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.

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.

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.

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

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.

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.”

• 1 Unnecessary tragedy
• 2 5 safety points

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

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.

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.

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.

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.

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 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)

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.

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.

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)

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.

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.

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

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.

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.

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.

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.

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.

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.

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.

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 “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)