EDUCATIONAL blog

<< First  < Prev   1   2   3   4   5   Next >  Last >> 
  • July 22, 2022 5:52 PM | Howard Ratsch (Administrator)

    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.

    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 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 45Tec 50, and Tec 65 courses, in which train you to make deeper, multi-stop decompression dives.


  • June 23, 2022 9:12 AM | Howard Ratsch (Administrator)

    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.

    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 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.

  • May 23, 2022 9:18 AM | Howard Ratsch (Administrator)

    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.

    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.

    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.

     


  • April 23, 2022 6:58 AM | Howard Ratsch (Administrator)

    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.

    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.

    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.


  • March 24, 2022 10:19 AM | Howard Ratsch (Administrator)

    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.

    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.

    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.

  • February 22, 2022 9:56 AM | Howard Ratsch (Administrator)

    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.

    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.

    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.”


  • January 22, 2022 1:22 PM | Howard Ratsch (Administrator)

    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.

    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.

    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.

  • December 23, 2021 9:29 AM | Howard Ratsch (Administrator)

    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.

    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.

    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)


  • November 22, 2021 8:11 AM | Howard Ratsch (Administrator)

    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.

    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 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)

  • October 22, 2021 1:12 PM | Howard Ratsch (Administrator)

    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.

    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.

    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)


<< First  < Prev   1   2   3   4   5   Next >  Last >> 

© Copyright Under Sea Adventurers Dive Club 2021

Powered by Wild Apricot Membership Software