back health:

Wall slide (back, hips and legs) – Stand with your back against a flat, smooth wall surface with your feet shoulder-width apart. Keeping your back against the wall, bend your knees toward a squatting position until your knees are bent to a right angle (90 degrees). Don’t squat beyond this position. Hold this position for a few seconds, and then slide back up to a standing position. The arms can be held at the sides or straight out in front for balance.

Prone leg raises (back and hips) – Lie on the floor facedown with your arms at your sides. Keeping one leg pressed against the floor, tighten the muscles in the other leg and raise it up a few inches for a count of 10, then lower it back to the floor. Keep your hips against the floor. Repeat this exercise for the other leg. A variation of this exercise is to place your arms extended in front of your head and raise the arm opposite the raised leg (e.g., left leg and right arm) at the same time.

Standing back leg swing (back and hips) – Stand behind a chair with your hands on the back of the chair. Keep one leg straight with foot planted on the floor while you raise the other leg backwards. Lower the leg slowly and then repeat the exercise with the other leg.

Supine leg raises (stomach and hips) – Lie on the floor faceup with your arms at your sides. Keeping one leg pressed against the floor, tighten the muscles in the other leg and lift it straight up 6-12 inches (15-30 cm) for a count of 10, then lower it back to the floor. Repeat this exercise using the other leg. You should feel a pulling sensation in the hamstring muscles of the lifted leg.

Sitting leg lift (stomach and hips) – Sit upright in a chair and lift one leg straight up to a position where you have a 90-degree angle at the waist, while keeping the other leg straight and lifted just a few inches off the floor. Repeat this exercise for the other leg.

Kneeling leg lifts (hamstrings, lower back and buttocks) – Kneel on the floor with your arms at shoulder-height for balance. Pull in one knee to your chest, then extend that leg straight behind you and lift it up slightly. Hold for 10 seconds. Repeat with the other leg.

Semi sit-ups (stomach “crunch”) – Lie on the floor faceup with knees bent and feet flat on the floor. Raise your head and shoulders slowly off the floor and reach toward your knees with your hands. Tighten the abdominal muscles. Hold the “up” position for two seconds, then release and slowly lie back down.

Back pain may be a symptom of a potentially serious situation. Inform your physician if your pain is accompanied by fevers, chills, unintended weight loss, difficulty with urination or bowel movement, pain or a tingling sensation in the legs or feet, or loss of circulation in the legs or feet.

To prevent low back pain, avoid risks such as heavy lifting (particularly while bending forward at the waist), sudden or forceful twisting of the torso, extreme body blows or vibration, jumps from heights, obesity and poor physical condition.

When Not to Exercise

Most therapists agree that it is not useful to begin exercises during the acute period when you have just suffered a back injury or have begun to experience pain. It is best to wait until the pain (and perhaps inflammation) has begun to subside, usually from seven to 10 days from the time that the pain has significantly improved. If you are controlling your back pain with pain medication, you must be particularly careful to wait to begin exercises until instructed by your physician or therapist.

Back-Saving Tips for Divers

Specific prevention measures for divers include:

When lifting any heavy objects, bend at the knees, not forward at the waist. This is particularly relevant when handling tanks and heavy luggage.

When donning a tank, let someone help you. Some persons like to lift a tank up over the head to slide it down their back so that they can slip their arms into the attached buoyancy compensator (BC). This puts extra strain on the back and neck, risks dropping the tank, and is much less stable than sitting or standing and having the tank carried into position by another person.

When wearing a tank, move very carefully when walking, particularly on a boat. It’s easy to lose your balance and fall or wrench your back. Try not to bend forward more than is necessary to maintain balance. Always hold on to something to maintain stability.

Be very careful ascending and descending ladders, particularly when wearing a tank.

Do a few stretching exercises before donning dive equipment before each dive.

Avoid sitting for prolonged periods. This is the anatomical position that is least favorable for low back strain, especially for those with chronic back problems.

By Paul M. Auerbach, M.D.

Scuba Diving for Seniors

Howard Ratsch — Thu, 18 Jul 2019 17:23:06 GMT

https://dtmag.com/thelibrary/divers-of-a-certain-age-scuba-diving-for-seniors/

Thanks to Karen and Ian Stewart of Dive Training Magazine for the article.

Physical Fitness and Our Growing Waistlines

No matter your diving age, fitness is important. Just consider some of the activities you will need to do while diving. Can you do a surface swim in your equipment if you come up away from the boat? Can you physically get yourself into or out of the water before or after your dive? Could you help your buddy if they needed it? As we age our physical abilities decline and we may not exercise regularly or adequately. And like the rest of the country our waistline may be growing. Did you know that the average person gains about 3 pounds (1.4 kg) per decade starting at age 20? Being overweight may not itself be a restriction to diving but it may indicate a lack of physical fitness and certainly can put you at greater risk for cardiac incidents.

Being in poor physical shape as well as being overweight has also been shown to affect bubble formation after diving. You may remember from your training that bubble formation can be an indicator of your susceptibility to decompression sickness. In a recent study (J Appl Physiol. 2002 Oct; 93(4):1349-56. Ascent rate, age, maximal oxygen uptake, adiposity, and circulating venous bubbles after diving. Carturan D, Boussuges A, Vanuxem P, Bar-Hen A, Burnet H, Gardette B.), scientists found that “Younger, slimmer, or aerobically fitter divers produced fewer bubbles compared with older, fatter, or poorly physically fit divers.”

Being overweight can also put you at risk for Type 2 diabetes (noninsulin-dependent diabetes). Diabetes is usually considered to be a contraindication to diving by Divers Alert Network (DAN).

Is Age a Barrier to Physical Fitness?

We commonly assume that the older we get, the less we will benefit from exercise. However researchers have found that when it comes to improving the strength or endurance of our muscles, age is not a barrier. The cause of age-related differences in fitness appears to be the cumulative effects of our lifestyle choices. We choose to do less, and our bodies adapt. No matter what your age, if you reverse this downward trend you will see that your physical fitness and health will improve compared with others of the same age. Maintain your activity level, and fitness becomes easier to keep over time.

So how do we determine whether we are physically fit enough to do diving? Neal W. Pollock, the research director at DAN, in a 2007 article on fitness and diving, discussed measuring physical fitness by calculating aerobic capacity. Aerobic capacity testing is most commonly completed with treadmill running or stationary cycling. Pollock recommends that a diver be able to maintain a capacity of 10 MET (metabolic equivalent) or greater. A MET is the amount of energy being burned when a body is at rest, with the normal MET in a healthy population ranging from 5 to 25. A diver under relatively calm dive conditions can dive safely with a capacity of only 7 MET. But add in any challenges and that capacity might not be enough.

For more information on assessing your physical fitness to dive, see Alex Brylske’s “Are You Fit to Dive” article in the September 2010 issue of Dive Training.

My Aging Heart

Diseases of the heart and blood vessels are the leading cause of death in the United States and according to DAN one of the most common causes of fatal diving accidents. As we age the prevalence of cardiovascular diseases increases. From DAN’s 2008 Annual Diving Report it was reported that the 2006 collection of data included 75 scuba fatalities investigated by DAN. Of these cases, 38 percent were attributed to heart disease, with the majority of the victims being classified as overweight or obese by body mass index. Annual death rates for insured DAN members were stable during 2000-2006, with a mean of 16.4 deaths per 100,000 members. Fatality rates increased dramatically with age. Among divers 15-25 years of age, the fatality rate was less than 10 per 100,000 members but increased to 30 per 100,000 among divers 65 years of age and older.

High blood pressure is another factor to consider in assessing your fitness to dive. The average 60-year-old American male has a blood pressure of 140/90; 120/70 is considered normal. Chronic hypertension is associated with damage to the heart, kidneys and an increased risk of stroke. Antihypertensive medications, however, can help reduce the risk of serious illness. Most antihypertensive medications are compatible with diving as long as the side effects experienced by the diver are minimal and their performance in the water is not significantly compromised.

Physical activity on a regular basis will certainly help improve cardiovascular function. Make sure that you discuss any new physical program with your doctor before proceeding.

Is That In Focus?

As a photographer, one of the things I really notice with aging is the change in vision. My arms are no longer long enough for my gauges and seeing pygmy seahorses even with a viewfinder is more than difficult. As we get older, the closest point at which we can focus moves away from the eye about 0.4 inches (1 cm) per year. By the time we get into our 40s most people will be having some trouble reading. At this point the drug store reading glasses become our friend. Underwater you may be able to put your gauges on a retractable holder so you can pull them out to arm’s length or you may opt for corrective lenses in your mask. Several inexpensive options are available at your local dive store. These can include lens spots, lens bonded into your mask or even ones that adhere to your mask by water surface tension. And for spotting small stuff, we also carry an underwater magnifying glass.

Did He Say Go Right or Left?

As we age our hearing becomes less acute and for many of us this begins to affect our daily lives. The National Institutes of Health predicts that an estimated one-third of people in the United States between the ages of 65 and 75 and close to one-half of those older than 75 have some degree of hearing loss.

In diving hearing loss can pose a problem, especially during the dive briefing. You can miss important information about direction, timing, depth, conditions and safety factors. There are a number of easy steps to overcome this. Be sure to inform the divemaster that you are hard of hearing and may need for him to speak up or repeat things. Always confirm the dive plan with your buddy before entering the water.

Picking the Right Diving and the Right Location

As well as staying physically fit and maintaining a good diet, we can also alter our diving styles and locations as we age.

Both of us enjoy a “slow” style of diving not only because we are photographers but also because it helps us to conserve air and actually allows us to see more critters. We now try to find those dive operations that don’t enforce staying with the divemaster in a larger group. Many live-aboard operations fit this style of diving by giving you and your buddy the freedom to set your own dive plan and having the added benefit of limited gear handling. If you are diving with a day operation, it is important that you make sure that they know you and your buddy may drop behind.

As we have gotten older our choice of destinations has also altered. Places that offer good visibility, warmer waters, less current and easier shore access with shorter swims are more important to us now. We also have reduced the number of dives we do in a day. Our five-dives-a-day regime has given way to three or four dives, with more time for relaxing and socializing.

The Right Equipment

As with any sport, matching the right equipment to your physical needs is of great importance. Here are a few tips on how to synch your equipment with your aging diving aspirations:

Lighten the load. As we get older we lose strength and stamina. You can overcome this somewhat by reducing the weight of your dive gear. If your diving environments have shifted to less demanding conditions then you may not need a buoyancy compensator (BC) with as much lift capacity as before. Manufacturers have introduced many new styles that have reduced weight, are easier to carry and take up less space when traveling on a dive trip.

Smaller fins can also help. Stiffer, longer fins may be a thing of the past. Instead, like us, you may opt for some shorter and lighter full-footed fins. They are easier to pack, easy to put on and take off and don’t require a huge amount of energy to pump.

Lengthen your straps. Reduced flexibility comes with age. It gets harder to reach down and adjust those fins. Try looking for gear that makes it easier to deal with that lack of flexibility. Get fins that have large pull-tabs and that are easy to adjust. Look for options on wet suits that allow you to easily get into the suit — this may include extra zippers on the legs and arms.

Grow your gauges. As mentioned earlier it may be getting harder to see those gauges. Look for gauges and watches that have larger dials and are intuitive to read. An easy-to-read gauge will reduce a lot of unnecessary anxiety when checking air supply and time.

Roll your bags. Our bags seem to get heavier every year. Over the years we have reduced our footprint, lightened our load and added wheels. There are a number of choices out there today for wheeled duffels of all shapes and sizes. These bags make it a breeze for getting your dive gear from A to B.

Keep the core warm. Studies have found that the body’s response to cold changes significantly over a lifetime, with older people less able to maintain their core temperature at a given cold exposure than young people. You can help overcome this by staying warm, before, during and after the dive. Make sure you have the proper clothing to keep you warm before getting suited up for the dive (a hat helps). Make sure you have enough thermal protection to get you comfortably through the dive (a hood helps) and finally make sure you have clothes that will keep you warm after the dive.

The Incentive

There are challenges to diving as you age but there are also a number of psychological and physical benefits associated with continuing to dive.

Although diving may not be something that you do every day it can be an incentive to staying in good physical shape. And by being in good physical shape through regular aerobic activity such as walking, jogging, biking or swimming as well as muscle-strengthening exercises, we are more able to continue to perform the routine tasks of daily life. Stronger muscles also help to reduce the risk of falling and fracturing bones. Physical activity helps in reducing the risk of coronary heart disease as well as developing high blood pressure, colon cancer and diabetes. Studies have also indicated that physical activity is linked to improvements in positive psychological states such as confidence, well-being, mental energy and personal image. Although there is still much debate as to the reasons for these benefits, the overwhelming evidence supports the relationship between positive mental health and physical activity.

Diving can also be a very social sport. It is a great way to travel and meet new friends. Participation in social activities as well as physical activity help to reduce the severity or chances of developing disorders such as anxiety and depression while reducing the deterioration of cognitive functions associated with aging.

Your senior status may mean you actually have more time to devote to leisure activities like traveling and diving. Certainly diving can be enjoyed through your senior years. So stay active, eat healthy and get out there and dive.

11 Tips For Safe Diving

Chris Hardham — Wed, 29 May 2019 14:58:21 GMT

11 Tips For Safe Diving

by Torben Lonne | 1 comment

Is scuba diving a dangerous sport? No, it’s not.

In fact, diving is considered to be safer than many other more conventional sports.

Despite what sensationalist news headlines suggest, the incidence of diving accidents is far less frequent than you might imagine.

And if you know your training and how to be a safe diver, the risks are minimal.

In order to qualify as a scuba diver you have to pass a medical clearance, and complete both theoretical and practical exams. Add to this the fact that modern equipment is both reliable and high tech, and you have all the ingredients for a safe sport.

PADI alone certifies nearly one million divers every year. So one can only imagine how many qualified divers there are out there. And yet, out of those millions, every year only approximately 1000 divers worldwide need decompression therapy.

It is true that a few scuba divers do experience accidents – some of them fatal. However, most of these are due to carelessness on the part of the diver, or overconfidence.

So here are 11 tips for all divers to keep in mind to ensure that they are diving safely.

Plan, plan, plan.

You’ve heard it before and I’ll say it again: plan the dive, and dive the plan. Planning a dive is vital when it comes to safety. Although this is particularly important for difficult or deep dives, it still applies to every dive that you do.

Verify the safety of your equipment.

Check your equipment a week before you plan to dive. Make sure everything has been serviced and maintained properly. Remember to check the batteries for your dive computer and underwater torch. When you arrive at your destination and are ready to kit up, you need to check that your equipment is working properly. If you are diving with a buddy, then check his equipment too and ask him to check all your gear as well.

Test new equipment in a controlled environment

It’s natural to be excited to test out a new piece of equipment. However, in the interests of safety it is always best to first test new equipment in controlled conditions. Your best option is to test it in a swimming pool. If that is not possible, then make sure that you use it during an easy shallow dive first. You don’t want to have to struggle with new equipment on a deeper dive.

Make sure you are ready to dive.

In addition to your equipment, your body needs to be ready to dive. If you are feeling ill or otherwise unprepared to dive: listen to the messages that your body is sending you. It’s more important to miss a dive because you’re not feeling up to it, than it is to take risks.

Find out about the current conditions (no pun intended!)

Before you dive you need to have an accurate assessment of the sea conditions. The surface conditions might affect the safety of boat launches, apart from anything else. The water temperature is important because that will determine what type of wetsuit to wear. Being too cold or too hot when you dive will be uncomfortable and might compromise your safety. Find out what the underwater conditions are. If there is extremely poor visibility, very strong currents, or other potentially problematic conditions then it might be safer to postpone the dive to another day.

Dive within your limits

Under no circumstances should you dive beyond your limits. If you are only qualified to dive to a certain depth, then ensure that the dive plan does not exceed that depth. This also applies to specialized diving that requires additional certification. Do no attempt something like cave diving unless you have qualified by completing the relevant certification. There is no place for ego or bravado here.

An alert diver is a safe diver

There is a reason why divers are cautioned not to drink alcohol for 24 hours before diving. You don’t want to have alcohol in your system when you dive because you need to be alert. If you are feeling hungover or very tired, it is not advisable to dive. You need to be alert and focused in order to dive safely.

Consult your gauges regularly

This might sound obvious but you’ll be surprised how many accidents occur because divers don’t adhere to this basic rule. If you are diving with a buddy, then let him know when you reach half your tank, and again when you reach your reserve. You and your buddy should from time to time ask each other how much air the other has left.

Know the dive signals

Marine life enthusiasts often get excited about learning the signals for different species. However, the most important hand signals are those pertaining to safety. Make sure that both you and your buddy understand a comprehensive array of signals. Not being able to convey messages accurately and understand each other underwater poses a potential safety risk.

Avoid colliding with a boat

Make sure that you always carry a marker buoy with you. Do not assume that boats can see you! Plan your ascent so that it is as close to your boat as possible. When you do your safety stop, make sure that you are at the recommended depth. If you don’t control your depth and buoyancy properly then you run the risk of doing your safety stop at propeller depth. (True story.)

Take responsibility

Even if you are diving with a buddy or even a team, you need to take responsibility for your own safety. It is up to you to ensure that you follow everything that you have learnt about safe diving. In this way you will avoid endangering yourself, or the other divers accompanying you on the dive.

Source: DIVE.in

5 Tips for the Best Safety Stop

Chris Hardham — Sun, 31 Mar 2019 21:35:00 GMT

5 Tips for the Best Safety Stop

By Travis Marshall April 12, 2017

Reposted from ScubaDiving.com website

Every dive should end with a safety stop. But being close to the surface makes buoyancy a challenge, and without the right technique, you might find yourself ascending unintentionally. Here are five tips for making safety stops look easy.

5 Tips for a perfect safety stop.

1. SLOW ASCENT Keep an eye on your computer or depth gauge to make sure you ascend no faster than 30 feet per minute. Remember to vent expanding air from your BC as you go, and always send up a surface marker if you’re ascending away from your boat.

2. PROPER POSITIONING Once at 15 feet, position yourself head-up and keep your depth gauge at chest level so your torso stays at the right depth.

3. STEADY AS SHE GOES If you’re holding a down line attached to boat, grab the line loosely with one hand, with your arm outstretched to prevent the line from pulling you up and down.

Always time your safety stop.

4. TIME IT Every diver should time his or her own safety stop — don’t rely on another diver.

5. SWIM SLOWLY Divers sometimes think once the safety stop is over, they can fin to the boat as fast as they want. But the final 15 feet are the most dangerous part of the water column for lung-overexpansion injuries. Ascend the final 15 feet at the same, slow 30-feet-per-minute rate.

Challenging The “Rules” of Scuba Diving: Because Not Everything is Black and White

Sat, 29 Dec 2018 16:31:26 GMT

At first glance, these might seem like black-and-white concepts. Except, guess what? They’re not. At least not entirely.

Rulemaking 101

Norms — and the rules that often evolve from them — provide order in society. These are some of the reasons why most people, most of the time, conform to social norms and abide by certain rules.

Let’s examine some commonly accepted scuba rules regarding equipment and dive practices that might be worthy of bending. If nothing else, they’re worth pondering.

Equipment-Related Rules

Always wear a snorkel.

Guilherme Garcia photo

Never put your mask on your forehead.

No gloves allowed.

Always turn the tank valve back a quarter- or half-turn.

Before entering the water, make sure you tank valve is turned all the way on.
Guilherme Garcia photo

This one’s been around forever. And it’s wrong. Don’t do this. Instead, always turn the valve all the way on and leave it that way. Do not turn it back at all.

Ruling How We Dive

Never dive alone. Always dive with a buddy.

Always do your deepest dive first.

By the 1980s ‘deep dive first’ was growing beyond a recommendation.

Always end the dive with at least 500 psi remaining in your tank.

Never, ever make contact with the bottom.

In some instances, making contact with the bottom is considered an acceptable practice.
Guilherme Garcia photo

If you haven’t wanted to burn me at the stake by now, here goes. Over the years we have occasionally published photos of divers kneeling on the bottom. This usually results in a flurry of reader letters calling Dive Training out for promoting bad diving practices. Most recently, in the July/August issue, we ran cover photos that feature two divers standing/kneeling on a sandy bottom while on a shark dive at the famous “Tiger Beach” dive site off Grand Bahama Island. I am one of the divers pictured in the photo. I’m not sure where or when the “never touch the bottom” rule got started, but I can assure you there are several instances in which kneeling in the sand is an accepted practice. Tiger Beach is a perfect example. The site is shallow (less than 30 feet [10 m]), there’s usually a moderate current running — and the water is filled with sharks. For these reasons, attempting to stay neutrally buoyant, kicking hard against a current while hovering a few feet off the seafloor and keeping an eye on the sharks would be impractical — and potentially dangerous. Here, kneeling in the sand is the best practice. Dive operators in other parts of the Bahamas, Fiji, Tahiti, the Maldives and other popular dive destinations follow this practice.

Always breathe continuously. Never hold your breath.

As I mentioned earlier, this is arguably the “number one rule” of scuba because breath holding while scuba diving can lead to serious injury, even death. However, there’s a however here.

MaFelipe photo

A Question for You

Courtesy of Dive Training Magazine.

Health consideration in diving

Mon, 01 Oct 2018 23:08:59 GMT

Hello all,

With the recent closures of area beaches from possible Red Tide and the issues of Green Algae, we need to take consideration as to possible health issues when diving. Here is a 2011 article from Alert Diver Magazine on health considerations when diving.

Microbial Hazards

By Michael Miller, Ph.D., and Petar Denoble

A threat to scuba divers?

The hazard of human infection for those exposed to the sea has been known for a long time, but the public is becoming more aware of it as new evidence of the oceans' rapidly deteriorating health emerges. Even the most pristine seawaters are inhabited by large numbers of microbes.

Most of them are harmless to humans, but some, like the vibrio species, can make people sick or even kill them. Increased pollution, warming and acidification of the oceans, all of which cause the death and extinction of fish and coral species, also promote the growth of indigenous microbes and increase the concentrations of terrestrial pathogens. Pollution and microbial hazards are greatest in coastal waters; unfortunately, this is where most recreational activities occur.

Routes of infection

Indigenous and introduced microbes may cause illness in humans either by infection or indirectly by intoxication. The sheer volume of seawater and its constant movement usually dilute foreign microbes below concentrations necessary for human infection. But there are many conditions when critical concentrations may be reached or when the threshold for infection in an individual is lowered. The greatest risk for human health comes from consumption of seafood.

Human potential for contracting diseases from pathogens in the marine environment depends on exposure time, the virulence of the pathogens and the susceptibility of the individual. Microbes generally infect humans through ingestion, inhalation or mucous-membrane exposure (naturally occurring or in wounds). Microbes can infect through injured skin, the ears and the mucosa of the mouth, eyes and nose. Infections may also result from swallowing water. Nonfatal drowning in marine environments brings seawater into the lungs and can result in pneumonia. Some hazards like aerosolized bacteria, generated in coastal environments by wave activity, can transmit algal toxins to humans and cause viruses to become airborne. This type of hazard is less likely to cause illness in divers than swimmers, thanks to masks and regulators.

Risk of direct infection by microbes from seawater is very small. However, the risk increases significantly in warm, brackish waters, in waters proximate to sewage and run-off inlets, at places of animal access and at populated beaches Divers may acquire dive-specific infectious diseases from exposure to the marine environment or as a result of close contact with other people and their dive equipment. If equipment is not properly cleaned, dried and stored after use, colonies can grow and microbes can reach sufficient numbers to infect users. Paradoxically, efforts to protect equipment from the corrosive effect of sea salt may also result in unwanted risks to divers' health.

Communal culprits

Communal rinse tanks have been shown to concentrate bacteria, so rinse
gear that comes in contact with skin — and especially mucous membranes
— under running water when possible.

Most dive operations offer some kind of communal fresh-water tank for the postdive rinsing of equipment. Generally there are tanks for rinsing wetsuits, masks, boots, regulators and buoyancy compensation devices (BCDs) along with separate tanks for photo equipment. Despite the best of intentions, such a system may demonstrate more care for camera equipment than for human health. The volume of dive gear passing through rinse tanks in a day may significantly exceed the volume of water in it. Because of the inequity, rinse tanks become the means for collecting and concentrating microbes from all users, creating the potential for spreading infections among them.

In 2007, a research team under Michael Miller of West Virginia University embarked on a study to sample water from communal rinse tanks and check it for the presence of bacteria. The first test was conducted at a popular Caribbean dive destination. For four days, the team collected daily water samples from communal rinse tanks after they were first filled in the morning and again several times throughout the day. They divided small amounts of the water samples onto agar plates and subsequently observed bacterial growth of different morphologies and swimming patterns. They did not attempt to identify the bacteria during this phase of the study and, therefore, did not determine if any were harmful to humans. This preliminary research simply confirmed the possibility of significant bacterial presence in rinse tanks.

Several months later, a similar study was undertaken at a dive facility on another Caribbean island. The operation's two boats each had two rinse tanks: one for wetsuits and BCDs and another for masks and regulators. The operator fully cooperated with the study; for five days the wetsuit tanks were drained each morning, and one of them was cleaned with bleach before they were refilled. The team took water samples from both tanks at that point and again at multiple times throughout the day.

Notably, this facility also allowed the sampling of water from the pipes used to fill the tanks, an opportunity not previously afforded the team. Tests showed the water used to fill the tanks was free of bacteria, nor were bacteria detected in either tank immediately after they were filled in the morning. However, by the afternoon all three tanks contained a lot of bacteria of many different types. Precleaning with bleach did not impact bacterial contamination. The two mask rinse tanks on the boats were also sampled, and both of these contained very high levels of various, unidentified types of bacteria. The time pattern of the findings indicated the bacteria were rinsed off of the diving equipment, but it remained unknown whether they originated from the sea or from divers as well as if they were pathogenic.

Finding the answer

Public health officials measure levels of certain species of bacteria to evaluate the risks to humans in many popular recreation areas.

In June 2008, the team performed a third study with the aim of identifying bacteria in rinse tanks along with their source. The study was done at yet another Caribbean dive resort. Water samples were collected from the hose used to fill a communal rinse tank, the rinse tank itself, buckets on the boats in which masks were rinsed and stored, several dive sites in the ocean at various depths and, finally, ocean water near shore at the dive facility. Again, the water used to fill the rinse tanks was found to be safe. But this time the bacteria that developed throughout the day were identified, confirming that some likely originated from the ocean and others from the divers themselves.

None of the identified bacteria would be considered overt human pathogens, but some are considered opportunistic pathogens: They could infect individuals with compromised immune systems or may infect open wounds. Bacteria identified in the communal rinse tanks are generally associated with unsanitary conditions. Where these bacteria are present, other pathogenic bacteria may occasionally occur. The scope of the study did not include checking for viruses usually found along with bacteria that may cause serious diseases.

In the eye of the infected

In March 2006, a group of 27 health-care providers attended a conference at a dive resort in the South Pacific. On the second day of diving, two divers reported eye problems, and over the next few days 13 divers (roughly half of the group) were diagnosed with conjunctivitis, an inflammation of the eye. It is characterized by the sensation of a foreign body in the eye, redness of the mucosa and possible discharge. Conjunctivitis of viral or bacterial origin spreads easily from person to person through close contact. There was an outbreak of conjunctivitis among the local population, but the divers did not have much contact with them.

Two physicians from the group investigated the spread of the conjunctivitis among the divers. They concluded the conjunctivitis originated from a divemaster who had an eye infection prior to the diver outbreak. The divemaster placed his mask in a communal container of diving masks, which apparently became the means by which conjunctivitis was spread among the divers. Only divers who used this tank were infected. Those who did not use the tank were not infected despite close contact with those who were.

To prevent further spread of infection, divers used bleach and detergent for mask cleaning. Affected divers received antibiotic drops and ointments and were healed in the next several days. One diver manifested symptoms after returning home. This case study demonstrated that disease can be spread among divers using communal rinse and storage containers. Conjunctivitis is a disease with short delay from infection to symptom manifestation, which made it possible to identify the source of infection. Other infections may have been transmitted by the same means, but due to longer periods of incubation as well as occurrences after the divers returned home, the link to communal tank was missed.

Based on the lack of reports, the risk of infection by means of communal rinse tanks appears negligible, however, it's possible divers incorrectly attribute such infections to other sources. Miller's findings and the report of the conjunctivitis outbreak indicate communal rinse tanks may serve as avenues of infection transmission between divers. When it comes to rinsing dive equipment in direct contact with divers' skin and mucous membranes, such as masks and regulators, instead of using communal rinse tanks, divers are advised to clean gear using disinfectants under running water.

Other areas of consideration

Besides rinse tanks, there are at least three additional areas in which infections may spread among divers: the common, the rare but dangerous and the feared but unlikely. The most common infections reported in diving are otitis externa (swimmer's ear) and skin infections (impetigo and others). Fortunately, these can be easily prevented, diagnosed and successfully treated.

On the other hand, diving or swimming with an open wound may result in a rare, but often fatal, infection with Vibrio vulnificus, an opportunistic pathogen commonly found in warm coastal waters. The Centers for Disease Control and Prevention receive approximately 150 reports each year of people infected with V. vulnificus, most by eating oysters and a few through open wounds.

Some divers fear sinusitis and cystitis (bladder infection). Indeed, swimmer's sinusitis has disrupted the careers of many aspiring athletes. However, it is most often caused not by microbial infections but by chemical irritation from chlorine used to disinfect pool water. It does not occur in ocean swimming. Indeed, some people with chronic sinusitis maintain that swimming in the sea and flooding their sinuses with salt water helps, a notion seemingly supported by an increasing number of ear, nose and throat physicians who advise patients to use saline sinus rinses to relieve nasal and sinus congestion. However, it's important to remember that the intentional or inadvertent introduction of seawater into the sinuses could cause infection if the introduced water is loaded with a sufficient number of pathogenic bacteria or viruses. It is difficult to come by any such cases in conventional medicine literature.

The effect of swimming on cystitis in women is a popular topic of discussion in the media. The prevalence of cystitis is very high, and in many cases it is recurrent. Each occurrence often is the result of infection by a new causative microbe. Chemical irritation from chlorinated water or the prolonged wearing of a wet swimsuit may enhance the recurrence of cystitis, regardless of the bacterial contamination of fresh or salt water. When it comes to cystitis, it may be a predisposition rather than a specific causation that affects its occurrence.

Putting it in perspective

While it seems there are many microbial hazards in the sea, the true risk of serious infection to divers seems negligible. Most infections that may be occurring among beachgoers, swimmers and divers probably manifest as diarrhea, but that is so common among travelers it is rarely linked to seawater. The two most common infections in divers are ear and skin infections.

To mitigate risks of infection while diving, regularly clean and disinfect equipment, avoid polluted waters, never dive with open wounds (including tooth extractions) or sores, never rinse your mouth or sinus cavities with seawater, keep your ears dry, avoid prolonged wearing of wet clothing and shower after diving. Divers with an acute infection such as a common cold, conjunctivitis, skin infection or gastroenteritis are not fit to dive and must take precautions not to infect others.

Beach Bacteria

Waterborne disease outbreaks (WBDO) have been reported in people bathing in pools and rivers but not among seaside beachgoers. However, due to presence of the diarrhea-causing microbes on seaside beaches, epidemiologists assume that cases of gastroenteritis resulting from exposure to marine pathogens must be common, too. The summertime increase in occurences of gastroenteritis in coastal states indicates a possible role of beaches in disease transmission.

In 2009 and 2010, scientists discovered methicilin-resistant staphylococcus aureus (MRSA) in the sand of many beaches on both the West and East coasts. MRSA causes intrahospital infections with a high mortality rate due to its resistance to many antibiotics. MRSA also occurs outside of hospitals, but the source of infection is not known. Seasonal increases in MRSA infections coinciding with times of increased beach use may indicate beaches are a possible means of MRSA transmission.

Clean and Sanitize Your Dive Gear

By Daryl F. Stanga, HM1/SCW/DV, U.S. Navy

Although the risk is considered to be very small, second stages and mouthpieces could transmit disease. Divers are encouraged to disinfect equipment properly.

Commercial products designed for cleaning dive gear are widely available. Make sure to choose a cleaning agent that does not contain hydrocarbons. If in doubt about a product's usability on dive gear, consult the equipment manufacturer for recommendations.

To clean scuba regulators, use a scrub brush to remove any gross contamination such as mud, dirt, sand, seaweed or saliva from the regulator. Rinse thoroughly with fresh water, then spray a liberal coat of the chosen cleaning agent on and into the mouthpiece and second stage until all surfaces are wet.

Let stand for 10 minutes. If the solution appears to be drying, apply more to keep the regulator wet for the full 10 minutes. After 10 minutes, rinse with clean, fresh water or under running potable water.

If several regulators need to be sanitized at the same time, or if you prefer immersion to clean the equipment, regulators may be immersed in the disinfectant solution for 10 minutes and then rinsed in fresh water.

Use the same procedure to sanitize snorkels and the oral inflation tubes of BCDs. To clean the BCD thoroughly, pour several ounces of the solution into the bladder and agitate for 10 minutes. Then empty the bladder and rinse with fresh water.

Before reassembling, allow the BCD to air dry.

Public Health Policy

From a public health perspective, monitoring popular recreational areas for various indicators is one of the major steps taken in risk reduction. There were more than 24,000 beach closures and advisories in 2010, the second-highest number on record. The majority of these were due to the presence of bacteria. Scientists and public-health officials rely on several factors to determine whether risk of infection is elevated in a particular area.

Unsurprisingly, the presence of sewage is correlated with elevated infection rates. Gastroenteritis and respiratory illness in particular increase with the degree of site pollution. Pollution with sewage is generally assessed by monitoring the presence of enterococci bacteria.
High swimmer density is a second factor shown to increase infection risk. Elevated numbers of minor ear and skin infections from human-shed bacteria are observed where swimmer density is high. Skin granulomas from Mycobacterium marinum have also been observed. Staphylococcus aureus levels have been proposed as indicators of exposure.
Eutrophication, the increased abundance of algae, phytoplankton and other marine plants, may be linked to higher rates of infection by pathogens native to the marine environment. Runoff from agriculture and golf courses is a major cause of eutrophication. Blooms of plankton and algae can promote growth of associated populations of marine pathogens by increasing nutrients in the water and providing microenvironments that favor growth. The prevalence of Vibrio species has been proposed as an indicator for measuring eutrophication.
Elevated seawater temperature is associated with increased incidence of shellfish poisoning and cholera. Remote sensing of sea surface temperature is being explored, but its predictive value needs further study.

References

Miller MR, Motaleb M (2007). "Scuba divers rinse tanks harbor many microorganisms." Microbe 2(12): 577.

Olsson DJ, Grant WD, et al. (2008). "Conjunctivitis outbreak among divers." Undersea Hyperb Med 35(3): 169-74.

Thompson JR, Marcelino LA, Polz MF (2005). "Diversity, sources and detection of human bacterial pathogens in the marine environment" from Oceans and Health: Pathogens in the Marine Environment, Belkin S and Colwell RR (eds.).

Washburn BK, Levin AE, et al. "Identification of bacteria in scuba divers' rinse tanks." Undersea Hyperb Med 37(4): 233-40.

Want to learn more?

Do I sit or stand?

Tue, 04 Sep 2018 20:19:11 GMT

We are fairly spoiled here in South Florida with dive boats set up for easy diving. But as we have seen on some of our travels, sometimes we need to do water entries outside of the normal one we do.

The Easy In: Tips for Performing the Giant Stride Entry (GSE)Always evaluate the entry area before gearing up. This is especially important if diving from a boat. Check for any visible hazards. Entry areas vary from boat to boat. Some are as much as six feet above the surface of the water making it necessary to perform a high-platform version of the GSE. You may need assistance from a crewmember, especially if there are no handrails or bars to grasp for balance. A water-level swim platform extending from the stern of a boat is the easiest type of entry area. If you are diving from a stable platform such as a pool deck or dock, check the water level to confirm it is deep enough for a safe entry. If you don’t know the depth, do not enter the water to avoid an injury.

Step One — Approaching the Entry Area

If diving from a boat, you will be given a pre-dive briefing to learn boat procedures and specifics about each dive location. Following the briefing, finish donning your gear and perform a buddy check with your dive partner. Make sure your gear is in place and working properly. Also check the tank to assure the air is turned on. Depending on boat policies and crew instructions, you will either carry or wear your fins to the entry area. When carrying fins, proceed to the entry and don the fins prior to the GSE. If you are asked to wear your fins, slip them on and carefully shuffle heels first or step sideways to the entry point.

After donning the fins, place your mask securely on your face and the regulator in your mouth. Partially inflate your buoyancy compensator (BC). Move to the outer edge of the platform, place the balls of your feet on the outer edge and extend the fin blades over the water. Whether entering the water from a rocking boat platform or a stationary pool deck, position your feet so the fin tips are not below the surface as you begin your giant stride. Once you are properly positioned and ready to make your entry, take one last look into the water close to the entry point to confirm there are no obstructions (such as another diver) in the vicinity. Watch for diver’s bubbles beneath the surface. If you see any bubbles, delay your entry until the area is clear.

Step Two — Securing Your Gear

Once you have ascertained that the entry area is clear, secure your gear by placing the palm of your hand over the second-stage regulator and spread your fingers across the front of the mask. Gently but firmly hold the regulator and mask against your face to prevent them from becoming dislodged on entry. If you are wearing a conventional weight belt, use your free hand to hold the buckle in place. This will prevent the buckle from opening on entry, possibly allowing the loss of the weight belt.

When wearing a weight-integrated BC, use one hand to secure your mask. The other hand can be used to hold gauges close to your body or used to secure the mask strap. The choices you make are determined by your gear configuration and personal preference. Your scuba instructor can help you decide what works best for you.

Step Three — Giant Stride in Action

Now that you have completed Steps 1 and 2, it is time to complete the entry. After a quick look to confirm the area below is clear, place hands in their proper positions, look straight ahead and take a giant step outward from the entry platform. To execute a successful giant stride, it is especially important to look and stride toward the horizon. By doing so, your body will remain vertical, creating the desired entry into the water.

Either leg may be used to stride outward from the platform. Raise the leg high, keeping the fin tip pointing upward to avoid dragging it in the water, which can cause an awkward “face plant” entry. The foot remaining on the platform will pivot on the edge as you are carried away from the boat by the momentum of the giant stride. As you take this giant step away from the boat, enough space will be left for the scuba tank to clear the entry platform.

In rocky seas, proper timing is critical to making a safe GSE. Time the giant stride entry for when the boat pauses at the peak of the platform’s upward movement just prior to the boat’s descent. The split-second timing will prevent you from being thrown off balance by the upward motion of the boat. Instead, you and the boat will both move in a downward motion at the same time.

Step Four — Ready to Dive

When executing a giant stride correctly, you will enter the water in a vertical position. If striding from a low platform, you can minimize the entry depth by bringing your legs together immediately after contacting the water. This motion will reduce your downward momentum by creating an upward thrust. When making a GSE from a higher platform, this is not appropriate. Instead, immediately after making your giant stride, bring your legs together in a straight line with your torso and make a sleek entry. You will go a little deeper into the water but due to the partial inflation of the BC, you will surface quickly and safely.

After every entry, regardless of where, when or how high, always remember to immediately turn to the boat or shore personnel and give an OK signal by placing your fingertips on the top of your head. If you need assistance, wave your hand(s) back and forth above your head.

“Have a Seat, Please”: The Controlled Seated Entry

The controlled seated entry (CSE) is pretty much as its name implies — it’s a controlled entry done from a seated position. The CSE is typically performed from a platform no higher than 12 to 18 inches (30 to 46 cm) above the surface of the water. Platforms include small boats, swim platforms, pool decks, a dock or the gunwale of an inflatable. The CSE can typically be done in place of the giant stride or backroll entry and allows a slow, gentle entry instead of a big splash.

It is appropriate to use the seated entry when obstacles may be below the surface or when attempting to enter water with a current. Using this type of entry in a current, allows you to hold onto the platform or current line until your group is ready to descend together. By descending together, you are less likely to be separated from your group.

The seated entry is also helpful if you prefer to slip into your scuba unit after entering the water. This technique is very useful for divers with back problems or other issues because the weight of the gear is not placing strain on your back. At the end of the dive, you can remove the scuba unit before exiting the water. Just be sure that your buddy or a crewmember is available to assist with securing the scuba unit after removal.

STEP 1

The first step begins by seating yourself on the edge of the entry platform or, in our case, the pool deck. Don your fins and scuba unit. Your buddy or divemaster may need to assist you when donning the scuba unit. After the unit is in place, confirm that the gear is secured properly. Hoses and gauges need to be clipped and stowed to avoid the possibility of getting caught on the platform. Now partially inflate the buoyancy compensator (BC), don your mask and place the regulator or snorkel in your mouth. As you begin the entry, you are seated so that your bottom is near the edge of the platform, your legs are bent at the knees and your lower legs and feet are in the water.

STEP 2

For the CSE to be successful, proper placement of the hands is critical. To begin this step, place the heel of your right hand on the edge of the pool deck, fingers facing the deck and the wrist near your thigh. This hand position may feel awkward at first, but hand placement — with the heel of the hand on the edge of the platform and the fingers pointing away from the water — is important as you initiate Step 3.

For this exercise, the model shown here is entering to the right, but the CSE is performed the same way whether you pivot to the right or the left. You will maneuver your body in the direction of your hands.

STEP 3

The next three steps are broken down for the purpose of explanation but, when you perform the entry, will be executed in one continuous pivoting motion. You begin seated on the pool deck facing the water and finish floating in the water facing the deck. During the entire process, you will remain in control of the entry.

With gear in place and right hand positioned as in Photo 2, move your left arm across your torso while twisting to the right, pivoting on the right hand, transferring your weight onto your arms. The right arm will remain straight (vertical to the pool deck), allowing you to stay close to the edge of the pool.

STEP 4

This step begins as you place your left hand on the pool deck. The left arm will remain vertical to the pool deck with fingers pointing toward the deck. The hands will be shoulder-width apart. You will be leaning slightly forward, facing away from the water. At this point you have the option of stopping the entry process if needed or continuing on to Step 5.

STEP 5

The final step provides a transition from pool deck to water. Done correctly, there will be little or no splash upon entry. With both hands and arms in the position shown in Step 4, slowly lower yourself into the water. Your partially inflated BC will provide the buoyancy needed as you lower into the water. At this point you may wish to add more air to your BC to float comfortably at the surface while you wait for your buddy to enter.

After reviewing the steps for the controlled seated entry, it is easy to understand why many divers prefer this method of entering the water. The prime benefit is that you are in control at all times and feeling in control helps calm pre-dive anxiety or jitters. You also have the option of halting the entry if needed, which cannot be done once you’ve initiated the giant stride or back roll. Both of these methods can create a jarring entry if not done correctly. We suggest you take time to practice the CSE so you can move with confidence from Step 1 to Step 5. This will enable you to start your dive with a gentle, easy entry.

The Modified Controlled Seated Entry

The controlled seated entry described in this column might need to be modified for those with certain mobility issues. If you have particular physical concerns, discuss them with your instructor. Together the two of you can likely come up with a modified seated entry technique that will get you in the water safely and easily.

Enjoy and thanks Dive Training Magazine for the help.

Tom Stenger

Loosen up before your dive.

Fri, 03 Aug 2018 17:54:47 GMT

Improving Your Dive Performance and Comfort Isn’t a Massive Stretch

By Kristen Fassolas posted on SDI/TDI/ERDI Blog site

Stretching isn’t just for those who don tight leggings and own a yoga mat. Good flexibility can help improve your scuba diving experience and performance.

Do you sometimes struggle to put on your wetsuit or your BC or harness?
Do you find it hard to reach down to put on your fins?
Is it difficult to bend down with your gear on to reach for something you have dropped?
Are entries and exits into or out of the boat or water difficult?
Would you like to be able to reach your own tank valve if required?
Is just turning around to look at your buddy difficult?
Do you suffer from lower back pain?

If the answer to any of these is yes, you should work on improving your flexibility. Having a healthy range of motion can help with all of the above. This even includes lower back pain. It can also improve your daily life and help to prevent injuries. Taking the time to stretch even helps clear the mind.

Stretching is most effective when your muscles are warmed up. Before you stretch, complete your usual exercise routine. If you simply want to have a stretching session, do a light warm up first. This can consist of a few minutes of gentle jogging on the spot, some arm circles and some hip circles. This will get the blood flowing.

To ensure progress, aim to complete the following stretches every day or at least every other day. If done frequently, they will also help to avoid cramps from tight muscles and ease tension in your body.

Once in position, hold the stretch for 20 to 30 seconds. No stretch should be painful. If it is, adjust the intensity when you need to. Never pull or push through pain. Inhale and exhale deeply while holding the stretch, relaxing further with each exhale. Perform each stretch twice.

Chest and shoulder stretch

Stand in the middle of a doorway with one foot in front of the other. Bend your elbows in a 90-degree angle. Place your forearms on each side of the doorway. Shift your weight onto your front leg, leaning forward, until you feel a stretch in your chest and shoulder muscles.

Triceps stretch

Raise one arm up into the air. Then place the palm of your hand on your neck or back as low as possible. While doing so, keep your elbow pointing towards the ceiling. Use your other arm to gently pull your elbow back to increase the stretch. Repeat with the other arm.

Glute (buttock) stretch

Lie on your back and bring your knees up to your chest. Cross your right leg over your left thigh. Grasp the back of your left thigh with both hands. Pull your left leg toward your chest. Repeat with your opposite leg.

Quad (front thigh) stretch

Lie on your right side. Grab the top of your left foot and gently pull your heel towards your left buttock. Keep your knees touching. This will stretch the front of your thigh. Repeat on the other side.

Hamstring (back of thigh) stretch

Lie on your back and raise your right leg. Keep your left leg bent with your foot on the floor. Pull your right leg towards you, holding your thigh or calf and keeping the leg straight. Repeat with your opposite leg.

Calf stretch

Put your right leg forward, keeping it bent, and lean forwards slightly. Keep your left leg straight and try to lower your left heel to the ground. Repeat with your opposite leg.

Make stretching a new habit. Remember, good flexibility translates into a greater freedom of movement. It helps prevent injury and improves your performance and comfort both above and below the surface.

Nitrox Diving Safety

Tue, 10 Jul 2018 03:03:27 GMT

Divers training had a good article a few years ago on Nitrox issues and since most of us dive Nitrox, it is important to know some risks.

The article is quite long, so I cut to the key sections. Here is the link for the full version.

https://dtmag.com/25th-anniversary-vintage-articles/breathe-not-breathe-exploring-nitrox-controversy/

To Breathe or Not to Breathe: Exploring the nitrox controversy

By Alex Brylske

The issue of recreational nitrox diving has been at the forefront of the diving community for the past several months. There are no shortages of opinions about the topic but there seems to be very little objective information about the subject. This article is a milestone in that it addresses both the pros and cons of the activity in an objective and straightforward manner.

When we originally planned a nitrox article for Dive Training, we envisioned it as a two-part series, much like the trilogy published about the dive tables. However, we felt a two-part series increased the chances of confusion, and opted for a single, comprehensive report. We hope you will enjoy the results.

–Ed.

Recently an increasing number of recreational divers have begun purposely altering the air they breathe. Instead of using special gas mixtures to attain certain advantages while diving. These exotic mixtures go by such names as heliox, trimix, and nitrox. By far, the most common alternate breathing mixture is nitrox.

Some of you maybe already know about nitrox diving. Others perhaps have heard about it, but know very little. Even if you’ve never heard of nitrox diving, you certainly soon will. Industry estimates are that from 1985 to 1991, recreational divers engaged in 30,000-50,000 nitrox dives. And the numbers are growing. As altering the diver’s breathing mixture involves serious practical and legal questions, nitrox diving is becoming a hotly debated topic. In this article we’ll examine the issues involved I this new and controversial form of recreational diving. Hopefully, we can put the subject into perspective.

WHY USE EAN?

Why, you might ask, would divers want to alter the air they breathe? After all, humans have been breathing what Mother Nature has seen fit to provide us with for millions of years. Theoretically, the answer is simple. For land-based animals who breathe at normal atmospheric pressure, good ol’ regular air does the job of sustaining life quite well. But, when we venture either to altitude or underwater, there are certain disadvantages to regular air. At altitude we’re all aware that the reduced atmospheric pressure robs us of precious oxygen. This is why pilots must breathe oxygen when flying at high altitudes and why the cabins of jet aircraft are pressurized.

When we venture underwater, air continues to have certain limitations. But these limitations have less to do with the oxygen component of air than the nitrogen. It all centers around a topic we have explored extensively in past issues of Dive Training –decompression. The length of time a diver may remain at depth, or the amount of decompression he must undergo if exceeding the no-decompression limits, depends upon the amount of nitrogen absorbed. If a diver breathes air, he breathes a gas mixture containing 79 percent nitrogen. In an EAN mixture, oxygen is used to replace some of the nitrogen. So, instead of breathing a mixture containing 79 percent nitrogen, an enriched air mixture might contain only 68 percent to 64 percent nitrogen. Therefore, as the diver is breathing a gas containing less nitrogen, he absorbs less nitrogen in his body. This means both an extension of the decompression limits and –if required—reduced decompression time. Reduced decompression time is the primary—though not the only—benefit of using EAN.

THE ADVANTAGES OF USING EAN

As in most human endeavors, there is an up side and a down side to the EAN issue. Let’s examine the advantages before looking at the problems. As stated previously, the greatest advantage of using EAN is the extension of no-decompression limits for three of the most popular air dive tables, along with the limits for NOAA Nitrox I and II. As you’ll see, EAN can often more than double the no-decompression limits of the air tables.

Additionally, using EAN can shorten the required surface interval between repetitive dives. Or the diver can make a longer repetitive dive with the same surface interval as a comparable air dive. Either option is possible, again because the diver absorbs less nitrogen than on a comparable air dive.

While the extension of no-decompression time can be a real benefit, it is not—in the opinion of this writer—the primary advantage of using EAN. The real advantage of enriched air is that it can provide recreational divers with an additional safety margin when used with regular air dive tables or computers. Air tables and computers assume the diver will breath air containing 79 percent or 64 percent nitrogen. This means the diver actually absorbs far less nitrogen than the air tables or computer calculates. Thus, the diver’s actual nitrogen absorption will be far below what the tables or computer shows.

Using EAN in this way can be an ideal method of automatically building In the conservatism so many authorities advise when using tables and computers. It might also be a way of overcoming the risks from such unquantifiable factors such as age, obesity, cold, fatigue, and dehydration. In addition, susing EAN with air tables could help decrease the decompression sickness (DCS) rish among dive professionals—instructors and divemasters—who dive continually as part of their duties. Some diver resorts, who maintain EAN filling stations, have already implemented the policy of having their dive guides use EAN for an added measure of safety.

While using EAN with air decompression schedules offers great promise, it’s not a panacea for DCS. We still know far too little about the disorder to make any solid claims about the certainty of avoiding the bends.

Other advantages of EAN have been reported, but haven’t yet been fully scientifically documented. The first involves nitrogen narcosis. The theory is this: The breathing mixture contains less nitrogen than normoxic air, and nitrogen is responsible for narcosis. Thus, as the diver breathes less nitrogen, he is less susceptible to nitrogen narcosis than when breathing air at the same depth. Many EAN divers have confirmed this hypothesis, while others have seen no noticeable difference between air and EAN.

Another benefit experienced by many EAN divers is what can be called the “feel goods.” Quite often divers who use EAN report noticeable lack of post dive fatigue. In many cases, excessive post dive fatigue is attributable to what is termed “sub-clinical” DCS. The theory is that the higher percentage of oxygen in EAN reduces or eliminates these symptoms. The “feel goods” might also result from better oxygenation of the tissues by the enriched air-breathing environment.

A final benefit of EAN, oddly enough, is assumed to occur if a diver is stricken by decompression injury. Because the breathing gas contains a higher-than-normal level of oxygen, it’s theorized that tissues affected by these disorders will survive longer than if the diver was breathing air. Evidence also suggests that breathing EAN can help significantly reduce asymptomatic or silent bubbles after a dive.

THE PROBLEMS WITH BREATHING EAN

EAN is not a magical answer to the physiological problems facing divers. For instance, EAN divers are still subject to the same effects of Boyle’s law – squeezes and lung overexpansion. And while the reduced percentage of nitrogen will increase no-decompression time, EAN divers are not immune to DCS. In addition, EAN creates a few unique problems of its own.

We have known since the late 18th century that humans cannot tolerate breathing pure oxygen at high pressure with eventually falling victim to a disorder called central nervous system (CNS) oxygen poisoning. The symptoms of this disorder include: tunnel vision, ringing in the ears, nausea, facial twitching, irritability, and dizziness. But the most serious effect of CNS oxygen poisoning is the onset of epileptic-type convulsions. Normally, convulsions are not a life-threatening event—if they occur on land. A diver who convulses underwater, however, could drown. Thus, divers must avoid any circumstance where convulsions might arise. (This is why people with seizure disorder are usually disqualified as candidates for diving.)

A complicating factor is that individuals vary greatly in their susceptibility to CNS oxygen poisoning. Even the same individual can vary in his own susceptibility from day to day. Based on years of experience and tens of thousands of dives, both the U.S. Navy and NOAA long ago determined specific oxygen tolerance limits. The modern EAN diving community has followed suit and also adopted these limits. Recently, though, some authorities have recommended a reduction in these limits for recreational divers.

The current recommended oxygen tolerance limits for diving are determined by calculating the partial pressures of oxygen breathed under pressure. These tolerance limits are established in order to prevent divers from encountering CNS oxygen poisoning at depth. You’ll remember that, according to Dalton’s law, each gas within a gas mixture exerts a pressure proportionate to the surrounding pressure. This explains why as a diver descends, the partial pressure of oxygen he is breathing increases. If the diver continues his descent, oxygen toxicity, due to increasing partial pressures, will occur. The depth at which CNS oxygen poisoning occurs is directly related to the amount of oxygen in the diver’s breathing gas. The more oxygen in the mix, the shallower the depth for the oxygen tolerance limit.

When using normal air, the oxygen toxicity limit has no impact on divers who restrict their diving to 130 feet or less. This is because the partial pressure of oxygen in normal air does not reach toxic partial pressures until depths of more than 210 feet. However, EAN mixtures, because of their increased oxygen content, reach this limit at much shallower depths. The chance of CNS oxygen poisoning, therefore, becomes a very real concern even at recreational diving depths. For example, the Maximum Operating Depths (MODS) for NOAA Nitrox I and NOAA Nitrox II are 130 and 110 feet respectively. Exceeding these depths exposes divers to the same risk of oxygen poisoning as breathing air beyond 210 feet!

Oxygen tolerance is the reason for one of the most important rules when using enriched air: “The diver must closely adhere to depth limits.” As you’re aware, the maximum depth for recreational diving is 130 feet. This is because of the possibility of severe nitrogen narcosis beyond that depth.

However, it’s the onset of CNS oxygen poisoning that determines the depth limit for EAN, not the effect f nitrogen. Unlike nitrogen narcosis, CNS oxygen poisoning does not always come about gradually. While the diver might experience minor symptoms before convulsions occur, convulsions often begin with no prior symptoms!

Dr. Lee Sommers, diving safety coordinator at the University of Michigan, sums up the matter quite well. He states in an article in the recent issue of NAUI (National Association of Underwater Instructors) journal Sources, “I suggest that, unlike nitrogen narcosis, which appears to manifest itself progressively from mild to severe impairment, oxygen toxicity can be a much greater threat to the diver. The simple fact that the onset of oxygen-induced convulsions with no preceding symptoms is possible adds another unpredictable dimension to (enriched air) diving. Oxygen may prove to be far less forging than nitrogen!”

The conclusion is both harsh and simple: While a diver breathing air might get away with exceeding the recreational diving limit f 130 feet, it’s unlikely he’ll live to tell about it if he exceeds the depth limits using EAN.

IS EAN WORTH IT?

Some in the recreational diving industry vehemently opposed the proliferation of EAN diving. The reality is, however, that this is like trying to push water uphill. The question is no longer should recreational divers use nitrox; the fact is that they are using it. ANDI and IAND have, to date certified almost 300 instructors and more than 4,000 divers. Furthermore, authorities expect this number to double within the next year! These figures, of course, don’t account for those using EAN who have not been formally trained to do so. How many divers this involves is difficult to determine.

Rather than trying to resist the inevitable, it’s more useful to ask the question: Are the advantages of EAN worthwhile given the problems it presents? Frankly, this depends on the type of diving one does and how EAN is used.

For divers of less than 60 feet, there really is no particular advantage to using EAN over air—if increasing your no-decompression time is what you’re after. Although EAN will theoretically extend the no-decompression limits greatly, this has little practical effect. Unless a diver wears double tanks, he’d run out of air long before he reached the EAN no-decompression limits.

For dives below 130 feet, EAN provides no advantage to recreational divers. In fact, because of the increased partial pressure of oxygen, NOAA Nitrox I cannot be used safely below 130 feet. And NOAA Nitrox II can’t be used safely below 110 feet.

The advantage of using EAN to extend no-decompression time, as Table 1 shows, occurs on dives in the 60- to 130-foot range. EAN probably gives a significant enough advantage to consider its use in this depth range if you’re properly trained and closely adhere to EAN diving procedures. (See the “EAN Do’s and Don’ts “sidebar.)

Still, the primary benefit of using EAN is that it can probably enhance diving safety considerably when used in conjunction with air tables or computers. For this reason alone, enriched air deserves a close and thoughtful examination by all divers.

DO’s and DON’Ts of EAN DIVING

Be trained and certified for EAN diving: Never dive with enriched air if you haven’t completed a sanctioned course. The dangers of enriched air are both subtle and insidious. Also, certified EAN divers should never encourage friends who are not EAN-certified to use enriched air without proper training
Secure EAN from a reputable source, and never dive using a “home brew”: All divers must be certain of the quality of their breathing air. For EAN diving this means not only avoiding contaminates, but also verifying the mixture’s oxygen content. Ask whomever is providing your fill to give you a tour of the compressor/storage system, and ask them to explain the operating procedures and safeguards in place. Above all, never try to mix your own EAN.

Always personally analyze your gas before use: Only an analysis can confirm the actual percentage of oxygen in an EAN mixture. Never use a cylinder containing enriched air unless you analyze it first. And be sure to use at least two in-line analyzers. Multiple analyzers validate the results of one another.
Never exceed the Maximum Operating Dept (MOD) for the mixture you are using: The maximum depth for using EAN is not approximate or flexible. Remember, convulsions from CNS oxygen poisoning can come without warning. Know the Maximum Operation Depth for the mixture you’re using and don’t dive beyond that limit.
Use only dedicated oxygen clean and compatible cylinders: Use of non-dedicated cylinders results in a high risk of explosion, and could subject an unknowing diver to oxygen poisoning. Follow the proper labeling procedures.

Preperation at home is just as important as for a dive.

Sat, 02 Jun 2018 00:20:10 GMT

Hello Club Members,

June 1 has arrived and this means hurricane season. As we leave for our summer dive trips, Yah Caymans, we leave our homes vulnerable. Although the likelihood of early hurricanes are rare, one can never predict mother nature.

With this in mind we need to prepare our homes and cars before we leave for our trips. This means we need to keep in mind when the peak storm season is and be ready to come home from a trip a few days before a storm and find the stores empty. This should not be the time to prepare and you should have done it early. As we continue our travels, it is important to start stocking up on goods early and have them set before you leave for your vacations.

For me this is an important must do. Since I work for the City of Ft Lauderdale, I am typically called in early to assist the city to prepare for the storm. This means that while everyone is fighting for gas at the pumps, I am already at work keeping the peace. So I must have my preparations done very early. I always ensure that I have my stock in order early, which I have already done and am ready to return from a trip and goto work the next morning.

There are dozens of links to help you prepare and I have attached the links for Broward and Palm Beach EOC. If you get stuck on a trip have a plan in place with some friends of family to secure your home. Although be gentle on them because they are doing you a big favor.

With all the negatives out of the way , time to enjoy a great dive season. Stay away hurricane.

http://www.broward.org/emergency/Pages/Default.aspx

http://discover.pbcgov.org/publicsafety/dem/Pages/default.aspx

Tom Stenger

Remember to use your Signals

Sun, 29 Apr 2018 23:02:38 GMT

Hello Club,

Unless you invest in the fancy full face mask and U/W comms system, you are probably using hand signals? But, just like different languages, hand signals may get a bit confusing and the last thing you need is to send out mixed signals.

So lets review some of the basic signals right from the Open Water Dive Manual.

Here are some for Marine Life.

As we begin the summer dive season be sure to refresh on you signals and before every dive brief your buddy on any special signals you may use. That way when you give them some weird signal, they don't look at you like a confused minion.

Tom Stenger

Getting back to the Basics

Mon, 02 Apr 2018 23:01:51 GMT

As we prepare for our busy local and overseas dive season, it is always a good ideal to refresh our basic dive skills. The basic skill you learned in your Open Water Class are important every time you dive, even if you don't have to use them.

I can't tell you how many times my mask has flooded or my tank came loose as I bankrolled off of a friend's boat. Although considered a unusual issue, it was easily handles with little issue because of the confidence I had in my basic skills.

So what should I focus on and how can I practice. When ever I get new gear or items back from service, I love to jump into my community pool and test it out. I also use this time to practice some basic skills like mask flooding , regulator recovery, and locating my alternate air source.

What if you don't have a pool? Well, next time you are on a club dive at the end of the dive practice your skills. Just remember to brief your dive buddy first, so they know.

Here are some tips to start the season:

1. Do you ABC’s

Take your time to go through your kit, and make sure all is in order, and that you’re being extra thorough in assembling the elements.

Haste makes waste. So take your time.

2. Practice your basic water skills

Go through the basic dive skills.

Do a hover (if you struggle, start with the fin pivot), remove and replace regulator, remove and replace mask.

If you’re really ambitious, you can also remove and replace BCD and weight belt at the surface.

And if your buoyancy is top notch, take it up a level and try inverted hovers, trim, etc.

If you have the opportunity, also practice a few water entry strategies, such as giant stride.

2. Practice your basic water skills

Go through the basic dive skills.

Do a hover (if you struggle, start with the fin pivot), remove and replace regulator, remove and replace mask.

If you’re really ambitious, you can also remove and replace BCD and weight belt at the surface.

And if your buoyancy is top notch, take it up a level and try inverted hovers, trim, etc.

If you have the opportunity, also practice a few water entry strategies, such as giant stride.

3. Practice emergency skills

Next, move to the more advanced skills, and consider repeating these from time to time, in-season.

These include deploying an SMB, out-of-air scenario, and re-surfacing of an unconscious or injured diver.

If you dive with doubles, also practice your basic shut-down drills.

4. Work your communication skills

Agree with your buddy that at some point during the dive, you both need to communicate something on the dive, preferably rather complex, to the other. Make it scenario based, and make sure you have a sign to communicate that this is in fact just a scenario.

Bring two writing slates or wetnote books. You or your buddy then communicates a message to the other, who then writes down what he or she believes is communicated. Then you switch. Afterwards, you've compare notes and see how efficiently you've communicated the messages.

3. Practice emergency skills

Next, move to the more advanced skills, and consider repeating these from time to time, in-season.

These include deploying an SMB, out-of-air scenario, and re-surfacing of an unconscious or injured diver.

If you dive with doubles, also practice your basic shut-down drills.

4. Work your communication skills

Enjoy,

Tom

3. Practice emergency skills

Next, move to the more advanced skills, and consider repeating these from time to time, in-season.

These include deploying an SMB, out-of-air scenario, and re-surfacing of an unconscious or injured diver.

If you dive with doubles, also practice your basic shut-down drills.

4. Work your communication skills

2. Practice your basic water skills

Go through the basic dive skills.

Do a hover (if you struggle, start with the fin pivot), remove and replace regulator, remove and replace mask.

If you’re really ambitious, you can also remove and replace BCD and weight belt at the surface.

And if your buoyancy is top notch, take it up a level and try inverted hovers, trim, etc.

If you have the opportunity, also practice a few water entry strategies, such as giant stride.

1. Do you ABC’s

Take your time to go through your kit, and make sure all is in order, and that you’re being extra thorough in assembling the elements.

Haste makes waste. So take your time.

1. Do you ABC’s

Take your time to go through your kit, and make sure all is in order, and that you’re being extra thorough in assembling the elements.

Haste makes waste. So take your time.

&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;img class="size-full wp-image-7249" src="https://usadiveclub.org/images.divein.com/img/scuba-skills-train-pool.jpg" alt="Scuba skills include kit checks" width="800" height="533" /&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;

A diver taking time going through her kit - Credit: PhotoSky 4t com

2. Practice your basic water skills

Go through the basic dive skills.

Do a hover (if you struggle, start with the fin pivot), remove and replace regulator, remove and replace mask.

If you’re really ambitious, you can also remove and replace BCD and weight belt at the surface.

And if your buoyancy is top notch, take it up a level and try inverted hovers, trim, etc.

If you have the opportunity, also practice a few water entry strategies, such as giant stride.

&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;img class="wp-image-7252 size-full" src="https://usadiveclub.org/images.divein.com/img/scuba-skills-pool-buoyancy.jpg" alt="Buoyancy scuba skills practice" width="800" height="531" /&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;

A scuba diver practicing buoyancy in a pool - Credit: Royster

3. Practice emergency skills

Next, move to the more advanced skills, and consider repeating these from time to time, in-season.

These include deploying an SMB, out-of-air scenario, and re-surfacing of an unconscious or injured diver.

If you dive with doubles, also practice your basic shut-down drills.

4. Work your communication skills

&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;img class="size-full wp-image-7256" src="https://usadiveclub.org/images.divein.com/img/scuba-skills-underwater-com.jpg" alt="Scuba skills underwater communication " width="680" height="510" /&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;

Underwater communication using a slate - Credit: Globalreset

All of these skills are of course necessary for all scuba divers.. So a beginning of season run-through is valuable, and elements of it should be repeated during the season, preferably on easy dives at well-known sites.

The dive gear we never hope we have to use.

Mon, 05 Mar 2018 23:34:39 GMT

One of the most important piece of Safety Gear we can have is one we often don't even know how important it is to use.

Surface Marker Buoys (SMB's) are an important piece of safety gear to have on every dive. All scuba agencies now require it to be carried in classes and many dive boats require it as well.

But how much do you know about it and how much consideration did you put into buying yours? Surface Marker Buoys have been around for many decades and have been a part of every Technical Divers tool box. But, it's more then one other piece of gear to carry.

Although one never hopes to lose the person carrying the flag, in reality sometimes it happens. As you learned in your Open Water Class, the rule is to search for one minute and then surface. But, what if the line snaps on the flag and it continues to drift away with the charter boat following it?

This is where a SMB can be helpful to make you visible. Divers in the water are hard to see by boats. Since only your head is visible and waves can obscure visibility, a SMB can give you some height over the water.

When picking a SMB to carry you need to consider the brighter the better and size does sometimes matter. In rough seas or bright days, a dive flag can be hard to see and can be lost in the waves.

But deploying a SMB to supplement the flag on the surface now creates a bigger object to see and you can wave it.

Several divers deploying a few SMB's make a bigger target. How easy do you think it would be to see these several divers with their deployed SMB's?

In ending, SMB's can be used to make a dive boat captains job that much easier in rough seas and can be valuable when you lose the flag or the person holding it. I prefer a bright yellow because it sticks out but red and even pink are pretty bright too. I also prefer one that can be filled manually or by inserting a regulator to fill. This SMB can be inflated solidly and can be raised over the head without going limp. But like all other dive gear you need to look at the cost you are willing to pay, how you will attach it to keep it out of the way, and how big you are willing to carry.

Safe Diving

Thomas Stenger

Anyone interested in a CPR/ First Aid Class?

Sun, 04 Feb 2018 19:07:33 GMT

Hello Everyone,

I have had a few people ask me about putting on a CPR/ First Aid class for the club. As you may know I am a current Dive Instructor as well as CPR/ First Aid Trainer.

I wanted to get a feel for who may be interested. It was suggested that this could be done as a social event and that would be a great ideal.

I could either host it at a site down on Ft Lauderdale Beach for a minimal cost (paid to the building) at the USCG Auxiliary building followed by dinner down there on Ft Lauderdale Beach. It can also be hosted by a club member, if someone would like to host it at their home (my condo is too small)? Keep in mind that if we have a big turnout space may be tight. I teach at the USCG Auxiliary site and it can easily hold 50 people.

Although this would be a full certification class, you will not be issued a card. If you would like a card their is a fees, I have to pay to the certifying agency and if you would like to pay that I will issue you the card. The card is not necessary, but many need it to meet certain work requirements (IE: OSHA Standards, Daycare Workers, Boat Captains, Active Divemasters, ETC. )

The class would take about 4-5 hours (depending on how everyone is getting it) and would be scheduled on a Sun late Morning till the afternoon.

This is a great skill to have for your everyday life. If you are interested please email me and let me know it you want the card as well.

Thomas Stenger
safety@usadiveclub.org

Staying Warm leads to safer dives.

Mon, 29 Jan 2018 01:26:50 GMT

Diving in South Florida can be a year around sport. But water temps in January can get down to the low 70"s and in hind sight from say the waters off New Jersey that pretty warm. One still gets cold and this can lead to issues while diving.

So how do you maximize diving while keeping yourself comfortable? Having the right thermal protection for the dive environment is a big factor. Water draws heat away from the body 20 times faster then in air. Having the right wetsuit and it fitting right will make a big difference. Most people think that Florida is a year around 3mm suit state, but most experts will tell you that a 3mm wetsuit is only good to a low of 73 deg F. But if your doing multiple dives and the air temperature is cool, you body is working to stay warm in the water and out.

For those who dive a lot and may have less natural thermal insulation, a 5 mm may be the new standard suit for you cooler water diving. this will keep you comfortable down to the mid 60's.

How about hoods and gloves? Hoods help prevent heat loss from your head that is estimated to be 20 to 40 percent of the bodies heat loss. Gloves also help protect your fingers and reduces your loss of dexterity.

One must remember that the bodies main goal is to keep your core warm, so as the core gets cold it regulates blood flow to your outer extremities. So it is important to help the body out and protect those areas as well.

In between dives you need to rewarm the body to prepare it for the next dive. This may include peeling off the wetsuit, drying off and putting on a sweater. This will quickly allow your core to reheat.

Hydrate, Hydrate, Hydrate. Even in the cold, you body dehydrates and this causes your body to do more work with less resources.

For those wanting gadgets, technology is coming to help in the form of Thermal Garments. Many companies are now offering Thermal heated undergarments that work underwater, but they are still pricy. Check out www.heatedwetsuits.com for some examples.

If that's not in you budget, perhaps placing a heat pack against you chest near your core, can give the body that slight heat edge. Check out www.reusableheat.com for hot packs that are safe to dive with. Placing one in your suit for a dive may help you feel more comfortable thru the dive.

I guess when all else fails just wait till summer to dive. On the other hand that just take the fun out of being an avid diver. Maybe a semi-dry or drysuit is a must. But I'll let you make that call.

Thomas Stenger

Safety Coordinator

1/28/18

Under Sea Adventurers Dive Club Social

Trouble at the Surface

Trouble at the Surface

How to Control Seasickness

How to Control Seasickness

What Causes Seasickness?

How to Manage Motion Sickness

By Paul Auerbach, M.D.

What is visibility? Illuminating facts about an unclear situation

LIGHT PENETRATION

THE BIOLOGY OF VIZ

Delays and Misdiagnosis

Delays and Misdiagnosis

For the remainder of this article use the link below.

How common is scuba diving PTSD?

A few optional notes on quality of evidence

Scuba diving PTSD

Waiting to Exhale: Diving’s Golden Rule Explained

by Alex Brylske

End of lesson. Any questions?

Tips to Calculate Your Scuba Weight

Tips to Calculate Your Scuba Weight

You Have to Get Wet It's no one item that determines your buoyancy, but you plus all your gear together.

You can "ballpark" guess how much weight you need with experience, but you can only fine tune it by getting in the water.

Pay Attention to Your Tank Cylinder buoyancy characteristics change your buoyancy a lot. So, recheck your weight when changing to a different size and/or different material (steel vs aluminum) tank. Usually, but not always, going from aluminum to steel requires removing weight.

10 Ways To Save Your Life

10 Ways To Save Your Life

Save Your Life: Have Good Overall Fitness

Save Your Life: Dive With Others & Know When and Where to Dive

Preparation for Foreign Dive Travel: Considerations for Local and Exotic Destinations

Preparation for Foreign Dive Travel: Considerations for Local and Exotic Destinations

The Deadly Risk of Neglecting Your Air

THE DIVER

THE DIVE

THE INCIDENT

ANALYSIS

LESSONS FOR LIFE

Trouble at the Surface

Setting the Stage

The Dive and Rescue

Accusations, Analysis and Consequences

Subsequent investigation revealed that:

Lessons For Life

Chest compressions — The first-line response

Why is compression necessary?

CPR saves a life

Recognition of cardiac arrest

Chest compressions

Complications

Conclusion

References

5 Tips To Stay Safe On Your Next Dive Trip

Buoyancy Calculator—How Much You Need in Dive Weights

Scuba Q & A: Common Questions Asked By Nondivers

By Linda Lee Walden

Is it hard to learn to scuba dive?

8 Simple Ways You Can Help Improve Our Oceans’ Health

A Guide to Ocean Conservation Organizations and Efforts

The ocean is the largest ecosystem on Earth — it is the planet’s life support system and is affected by overfishing, pollution, and habitat...

Ocean Conservation: Turning the Tide

Did You See That? The Art of Observing Marine Life

Did You See That? The Art of Observing Marine Life

Take only pictures and leave bubbles!

How Current Are Your Rescue Skills?

DIVING SAFETY

How Current Are Your Rescue Skills?

Understanding Oxygen Toxicity: Part 1 – Looking Back

What to Do If You Have a Rash After Scuba Diving

What to Do If You Have a Rash After Scuba Diving

The Diver

The Dives

The Accident

Analysis

Lessons For Life

A “Handy” Way to Communicate: Using Hand Signals and Accessories to Communicate Underwater

A “Handy” Way to Communicate: Using Hand Signals and Accessories to Communicate Underwater

Does The Sport Diving Community Learn from Accidents?

Does The Sport Diving Community Learn from Accidents?

A Primer on Underwater Navigation Technology - InDepth (gue.com)

What to Do When You Overheat While Diving

You Have to Get Wet
It's no one item that determines your buoyancy, but you plus all your gear together.

Pay Attention to Your Tank
Cylinder buoyancy characteristics change your buoyancy a lot. So, recheck your weight when changing to a different size and/or different material (steel vs aluminum) tank. Usually, but not always, going from aluminum to steel requires removing weight.