This page is to add some story's on rebreather blunders and malfunctions. It is here to tell stories of mistakes that can be made by all rebreather divers. I hope it will be helpful to learn how mistakes can be avoided .
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First article is written by Howard Hall and can also be found on his web (published with permission) |
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Rebreather Blunders and Malfunctions Howard Hall
The introduction of the ElectroLung during the late 1960s seemed to herald a revolution within the sport diving industry. But after a few short years and several deaths, this revolution came to a crashing halt. The promise of silent, bubble-free diving was replaced by a consensus that rebreathers promise only death and multi-million dollar lawsuits. Despite the grim history and the prospect of certain death guaranteed by many friends and colleagues, I found the dream of silent diving almost overwhelming. Finally, in the late 1980s, opportunity presented itself. I received a contract to make a film about the Sea of Cortez. The film provided the funds and the justification for pursuing rebreather technology. So in the spring of 1989, Bob Cranston and I traveled to Philadelphia to train on a pair of Biomarine 15.5 rebreathers. The Biomarine 15.5 was a prototype rebreather designed to replace the US Navy's Mark 15. Fortunately for Bob and I, Biomarine failed to acquire the Navy contract and this failure left a couple dozen of these closed-circuit, mixed-gas rebreathers drifting aimlessly in the civilian community. Biomarine had two of these units at their Philadelphia factory and was willing to loan them to us, assuming we were willing to pay a considerable lease fee and, of course, sign a waiver that detailed the various and likely ways we would almost certainly die using the gear. A few months later, Bob and I donned our leased rebreathers and made our first open water dive in the Sea of Cortez. We were, at once, excited and terrified. We descended to just over fifteen feet and made it back alive. After surviving the making of our Sea of Cortez film (Shadows in a Desert Sea, WNET Nature), I acquired and highly modified my own Biomarine 15.5 rebreather. My underwater crew and I have been using rebreathers extensively ever since. And today as I write this, floating on the Undersea Hunter above a beautiful Fijian reef, I celebrated logging my 1,000th closed-circuit hour. That was the only event worth celebrating today, however. During today's dive my trimix computer screen went blank soon after beginning a descent to 270 feet where Bob and I planned to use two underwater IMAX® systems to film Richard Pyle collecting rare fish. Bob's camera jammed after running for only ten seconds. My camera failed to run at all. Our reward for total underwater cinematic failure was to spend three hours decompressing. Our rebreathers, however, worked great! And rebreather reliability is not something to be taken for granted. During my 1,000 hours of rebreather diving, the rather high frequency of equipment malfunction has only been exceeded by the much higher frequency of stupid diver mistakes. The editors of Oceans Illustrated believe this magazine's readers may benefit from a chronicle of these dangerous blunders, despite the humiliation such recounting may cause members of my crew and me. My hesitation at humiliating myself by admitting numerous stupid, life-threatening errors while diving closed-circuit is, however, well off-set by the pleasure I take in recounting the stupid mistakes my friends have made. Always assume your rebreather is going to malfunction at any moment. Always assuming that your rebreather is going to malfunction, is a life extending mind-set. The two rebreathers that I leased for my Sea of Cortez film were only 50% reliable. That is to say that the unit Bob used seemed to work just fine most of the time and the one I used almost never worked properly. Since I was paying the lease fees, this seemed completely unfair to me. But Bob never seemed inclined to trade units with me. During our second open water dive (the first having been the intrepid descent to fifteen feet) my rebreather showed an alarm light just after we reached the bottom in sixty feet of water. Seeing the alarm light, I suddenly felt my worst fears had come true. In a moment I was sure to die of oxygen toxicity! I stopped on the top of a rock, grabbed my open circuit bailout regulator (which at the time was attached to a 15 cf tank that hung from my BC harness) and hoped I could get the regulator clear before the inevitable convulsion. The seizure didn't come. After checking my secondary display (which shows the oxygen pressure readings on each of three oxygen sensors), I realized that death was not so imminent. Few things actually happen fast when using a rebreather. I had plenty of time to realize that my on-board computer (which controls the rebreather's gas mixtures) had failed and that I would have to add oxygen manually. In fact, I would have had ten minutes or more to sort the problem out even after the rebreather had quite working. Checking my instruments had easily averted a problem. The rebreather I used in the Sea of Cortez helped train me to regularly check my instruments. The rebreather encouraged regular instrument checks by failing to function properly on 80% of my dives. An argument can be made for owning a rebreather that almost never works right, since frequent failures encourage good instrument monitoring habits and familiarity with emergency procedures. Personally, however, I wouldn't go so far as purposely seeking out unreliable rebreather designs. However, there is inherent danger in rebreathers that work flawlessly almost all the time. Richard Pyle, an ichthyologist famous for discovering new fish species while diving his Cis-Lunar rebreather to over 400 feet, calls this the "Richard Pyle rebreather paradox." The paradox states that, while everyone desires a rebreather that is reliable, reliability begets complacency. Check your instruments The importance of frequent rebreather instrument checks cannot be over emphasized. Since Bob Cranston's rebreather worked pretty well in the Sea of Cortez, he developed less disciplined instrument checking skills than I did. A flawlessly working rebreather is almost as dangerous as a completely unreliable unit since reliability encourages instrument complacency. Bob discovered the wisdom of this during a dive in Grand Cayman. We were filming yellow-head jawfish in fifty feet of water below the boat early one morning. Bob had not had his second cup of coffee. After about fifteen minutes lying quietly on the bottom, Bob was suddenly stricken with dizziness and tunnel vision. Had he failed to act immediately, he would have been unconscious in less than six seconds. Bob's self- training saved him. In the event of dizziness, one should assume low oxygen and inject gas immediately, any gas. In fact, it is wise to inject both diluent and oxygen simultaneously since six seconds is seldom enough time to do more than one thing. If Bob's oxygen tank had not been turned on, attempting to inject oxygen would have failed to solve the problem. Bob injected gas then, for the first time that morning, he checked his primary display. The lights were out. The problem was immediately apparent; he had failed to turn on his rebreather. Bob turned on his rebreather and continued to assist me as I filmed the jawfish. Not wanting to admit to suffering from almost fatal stupidity, he didn't tell me he'd had a problem for over two years. Almost every closed-circuit diver I know has failed to turn on his rebreather or oxygen tank at least once. In the last two weeks while filming here in Fiji, both Richard Pyle and Mark Thurlow have admitted to this error. Be aware of the consequences of high oxygen partial pressures. But fear, with all your heart, the consequences of low oxygen levels Not wanting to admit such stupidity, Bob told me of his near black-out while in Grand Cayman two years after the incident, and only after he heard me relate my low-oxygen story to a group of aspiring rebreather divers. Unlike Bob, who was too dumb to turn his rig on in the morning, I had turned mine off on purpose. I was using an IMAX® camera to film kelp at an island near San Diego, California. I wanted to do a shot looking up the kelp plant as I swam the camera up to just beneath the kelp canopy. I didn't want any bubbles in the shot. So to minimize bubbles, I exhaled most of the gas out of my counterlung and turned my rebreather off so it wouldn't inject more gas (even if that gas was rather important). I figured there was plenty of oxygen left to keep me alive during that one short shot. I was wrong. And yes, I admit the idea was completely stupid. As I swam just beneath the kelp canopy and only about two feet below the surface, with the camera running, I suddenly saw stars, felt dizzy, and then was plunged into a dark visual tunnel that was narrowing at alarming speed. I checked my oxygen level. It read .06 ppO2. Not enough to support life! I barely had time to lift my head above the surface and take a breath.
Checking my instruments at the onset of hypoxia was dumb. A hypoxic diver seldom has time to do more than one thing. I should have immediately lifted my head or injected gas. Divers unfamiliar with rebreathers often fear them because they may supply too much oxygen and cause oxygen toxicity and convulsions, followed by drowning. While this is certainly possible, oxygen convulsions are not a major danger when diving rebreathers. Most divers use their rebreathers set at 1.3 or 1.4 pp02. Oxygen convulsions become possible at 1.6. However, you would have to be extremely unlucky to get a convulsion while diving a malfunctioning rebreather at 1.6 for a few minutes. In fact, most divers will get lucky and not be struck with oxygen toxicity even at levels as high as 2.0 or even 3.0. Even the most complacent dullard is likely to check his instruments before high 02 causes central nervous system toxicity. Several months ago I was descending past 200 feet in the La Jolla submarine canyon with Mark Thurlow. Suddenly I turned and he was gone. I looked up and saw Mark ascending rapidly while blowing gas out through his nose. A moment later he resumed his descent. When I asked Mark about it later, he sheepishly admitted that he had accidentally injected oxygen during his descent, rather than diluent. He noticed he had a problem when he checked his oxygen readings and found the needle pegged off the oxygen pressure scale. High oxygen levels do not necessarily result in dire consequences. Low oxygen levels, however, should be feared absolutely. Low oxygen levels can creep up on a diver quickly and are more likely to happen near or at the surface than at depth. Hypoxia is the cause of most rebreather fatalities. Once Bob Cranston began relating dumb rebreather mistakes, he seemed unable to stop. He once jumped in and began a dive with all of his electrical cables disconnected (the cables that connect the rebreather computer to the mechanics of the system). But a quick check of his instruments easily identified a problem, and he had no trouble returning to the boat while injecting gases manually. Once Bob jumped in with the cover of his rebreather unsecured and, at the same time, the cover of his CO2 scrubber unlatched. He didn't know he had a problem until the end of his dive when, as he ascended with our underwater IMAX® system, his cover popped off followed by the lid to his scrubber. Essentially, his rebreather completely disassembled underwater. Bob might not have mentioned this accident except that most of his buddies were watching him at the time, and he could think of no way to disguise his error. Never underestimate your capacity for doing something really stupid My best advise to an aspiring rebreather diver is to never underestimate your capacity for doing something really stupid. Although Bob's mistakes seem dumb (and certainly were), they are typical experiences for most rebreather divers. I admit to making an equal number of blunders. Actually, I make a few dumb mistakes on every trip. Those that know me can easily understand my predisposition for error. Smarter divers would seem less likely to screw up. Richard Pyle is a smart guy, most of the time. But, like Bob, he too has had problems with flooding his counterlung. He once jumped overboard with his breathing hoses disconnected. This mistake immediately resulted in a mouthful of water and flooded rebreather. Richard went to the surface, adjusted his full-face mask, and jumped back in assuming his full-face mask had leaked. Since his hoses were still disconnected, his rebreather flooded again. Of course, making that kind of mistake near the surface seems far less frightening than having a complete failure 300 feet below the surface. But Richard has done that too. Richard told me that he once forgot to insert the drain plug in his rebreather prior to a deep dive. When he looked under a rock at 300 feet, turning his rebreather upside down, all the gas flowed out the hole and his counterlung immediately filled with water. Richard's next breath was entirely saline. Fortunately, Richard always carries plenty of bailout gas. He switched to open-circuit, one of his buddies noticed the open orifice and reinserted the plug. Richard then completed his dive. Carry sufficient open-circuit bailout, and be prepared to use it Switching to open-circuit is the last resort when things go wrong on a rebreather. Most problems can be solved by monitoring instruments and adding gases manually. But when everything melts down you need enough open circuit gas to get you to the surface. In over just over 1,000 hours of rebreather diving, I've been forced to switch to open circuit less than a half dozen times. Twice I had oxygen o-rings blow out leaving the rig with no oxygen supply. In both cases, I had plenty of oxygen in the counterlung for ten minutes or more on the bottom before switching to open circuit and ascending. In other instances, I lost the loop. Failure of the counterlung to hold breathable gas is called "losing the loop." This has happened to me several times due to perforated breathing hoses or torn mouthpieces. It doesn't take much of a hole before the loop becomes unbreathable. While diving at Cocos Island, I developed a tear in my mouthpiece. The hole was small, but the small amount of salt water that entered the loop reacted chemically with the carbon dioxide scrubber materials. The foam rubber water-absorbers inside my counterlung melted, and the gas became very unpleasant to breath. Back on the surface, I fixed the torn mouthpiece by installing a new one. I should have secured the new mouthpiece with a mouthpiece tie. Oops! An hour into my next dive I turned my head to get Bob's attention and the mouthpiece popped off. Bob and Mark thought I looked pretty stupid with the mouthpiece sticking out of my mouth and the hoses floating high above my head. Of course, the counterlung immediately flooded. I switched to open-circuit. Pushing the envelope During our current film production, Coral Reef Adventure, my crew and I have logged more than twenty deep trimix dives, many of which were well below 300 feet. Our purpose for making these dives was to film, in the IMAX® format, Richard Pyle capturing undescribed fish species on the deep reef. On some of these dives we descended to below 300 feet with two underwater IMAX® cameras. Planning this film sequence seemed like a good idea at the time. One characteristic of closed-circuit mixed-gas rebreathers that make them seductive is their ability to support dives to over 500 feet and theoretically to over 1500 feet. Unfortunately, the normal tendency of divers like myself to lapse into casual stupidity is not so benignly tolerated on deep trimix dives. Trimix rebreather dives require multiple gas switches, computer manipulation, huge amounts of bailout gas of various mixtures, and hours of decompression. The degree of complication provides an enormous increase in the number of ways a diver can screw up. Of course, I take trimix dives very seriously. Unfortunately, that hasn't prevented me from making serious mistakes. My most serious error was forgetting to make a gas switch on a dive to below 350 feet. The result was a visit to the Fiji Recompression Facility and hours of recompression therapy. In the weeks that followed, I decided that forgetting to make the gas switch was understandable, considering the complexity of the dive and the demands on my attention when attempting to film at that depth with a 300-pound camera system. To remember the various gas switches and computer adjustments, I needed a checklist. This is the solution pilots have discovered for minimizing embarrassments such as finding oneself stuck at the end of the runway after skidding to a halt with the landing gear up. During the trimix dives that followed my bends incident, my crew and I have found the checklist invaluable. Now, if only I can remember to look at it. It now seems inevitable that rebreathers will become increasingly commonplace with sport divers around the world. Certainly there will be accidents as, through trial and error, divers develop the protocols for using these complicated machines. But for those divers who are willing to accept the risks and train themselves accordingly, rebreathers will open a new world of opportunity for underwater exploration. |
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Story #2 sent by inspiration diver: |
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Story #3 published with permission of Mr. B. Lipman http://www.barrylipman.com |
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Troubles with Rebreathers: A Cautionary Tale of Caustic Cocktails and Other Considerations Article and photographs ©2001, Barry Lipman, all rights reserved. www.barrylipman.com
I'd been diving a rebreather for about a year and a half and completed ninety-four dives on it before I'd ever experienced a problem. After diving the frigid North Atlantic off the coast of New England, the California kelp forests of Catalina Island, and the wild and unpredictable waters of the Galapagos Islands, a week of diving the warm waters of Curacao looked like it would be a walk in the park. My first experiences diving with the rebreather in warm-water lived up to all my expectations. It was pure pleasure not to deal with a dry-suit and gloves and all the weight and gear up time entailed in diving cold water. On the seventh of my eight days on Curacao, I planned a leisurely morning dive to photograph the guide rope that led divers to and from the house reef at Habitat Curacao. The rope runs from the end of the dock, across the sand, and down the wall to a depth of about one-hundred and ten feet, while the wall plunges down at least another fifty feet beyond that. After taking a few photographs looking up the wall and showing the rope, I had run up a little bit of a decompression obligation and decided it was time to head for shallower waters. I spent a few minutes in the sixty-foot range, and then spent about seven minutes in the forty foot range. I had just started up to the twenty-to-thirty-foot zone when, without any warning, my rebreather attempted to deliver a lungful of what tasted like Liquid Draino - the dreaded caustic cocktail. I swallowed a small amount of the caustic liquid, but before I ever had a conscious clue as to what was happening I found myself choking and coughing through my bailout regulator, which I fortunately had been wearing necklace style on a loop of surgical tubing such that it was always no more than a few inches away from my mouth. In the act of bailing out I dropped both my cameras and became positively buoyant, so I quickly kicked down to the nearest coral head and grabbed on so I didn't float to the surface. I dumped some air from my BC, reached up and grabbed the rebreather hose, and shut it off. I stayed there for a few moments, holding onto the coral head, assessing the situation. My throat felt as though some serious damage had been done - burning and throbbing from the effects of the caustic cocktail. I found myself hyperventilating as a result of the coughing and choking, so I deliberately forced myself to exhale completely and inhale slowly several conscious times in good open-circuit SCUBA style. I regained my composure, reassured by the simple fact that I was still breathing. Things could have been worse! I checked my computers and saw I still had a four minute obligatory decompression stop at ten feet with a ceiling of 5 feet, not much under ordinary circumstances, but given my extreme discomfort from what I assumed was serious throat damage, it seemed a very long time to me. I grabbed my cameras and finned towards shallower waters, paid off the decompression debt, and headed for the dock. After climbing out of the water, I slipped out of my gear and gargled with fresh water to alleviate the pain in my throat. I soon realized the damage was nowhere near as bad as I had thought, so I cleaned up my cameras with fresh water and headed off to a nearby restaurant for a soothing bowl of soup. Replaying the dive in my head, I realized I had tasted a little bit of saltwater in the mouthpiece a few times and I figured this was the clue that should have led me to abort the dive and avert the problem. Although this proved not entirely true, it would make good practice to abort any dive upon finding even a small amount of seawater in the breathing tubes. After lunch I took a good look at the rebreather to determine he cause of the problem. Upon inspection, I found a few inches of the gasket that seals the lid on the scrubber canister to be out of place, and I assumed this was where the water had entered the system. I cleaned out the canister and the breathing bags, charged up the canister with fresh scrubber, and reassembled the unit. Soon I was in the water again, diving with no problems. I did two dives that afternoon, both uneventful. The next morning, I did another uneventful dive. It was during my second dive of the morning and the very last dive of the trip, at a depth of about forty-five feet, that I received another caustic cocktail - this time without any warning. There was not a single taste of saltwater right up until I got a giant mouthful. This time I swallowed none of the caustic liquid, and I once again had my bailout regulator in place almost before I realized it. I quickly regained composure and finished the dive on my bailout regulator, making it back to the boat without any more problems. Upon returning home, I assembled the rebreather without the housing, submerged it in a bathtub to look for leaks, and found a small tear in the side of the expiration bag. That was the problem all along. The scrubber canister gasket misalignment was a red herring, possibly contributing to the problem, but not by any means the sole, or even the major cause. I reassembled the unit with my brand new backup breathing bags, tested it in the tub, and loaded it into the car for some cold-water New England diving. It was a typical day on the North Atlantic. We reached the dive site and moored in seas averaging about two to four feet. I geared up and leapt off the stern into water about thirty-eight degrees cold with visibility no more than three or four feet. As I descended, I checked my computers. I saw I was breathing far too rich a mix. I had filled my tanks with EAN36 and was breathing about 36% O2, well above what would be expected running it through the 60% nozzle as I do. I heard more exhaust gas than usual on every exhale. My air-time-remaining gauge showed I was consuming far more gas than normal. Something was wrong. At about seventy feet down the ascent line, with the above mentioned anomalies giving me the idea that something was wrong, I turned the dive. I had ascended to about thirty-five feet when I breathed in a mouthful of mildly caustic seawater. I immediately spat it out along with the rebreather mouthpiece and slipped my bailout into my mouth. I leaned back to see the rebreather hose floating above my head and out of reach. By leaning back a little farther, I was able to reach up and grab it no problem, pull it down, shut the valve, and continue my ascent. I handed up my camera to the boat's captain and climbed up the ladder. Upon opening up the rebreather's backpack, I saw that the expiration bag had become disconnected from the scrubber canister. This explained the excess exhaust bubbles as well as the (mildly) caustic cocktail. But why, or how, did the bag become disconnected? I decided the only possible culprit was the round grip on the plug that stopped up the hole in the inspiration bag meant for the Draeger oxygen gauge. I don't use it; I use the Aladdin system that attaches to the bottom of the inspiration hose on the outside of the backpack. I figured my breathing had allowed the plug to somehow depress the release on the exhalation bag. One might suspect I had not connected the fitting properly in the first place, but that is not likely. I always make sure I hear the "click" of the connector locking into place. If I don't hear it, I take it apart and do it again until I do. Then, to be certain it is tight, I place a finger on either side of the fitting and try to pop it open. If it resists a good push, then it passes the test. Of course, I then perform the positive and negative pressure tests. I do all of the above every time without fail. I take no shortcuts - ever. The next day I called Draeger and asked if they knew anything about this problem. I was told they suspected it had happened once a couple of years ago to someone diving in a swimming pool. I discussed eliminating the problem by rotating the fitting on the expiration bag so its release faced away from the plug. They felt this would be a good idea. I asked why they would manufacture the bag with the fittings oriented in such a way as to allow such a potentially disastrous problem. I was told that lowly paid workers assembled the parts without regard to the orientation; the final position of the fitting is random. I had already tried to loosen the fitting and found it too tight to budge. It was suggested I run it under hot water first, which I tried to no avail. I resorted to loosely clamping the outside of the bag's fitting in a vice. The eccentric shape of the fitting stopped it from rotating against the vice jaws. Having removed the overpressure relief valve, I was able to work through the hole and to use a common slip-joint pliers to turn the inside of the fitting by placing the pliers' jaws against the two small nubs on the fitting's inside collar. Without gripping anything with the pliers, I pressed down and turned against the nubs and the fitting loosened to where it was easy to undo it by hand. I rotated it to about one-hundred and eighty degrees away from its original position and tightened it up only as far as I could by hand.
Lessons Learned: Bailout Training: In bailout training, do not train the students to close the valve on the rebreather mouthpiece before switching to the bailout regulator. Teach the students to secure the bailout first and shut the rebreather valve down only after safely breathing on the bailout. It is far better to risk getting a little water into the rebreather than to delay getting a working gas supply to the diver in distress! Flood the rebreather, or flood one's lungs - you choose! In my experience, the amount of water that gets in through the mouthpiece is not a significant factor compared to the water that has already got in and made it necessary to switch to the bailout. In none of my three caustic cocktail experiences did enough water get into the breathing tubes to damage my oxygen transmitter, and that was my only real concern regarding water in the system. During training, to minimize the chances of any water getting into the rebreather, immediately after the student ditches the rebreather mouthpiece and grabs the bailout the instructor can grab the rebreather mouthpiece, shut the valve down for the student, and then release it to float up and out of reach. After the student is stabilized and breathing on the bailout regulator, the rebreather mouthpiece can then be retrieved and the valve can be manipulated as though it were being closed. This way, the student will train to secure the bailout first, then reach for and secure the malfunctioning rebreather mouthpiece. This is simply a matter of priorities. Secure one's breathing gas first, then try to save some malfunctioning equipment from possible further damage. Remember: in an emergency most of us will perform as we have practiced, so practice as though the drill were for real! Expiration bag fitting: Check the position of the release on the expiration bag to scrubber canister fitting and be sure it does not face the oxygen gauge fitting on the inspiration bag when assembled properly in the backpack. If it does, it can be rotated as described above. Connecting Fittings: When connecting the fittings, always make sure to hear the "click" of the connector locking into place. If it is not audible, take it apart and do it again until it is. Then, to be certain it is tight, place a finger on either side of the fitting and try to pop it open. If it resists a good push, then it passes the test. Of course, always perform the positive and negative pressure tests after each reassembly. Do all of the above every time without fail. Take no shortcuts, ever. Bailout Mouthpiece Position: The bailout regulator mouthpiece should be worn on a necklace made of surgical tubing such that it hangs no more than a few inches below the divers chin. This allows it to be popped into the mouth in one quick motion with no need to look for it or detach it in an emergency. If one receives a caustic cocktail at depth, the resulting coughing and choking could easily cause respiration of seawater and subsequent hyperventilation, panic, and even drowning if the bailout regulator is not put into immediate use. Reaching down, finding it, releasing it from its attachment, and bringing it up to the mouth take much more time than necessary or desirable. The necklace solves this allowing one smooth motion to grab and use it should the need arise. Abort Dive Upon Tasting Seawater: The presence of seawater in the breathing tubes should be taken as an indication that there is a leak of some kind in the system. Ascent should be started immediately and the rebreather should be checked carefully for the source of the leak. Seawater should never be found mingling with the breathing gas supply. Freshwater, however, may be found circulating in the breathing tubes. It is a normal result of the condensation of the diver's exhaled breath's moisture. One can actually drink this liquid safely while diving, and it can be quite pleasant. At the slightest hint that the water is not sweet - salt or caustic in taste - the dive should be aborted. Add Another Regulator: In addition to the Dräger mouthpiece and the bailout regulator, an additional open-circuit second stage for use by a distressed diver should be carried, possibly secured by surgical tubing to the side of the rebreather within reach of the rebreather diver and in plain sight of any other diver that may be in need. When assisting another diver, the rebreather diver needs to be able to switch to bailout without resorting to buddy-breathing off a shared reg. The rebreather diver should show this to any divers who will be diving at the same time and could possibly need to use it. |
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Note: My Draeger Atlantis rebreather has been modified. I have removed the twenty-seven cubic foot tank it comes with and added twin, manifolded, thirty cubic foot tanks with isolation valves. I run the Dräger regulator on one tank and conventional open-circuit SCUBA on the other. I usually dive with a small air bailout bottle in addition. In no way does any of this affect the internal integrity of the breathing bags. I am certain the modification has not increased the likelihood of getting a caustic cocktail or a leak of any kind. I have done more than a hundred dives using this exact configuration and I only had trouble on dives ninety-five, ninety-eight, and ninety-nine. I believe the modification of the breathing gas supply has enhanced the safety and practicality of the unit by increasing the gas supply available to both the rebreather and the bailout system. |
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This article is published with most appreciated permission of Mr. B. Lipman. I want to thank him for this permission. You can see more of his wonderful pictures and adventures on his homepage http://www.barrylipman.com |
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Story #4 Great Big Stuff Ups I Have Made Published with permission of Mr. Trevor Jackson
When I first started using my CCR, a friend of mine
handed me a ream of paper. On the front cover it read……..An
Introduction
to Rebreather Diving by Richard Pyle. It was one of the best things my
friend ever did for me, as it outlined many of the near death experiences
that Pyle had been through whilst he learnt to use his machine properly.
Despite vast amounts of diving experience, even the very finest divers can
come unstuck, most get to live through there experiences, some, regrettably,
don’t. So at the risk of copping a hiding from some members of the
fraternity, I present to you my own version of Pyles invaluable document. By
the time you’ve finished reading it, you may think I’m an idiot who should
never get in the water again, and if you’re lucky, you may learn something
that one day might mean the difference between making the surface, or not. I
am actually going to talk about only 2 stuff ups, and in no particular order
either, both incidents should have or could have resulted in me floating
face up in the water with a ghostly look on my face, but thankfully, by
virtue of luck [in one case] and good management [in the other] I’m still
here…….so here goes my reputation……… |
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Trevor Jackson wrote more : story #5 |
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Learning to Climb
Trees
There's a tree in my mothers back yard that is 1000
feet high. At least that’s how high it used to be. Now its probably only 50
feet high, it shrank considerably as I grew, but to two nine year old boys
it would seem a 1000ft. That’s how old we were when my brother and I first
climbed it. My mother was never the type of person to inhibit or quash any
of our swashbuckling activities as youngsters. Whether it be climbing a
1000ft tree or crossing the 50 mile river, she lived on the theory of ‘feed
em, love em, and leave em alone’’. There was actually a little bit of confusion just prior
to the jump. Simon and I had agreed that because my descents were in general
slower than his, that I would go first and set the pace on the way down. I
positioned myself on the Starboard side of the duckboard to jump in, but the
floats had appeared on the Port side of the boat, so Simon jumped first and
I would overtake him in the top 10 metres after a short stop on the surface
to get settled. At this stage our thoughts were fairly routine, and for a
few moments it was just a normal dive. I gathered a left hand full of shot
line and started to pull down; my right hand would work the button that
controls the gas level in my counterlung and occasionally lift my computers
into view so I could check that the PPO2 was being maintained at the
required level. Down through 30, 40, 50, 60, 70, 80 and 90 things were
fairly simple, we’d been to these branches often enough in our lead up
dives. At around 100 things start to take on a different feel, the sun goes
down and the moon comes up. Our helium rich bottom gas started to feel a
little heavy in the mouthpiece. Through 120 and 130 we were branching out
onto thinner and unscaled limbs, clouds came across the moon. The cyalumes
on the lower half of the shot line came slowly into view like stars breaking
through the cloudbank. |
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Published with permission on
http://www.therebreathersite.nl The anatomy of a serious diving accident.
Going to sea on a boat and diving down under the water is not the safest thing in the world to do. It is not as safe as say laying in bed at home under the blankets or sitting around watching TV, but in this day and age procedures are in place so that if an accident does occur, help is fairly readily at hand and advise can be sought at a moments notice. Professionally run charter operators and dive shops must have in place an effective procedure to rescue and evacuate a diver who has had an accident. Accidents take many forms, drowning, heart attack, decompression illness, even shark attacks. Emergency procedures must include contingency plans for any occurrence. The following story outlines some of those procedures as they were actually put into practice and some of the aftermath. Private boat owners would be well advised to work out their own procedures. If an accident occurs there will be absolutely no time to start flicking through phone books to get emergency numbers, or wondering what to do. Action must be automatic and decisive as minutes may count in determining the outcome. The featured accident occurred in May 2003, on the wreck of the St Paul. The victim was using a closed Circuit Rebreather, a device that enables the user to rebreather his/her own gas and maintain a set level of oxygen in that breathing gas. They have many advantages over normal open circuit dive gear in terms of decompression and gas consumption, but they can be deadly if not used in exactly the correct manner. The victim had 100’s of dives to his name and an accident was the last thing on his or anyone else’s mind that calm autumn day. Within minutes of entering the water however, a life-threatening struggle would be taking place. Myron Wintonyk is dead. I can see that he is dead, his face is blue. Foam is oozing from his nose and mouth. White foam like from a shaken up beer can. And not just a bit, a lot! His eyes are bulging and they’re open, staring at the sky. The foam seems even to be running from them too. His wetsuit is bloated, his arms are stiff. People are yelling. But its that blue color that tells me he is dead. Its not a natural color, it’s from a movie, or its kids playing with eye shadow. I’ve not seen one this bad before, only in pictures, only in nightmares. I know that Myron hasn’t breathed for nearly two minutes and I don’t know when the foam will stop, it just keeps coming, how can we get o2 into him if it doesn’t stop. Myron is dead. I point at him and I actually say it, “He’s Dead!” people hear me say it. Then I turn and stop and turn back again. People are looking at me for directions, they want to be ordered, and we have to do something. 24 hrs after that hellish scene on the duckboard of the Esperance Star, Myron Wyntonyk brought his wife and young son down to the boat to see the crew and pickup some gear. I came up the stairs from the passenger’s accommodation and there he was, large as life. There he was breathing on his own, standing up, not smiling yet, but alive. His wife looked at me with tears in her eyes and simply said, “thanks”. It was a phrase they would be repeating to lots of people, all round town. The Players: Myron Wintonyk, Divemaster, 300+ Dives, the victim Sean Inglis, rescue diver, 100 Dives, rescuer Rachel Murphy, Instructor, 500+ dives, rescuer Robert Cook, 300+ dives, rescuer Damon Blackwell, Instructor, 500+dives, first aid David Walton, Instructor, 500+dives, first aid Lars Van Der Reijden, Divemaster, 100+ dives, first aid Chris McEwan, Instructor, 300+dives, first aid Trev Jackson, Skipper, 500+dives, co-ordinator Simon Mitchell, Physician, 500+dives, phone advisor Chopper Pilot, name unknown Paramedic, name unknown Chopper Winch man, name unknown Coast Guard Radio Operator, name unknown Internet Chatroom Poster, critic, not present, name unknown Matthew McLean, 200+dives, witness
Saturday May 24th 2003 near Cape Moreton Qld. 7.50 am Divers are walking up to the jump point on the port side of the Esperance Star. In buddy pairs they call out there gas levels to the DM and jump in. Its one of the most beautiful days we have had all year, seas are glassy calm and the viz from the surface looks as though its exceeding 20 meters. The wreck of the St Paul lies on the sandy seafloor 40 meters below. Sunk in 1914, she is one of the most popular dives in the area, attracting dozens of divers each week when the weather permits. She is also considered to be in a depth that categorizes her as a dive for experienced divers only. In terms of diving this wreck Myron Wyntonyk, with over 300 dives and the holder of a dive master’s ticket for some years, would be considered an experienced diver. 8.00 am Myron has appeared on the front deck wearing his Closed Circuit Rebreather. He and the dive master are talking about the dive. The dive master asks Myron if he has completed all his pre-dive checks. Myron replies that he has. He looks happy and I enquire about his intended dive plan. He says he is doing a No- Deco dive of about 9 mins planned bottom time. From outward appearance his unit looks fine and all seems well. 8.05 am Myron enters the water and begins to descend with his buddy Sean Inglis. Sean reports later that Myron-“ seemed all out of shape with his gear and bubbles were coming out around his mask as if he was on open circuit” The two divers reach the bottom and can see the wreck just a few meters beyond the anchor. Sean has one eye on Myron the whole time as he felt uneasy about the way Myron seemed to be acting. “ Myron just wasn’t comfortable, he seemed to be falling out of his gear, I asked him if he was ok and he was negative , he wanted to go back up, yet he wanted to swim towards the wreck, there was something seriously wrong. Myron began to swim towards the wreck; I grabbed him and spun him around. He went into a fit and was suddenly unconscious.” 8.10 am Rachel Murphy was nearby trying to salvage an anchor and some rope she had found. She saw that Sean had grabbed Myron and was trying to drag him back to the anchor. Myron had spat out his mouthpiece and was taking in water, Rachel went to help. She grabbed her own Occy reg and tried to force it into Myron’s mouth- “It wouldn’t go in because his teeth were clenched”. The pair dragged Myron up the anchor chain passing other divers as they went. At around the 8-meter mark they were met by diver Robert Cook who quickly assessed the situation and grabbed Myron himself. Rachel broke away from the victim and went quickly back down to 12 meters. Robert began to swim Myron to the back of the boat whilst Sean continued to the surface to warn the lookouts that there was trouble. He then dived straight back down to 10 meters to commence some safety stops. Meanwhile on the boat, Damon Blackwell and myself are on the front deck looking at the bubbles coming up from the wreck. A lift bag had just appeared off the port side of the boat and we were wondering if there might be a diver doing a safety stop under it. I yelled out to Lars to keep an eye on the bag for later retrieval, as it seemed there were no bubbles near it and therefore no diver. There were heaps of bubbles coming up from near the anchor chain. Damon said-“too many bubbles, actually”. Seconds later Sean broke the surface and yelled something. All I remember hearing were the words “Myron” and “Oxygen”. At first we didn’t know what to think. I thought that Myron was stuck on the bottom or just needed a hand or something. I directed Damon to throw on his gear and get in to find out. Before he had a chance to get halfway along the deck we could hear the commotion at the duckboard at the rear of the vessel. 8.12 am Robert Cook had arrived at the duckboard with Myron. Damon had run down the port side of the vessel and had arrived there also. Lars and Dave were already pulling Myron out of the water and out of his gear. I arrived at the back of the boat seconds later. I look down at Myron and say out loud – “He’s dead”- people hear me say it. Then I turn and stop and turn back again. People are looking at me for directions, they want to be ordered, we have to do something. Myron’s face is covered with foam which just wont stop flowing. I know that we will have to clear his airway if we’ve got any chance of bringing him back. There are people everywhere and divers still in the water. Lars Dave and Damon are on the back deck with Robert and Myron, Christine is in the lounge behind me and I’m standing there in a momentary daze, truly believing that there is nothing we can do to save this mans life. I suddenly get dragged back into reality and someone is yelling, it’s me, but its all one sentence- “QUICK GET THAT GEAR OFF HIM GET THE O2 OUT YOU TWO DRAG HIM INTO THE LOUNGE SOMEONE GET THAT GEAR OFF HIM GET THAT SUIT OFF GET THE O2 GET HIM IN HERE GET HIM IN HERE GET HIM IN HERE”. 8.13 am. The boys drag Myron through the door into the lounge where Christine has already got the O2 ready; he’s as floppy as a rag doll. Dave starts mouth to mouth, checks for a pulse while Damon chops at the wetsuit to expose Myron’s chest. Chris by this stage has handed Dave a pocket mask and he continues EAR. With each breath Myron lungs ooze more foam, then finally he coughs. As soon as it looks like Myron can breathe on his own he is put on the Oxygen while someone else grabs the ventilator bag in case we need to force feed him the O2 at some point in the very near future. This has all happened in seconds. Myron has coughed up more white foam in chunky bits all through the lounge; the place smells like vomit and shit. At this point I’ve turned and raced through to the bridge and flicked through the channels of the marine radio to the station I know the local coast guard will hear me best on. 8.15am VHF Channel 81 Trev- “Coast Guard Redcliffe, Coast Guard Redcliffe, Coast Guard Redcliffe this is Esperance Star, Esperance Star, Esperance Star”. CG Operator- “Esperance Star this is Coast Guard Redcliffe go ahead please”. Trev-“Coast Guard Redcliffe we have a diver in trouble suspected of near drowning and of decompression illness, we require an immediate evacuation to hospital”. CG Operator-“Affirmative Esperance Star we will dispatch a vessel to your location, could you give me your exact position?” Trev-“Aaar Redcliffe Coast Guard we are going to require an airlift for this incident, this is a serious situation, I repeat I will require an airlift!” The coast guard operator soon asked me to go to VHF Channel 63 so I could speak to the Water Police directly. They soon transferred to the Ambulance Service who asked me to describe the patient’s condition, our position and the sea conditions. I had also made a phone call during this time and had Hyperbaric Physician Simon Mitchell on the speakerphone. 8.20am We organized the airlift with the Ambulance then Simon talked me through any secondary aid we might be able to give Myron. This included the ongoing maintenance of his airway, which we were told could present a problem at any stage. Messages from the doctor and Ambulance to and from the first aiders were transferred at a rapid rate, whilst there was still the ongoing issue of divers in the water. 8.40 am It would have been very easy at this point to get a bit slack in our normal dive supervisory duties, so when everyone was back I ordered several headcounts to ensure that the tension of the situation hadn’t made us overlook anything. Lars had been required to go out in the pickup dinghy to gather in a few divers that had lost contact with the boat. With everyone on board I began to winch the anchor as the faint drone of the Chopper could be heard from the west above Cape Moreton. Simon was still on the phone, the guys wanted to give Myron some water but Simon said ‘No Way!!!!!!!!!!!’ 8.55am We had established contact with the Helicopter. I knew the protocol for an airlift so we had started to steam with the breeze just on our port bow as fast as the ES could go. I sent several of the crew upstairs to secure anything that could be blown around and to try and lower any radio aerials they could. The chopper would be very close to us and the down force is incredible. We also had the added issue of seagoing traffic. It was after all a perfect day and there were dozens of trailer boats in the vicinity. I looked ahead and could see that there would be problems ahead I told the Chopper that we may have to adjust our course as we weaved through these boats but he didn’t respond, I don’t know if he heard anything. 9.05 am Myron was still with us. As Lars, Damon and Chris had secured the ship for the choppers arrival, Dave had stayed with him the whole time, assisted by Sean. He had begun to speak but it was gibberish. He was actually shouting through the 02 mask, it sounded like he was saying “get me to the border” but we decided later he must have meant either ‘toilet’ or ‘hospital’, or maybe ‘port’, I don’t know. 9.15am With the Paramedics on board the tension was slightly relieved. The Chopper was right above us thundering away as we weaved through a few small boats. It must have been an amazing sight for them. The Paras went over Myron and although he was critical it was determined we could move him onto a stretcher and try to get him into the Chopper. David and Sean picked Myron up and took him onto the back deck where he was strapped into a stainless steel stretcher .We then lowered the dinghy crane and hoisted Myron above and onto the top deck, all the while weaving through a mass of stunned onlookers. The chopper came bearing in and the first Para was snapped off the top deck with Myron strapped beside her in his stretcher. 9.55am Minutes later the second Para was giving the thumbs up and in an instant he was gone and the Chopper sped off to the west. I looked around the top deck at a stunned and silenced boat crew, then wandered down stairs and pulled the revs back. I turned the boat back towards the Cape and wandered if we should just go in to port straight away. We still didn’t know if Myron would live, if he had a major lung expansion injury or anything. I turned to Chris and asked her to make a cup of tea. It had just turned 10.00 o’clock; it had been quite a morning. 1.30pm We had just tied the boat up back at the Marina. It had taken three and a half hours to get in from the Cape. We had decided to call the trip off and head straight in. Rachel was beginning to shows signs of having a mild case of decompression illness. Sean Inglis had all but destroyed the inside of one of his ears in his rapid ascent with Myron in tow. Sean had voluntarily swum from 40 meters to the surface in less than thirty seconds, and then ducked back down to ten meters once he had done what he could. The whole boat was shell shocked, even the Captain. Myron had literally been dragged back from beyond the brink of death. Reports from the hospital were that he was resting and being treated for an Arterial Gas Embolism at the Wesley Hyperbaric Chamber, although the consulting physician was fairly confident that the treatment was purely precautionary. 2.00pm I went out onto the back deck to have a look at Myron’s gear to see if it could be determined what might have caused him to black out at depth. I knew that the workplace inspectors would want to confiscate the gear and find out for themselves, but I also knew that these devices would be new to them and the cause might not be apparent to someone not familiar with the equipment unless there was an obvious fault. It didn’t however, take long to see what the problem had been. On page three of the Buddy Inspiration Manual its states:
Attitude keeps you alive: Normally, closed circuit rebreathers are used by experienced open-circuit divers. This can bring a level of overconfidence which can lead to serious problems. You are a novice again, please accept that and build your rebreather experience gradually. Further into the manual on page 13: The Work of Breathing of the Inspiration is under 3 joules per litre at 50m. This is the limit specified for open circuit diving regulators. The counterlungs are in the best possible position for overall ease of breathing in each orientation of the diver. On page 28: It is essential to keep the breathing bags/counterlungs down on your shoulders. They are prevented from floating upwards by the Fasted buckle located on the lower edge of each counterlung. Then on page 31: Holding the counterlungs down is extremely important and care must be taken to ensure they are not allowed to float above the divers shoulders. If this happens, breathing resistance will increase dramatically…. Increased breathing resistance means increased CO2 retention. What the manual is basically saying is that inexperience will kill you and that if the counterlungs are not secured firmly down to the shoulders you could experience a CO2 build up, and we know that can kill you. But Myron’s counterlungs weren’t just loose and rising above the shoulder, they weren’t connected to the down straps of the harness AT ALL. This would cause them both to rise almost vertically above his shoulders, causing a massive pressure gradient between his lungs and the counterlungs. He would have to really suck to draw any breath. It would be like trying to breath off a 5-foot snorkel, all sucking with little result. That combined with the effort to get to the bottom at the St Paul, and the influences of partial pressure on the CO2 levels that were no doubt building up in Myron’s system. All of it adds up to a recipe for disaster, and it took only a cursory glance to notice that Myron’s harness was incorrectly fitted and that the counterlungs had not been attached to the harness. It was a mistake that could not have been detected when Myron was standing up in his gear on the front deck, as gravity held the counterlungs close in on Myron’s chest, but in the water there buoyancy lifted them up and high: it was a mistake of the first order. In open circuit terms it would be the equivalent of jumping into the water with your first stage not attached to your tank valve. Back to that quote on page three of the Inspiration manual. “Attitude keeps you alive: Normally, closed circuit rebreathers are used by experienced open-circuit divers. This can bring a level of overconfidence which can lead to serious problems. You are a novice again, please accept that and build your rebreather experience gradually” Myron had succumbed at depth to the insidious effects of CO2 build-up, the curse of the CCR diver. It had taken just minutes to render him unconscious, proceeded by a minute or so of appearing to have lost the plot completely. The reality in Myron’s mind would have been that although he knew something was wrong he didn’t know what and although he knew he had to do something his body wouldn’t do what his mind told it to do. Sean Inglis had described that Myron did not look right in his gear and he was correct, but not knowing about rebreathers himself, Sean couldn’t determine the exact nature of the problem. He knew enough however to stick close enough to be able to render immediate assistance to the surface when Myron lost consciousness. If a single act should be highlighted as the root cause of Myron’s survival it would be this. Followed in no small way by the first aid administered by Dave Walton at the surface. The outcome of Myron’s accident had been changed by a small degree of luck and some cool heads under extreme pressure. When Myron brought his family down to the boat the following day I couldn’t help hearing my own words echo through my head “He’s Dead”. Yet there he was. I also couldn’t get the sight of his blue face out of my mind. I asked Sean after they had left what would be the defining moment for him of the whole experience, what image would he keep forever, and it is fitting to complete this story by quoting him directly; “When I spun Myron around on the bottom and he was gone in the head, he spat his mouthpiece out and began to jerk about, all I could think about was the night before I had watched him saying goodbye to his wife and kid in the car park, I remember noticing that he seemed to spend ages up there with them. I had this picture of him standing there with them, yeh, that’s what I'll remember”
Myron’s report of the incident “It was the first dive of the weekend. It was a near perfect day and I was ready to play with my new rebreather. The first dive was on the St. Paul. It’s was a familiar site and I’d been here many times before. What a better way to start the weekend. But things didn’t start out that well. During an inspection of my gear just prior to the dive, I realized that my computer has a dead battery. This doesn’t cause any real concerns though. Another diver had a spare and it is the same brand as mine so I am familiar with its operation. After this quick fix, the gear checked out fine. Because of the last minute gear change, I was nearly the last diver into the water. This didn’t cause any concern as I didn’t plan a long dive and I’d only be a couple minutes later than the other divers. Unlike open circuit SCUBA, a rebreather requires you add diluent (in my case air) into the breathing loop as you descend. As I descended, I did have some difficulty breathing, so, I attributed it to not adding diluent fast enough. The problem abated somewhat by adding more air, more quickly. Once on the bottom, I realized that there was another issue. I had not switched from low set point of 0.7 PPO2 to the high set point of 1.3 PPO2. This had the effect of making PPN2 higher and I believe I was also suffering from high degree of Nitrogen Narcosis. I attempted to correct this situation, but I was having difficulty focusing on the task and was unable to locate the handsets to make the switch. At about that point, I became aware that something else was seriously wrong and that I was getting more anxious by the second. I signaled my buddy that I had a problem and had to ascend. Just then, I lost contact with the anchor chain and I was slightly positively buoyant. I swam back down to the chain and then I started to move along it towards the boat. My buddy grabbed me and started pulling me the other way I turned to him and signaled again, I have a problem and I have to go up. He continued to pull me down. At this point, I remember looking up and thinking I need to go up and my buddy is pulling me down. I’m not going to make it. I thought I’m sorry Gisela (my wife), but I’ve failed you. I fully expected that this would end very badly. That is the last thing I remember before being revived on board. I should note that the above paragraph was written from the perspective of a very disoriented person. I realize now that certain things didn’t make sense. I kept finding things that weren’t there on the way down. At the time, I thought that’s odd, where did they come from. On the surface, the answer is painfully obvious. My buddy understood exactly what was going on and was pulling me towards safety. I on the other hand was swimming farther down, thinking I was trying to get out. It seems that when I lost contact with the anchor chain I tuned myself 180 degrees before I reacquired it.
The next thing I remember was waking up in what appeared to be the lounge of the Esperance Star. I was lying on my side and I recognized the furniture and surroundings. Not knowing how I could possibly have gotten there, I believed that I was having a dream. Dave Walton was above me telling me that I’d had an accident. Bullshit I thought, “I’m having a dream and it’s a weird one at that”. I looked around some more. I recognized the people that I could see. I recognized the furniture. What the hell was I doing here? My back was hurting badly. I tried to lie flat. Dave would have nothing to do with this and kept me on my side. My throat was so dry I could hardly speak. I begged for water. I was told, “No, the doctor says you can’t have any”. Bloody hell, what kind of dream is this? Shortly afterwards, I saw a paramedic. She introduced herself and spoke briefly with me. I have no idea what she said. I remember thinking, “I don’t know this person”. Perhaps this isn’t a dream after all. Maybe this situation is serious. It was about this time that I lost control of my bowels. Let me tell you, it was a very unpleasant feeling, lying there in my own shit. I asked the paramedic to repeat her name. She did. I could hear the logistics being discussed in the background. Where should we air lift him from? Front of back deck? Back. I was carried out and placed in a basket on the lower rear deck. They wrapped me in a blanket and then, I was winched up onto the upper back deck with the boat winch. The helicopter returned and started to winch me up. The wind makes me dreadfully cold. I hit my head on the landing gear of the chopper. I was too weak to push myself away from it. They get me into the chopper. I ask the paramedic what her name was again. She tells me again. At this point, I was certain that this is not a dream and it was real life. OK I thought, I appear to be in good nick. I’m in a helicopter on my way to the hospital. I guess I’ll be OK. A few minutes into the flight, I started having difficulty breathing. My back hurt so much that it’s very painful to breathe. The problem grows rapidly worse. I would estimate I was taking 3 breaths every 2 seconds in an attempt to get air into my lungs. I am still on oxygen. I ask the paramedic what her name is, she tells me again. I ask how far to the hospital. She shows me her watch. No, how much longer? 5 minutes she tells me. I don’t know if I can hold out. I’ll try. I hear them radio ahead. I don’t remember the words, but it sounded like they didn’t expect me to be breathing when I arrived. Holy shit. This is serious. Soon after we landed, they had me in the emergency ward. I was still not in control of my bowels yet, and there was shit everywhere. They strapped on a special mask which (as I understood it) forced oxygen into your lungs. Although I could not take any larger breaths, I was not as starved for air. I was still in severe pain though. They asked me if they I wanted them to call my wife. I told them to wait a couple of minutes. I was thinking I’d catch my breath and talk to her myself. That would be better. Obviously, I still wasn’t thinking straight. They shot me up with drugs to make my breathing easier. They didn’t seem to help, but at least I wasn’t in immediate distress. Things happened rather quickly at this point. There were needles and IVs everywhere. Now, they’re talking about going to the Wesley for the recompression chamber. The next thing I know, I’m in another ambulance. I’m still on nearly 100% O2, but not the forced ventilator now. Once at the chamber, things slowed down again. Various tests to see how I was neurologically (stand with your eyes closed, what date is it, and the hardest of all, what time of day is it? How the hell would I know? I’ve had other things on my mind … Into the Hyperbaric chamber at 18 MSW I went for a couple hours on 100% O2 (2.8 PP02). I looked at the exact schedule, but can’t remember it. Something like 20 minutes on, 10 off, 20 on, 10 off, 30 on, and then “ascend” to 9 MSW. 30 on, 20 off, 90 on. Sound pretty boring doesn’t it? Well, it is during this time that I started to think that I was going to live through this thing. I began to wonder about the people who rescued me. I heard that Rachel is on her way to the chamber. I began to wonder what the hell I was thinking being down there. Simon Mitchell just happened to be in town and stopped by the chamber after hearing of my problems. After speaking with him and Trevor through the radio, the exact cause of my problems becomes clear. When I assembled my gear, I had not strapped the counter lungs down properly. This caused them to float over my head and increased breathing effort. Because of this, my body produced more CO2 and could not get rid of it. A CO2 “hit” is what I experienced.
About the time that I was released from the chamber, Rachel arrives for her treatment. I was feeling pretty good physically by then, so I spent some time talking with her. Again I realized the danger that my friends have placed themselves in to save my ass. I spent the night in the hospital under observation. Presumably for secondary drowning and salt-water aspiration and any other complications. I was released from the hospital at about 9:00 the following morning. I conferred with the hyperbaric chamber and was told that I did not require any follow-up treatments. Later that day, I returned to the Esperance Star to retrieve my gear and I confirmed that it is assembled incorrectly. I can’t believe that I made such a stupid mistake. Although I am physically unscathed, mentally, I am in not in such good shape. The following few days are very traumatic. I find myself crying often which is not like me at all. On the following Tuesday, I contacted a couple of my friends who were there. After talking to them, I realized that it’s not just me that’s struggling with the aftermath. They are having difficulty dealing with it as well. As odd as it seems to me, some were worried that they didn’t do enough. While I was thinking what else could they possibly have done. After all, I’m not only alive, but well. Everyone will need to deal with this in their own way, but it is apparent that it’s not a simple thing. It’s not just me that has to deal with this, but my family and my friends that were there too. I can only imagine the picture of me lying on the duckboard, “ There is no way to thank my saviors. There is no doubt in my mind that if they had not acted quickly and decisively, I would not be in the condition I am in today. Perhaps crippled, perhaps brain damaged to some extent, perhaps dead. The fact that I not only survived, but am at work on Monday is totally amazing. When I think about it for longer than a few seconds, I start to cry. I am so sorry to have put people in such danger. I am so sorry for causing such stress to my friends. Killing myself I can live with, but … Thankfully, their injuries were relatively minor in nature. I am fortunate to be alive, and as Trevor said, there was luck involved, but as I see it, it was the fact that I was on board with the right people. After that, there was no luck (either good or bad) involved. I did it to myself. No excuses. What have I learned from this incident? Well, the CCR is a serious piece of kit. This I knew. However, what I did not fully comprehend before was the fact that you MUST be able to concentrate and I mean concentrate on 10 things at once. If you can’t you shouldn’t be using a rebreather. I think it’s that simple. I lost concentration and damn near died, probably should have died. So there are several questions for me to answer over the next 6 weeks while I’m out of the water … will I dive again? Duh.. yes, for certain. Will I dive a CCR or OC? That one is much more difficult. I certainly want to dive CCR, but to determine that, I must determine if I can concentrate on 10 things at once for an extended period of time. I have to look at myself, nothing to do with diving. Can I do this? I’ve failed once. If I fail again, the chances of such a good outcome are slim at best. I have 6 weeks to think about it. I’ll keep you posted. If I decide I can’t, perhaps I should have taken that $55 I was offered for the thing at the chamber. I hear Inspirations don’t sell to well on eBay.
In closing, thanks to all involved. Trevor has mentioned many of them, but I know in my heart that Trevor himself had a big role too. If I had to guess, he kept everyone on task and made sure things got done (sound pretty easy). I owe my life to each and every one of these people. I downloaded my computer last night. I see that I was brought from 38M to the surface in less than 30 seconds. They could have killed themselves. That’s a selfless act. I was on board and having CPR administered to me so quickly that there was no brain damage, meaning that CPR began with 4 minutes of me going unconscious. Damn that’s fast. A few more seconds here or there and the result would have been somewhat less satisfactory.
From a rescuers viewpoint We rolled
him over and fluid poured from him ( like emptying a container ). When I
started EAR fluid would pour out of him with each time his chest contracted.
After the first set I looked for a pulse but could not feel it. At that time
I looked at Damon who was busy trying to cut away his wetsuit ( with a
kitchen knife )so that we could begin CPR. I'm sure that he thought exactly
the same as me " that this is useless he's dead". I continued EAR getting
more fluid pour out after each breath. I then checked again for a pulse and
thought I could feel one. Myron still was not breathing. Christine then
handed me a mask which I used for another maybe 6 breaths. It was at this
stage that Myron took his first breath and Lars called out to you "He's
breathing" I'm certain that you were on the phone
And the predictable critics “What a
great look for the industry, is this Recreational diving Trevor . Why do you
need to go so deep and stay so long when to a lot of people you can't do it
very well (Look at your History Trevor). How many people is that now on ES,
how many more people now have we lost to diving that will never try because
of what was reported in the news.
And from the Doctor “As the "diving physician" referred to in MHD's original post, I would just make the comment that this is yet another example of a critical emergency that was handled in an exemplary manner by the ES crew. My friendship with Trevor Jackson is no secret, but it is an honest friendship and I do not hesitate to tell him when I think he has missed the mark on any issue. Matter such as this are no exception. However, I have been the recipient of patients (previously) and advisor (on this occasion) during emergencies on ES, and in contrast to the vacillation and muddling that I often see, Trevor and his crew never seem to have any difficulty in facing up to what has to be done, and then doing it professionally. My congratulations to all involved. Without any doubt a life saved.” Simon Mitchell
A few months later I
was at a party recently. The conversation was lively and somehow we got onto
the subject of age. All the clichés were there; “I’m 53 but I still feel 17
inside”, “You’re only as young as the woman you feel”. It occurred to me
that of all the people in the room, I would be the only one who would say
that I felt older than I was. On the way home I sat in the cab staring out
as the lights went by, wondering why it was I should feel so drained, so
much in need of a yearlong sleep. Id been working a lot that much was true,
the boat had never been busier, almost constantly at sea for months, but Id
done that forever so it couldn’t just be that. Something else was there. Authors Note: 1] To my knowledge no charges or infringement notices have ever been issued over this incident 2] A 40 metre, 17 minute no-deco dive is possible using a closed circuit rebreather and careful depth/time monitoring
After nearly four months the whole accident thing was really only just beginning to settle down. It had been a sobering affair and it should serve to all of us as a reminder that we are in a world different from our own out there, outside our comfort zone where our the instincts we have evolved to keep us alive above the water may be tested to the full extent |
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The caustic cocktail,
a personal experience.
Story #7 Ron Micjan The Mobile Install Shop ron@tmishop.com http://www.tmishop.com503.632.5553
Many of us have heard the term used in rebreather diving called the “caustic cocktail”. From stories of just a bad taste in the mouth all the way to a lung full of nastiness. Until yesterday I had just experienced the bad taste in the mouth variety and then only once. Yesterday I was doing a dive with my friend Kent, off of the Nautilus Explorer, we were poking around the bottom of a wall at about 145 fsw, looking at very large urchin shells that were no longer occupied. I had about a minute of NDL left and began to move up the wall, Kent was about 20 feet away and 10 feet deeper than me. Interesting how fast things can change. With absolutely no warning, one breath of gas changed into a breath of liquid. I instantly had a mouth and throat full of sodalime dissolved in sea water. My trachea spasmed (that probably kept me from drowning) and blocked the mixture from my lungs but sent some into my stomach. Pulling the mouth piece out and closing the DSV took a couple seconds and I was holding my breath and spitting up into the water while the panic was rising in my brain. Fighting that off I knew I needed to breathe soon and took hold of my Air 2 that was plumbed to my air diluent cylinder and put that into my mouth, cleared it of water and took a tentative breath. Air is good. I looked over at Kent and waved my light at him a few times, no response, he was looking the other way. With only a 13 cf diluent cylinder, that was not full when I started this dive (mistake one) I knew that I only had a few breaths at the 135 foot depth I was at. I had neglected to bring along a larger bailout cylinder (mistake two) as I was not expecting to do any deco diving this trip. I headed for the surface, keeping my airway open and exhaling any time I was not inhaling off my very limited gas supply. At that point I wasn’t sure if I had the gas to make it to the surface, but I decided that I was going to make it, no ifs, ands or buts about it. I ascended the 135 feet in about 90 seconds, not the safest ascent rate in the world but the options were, as you might guess, limited. I hit the surface and waved to the skiff, not the usual diver OK but the two hands crossing above the head distress wave. Al wasted no time getting the skiff over to me and I climbed aboard all the while coughing, spitting and vomiting my lunch out, and gasping for breath. I washed my mouth out repeatedly with fresh water and asked for the onboard oxygen bottle, which Al handed down quickly. I cranked it up to 15lpm and started sucking it down. I was not feeling any symptoms of DCI but wanted to nip it in the bud if I could. The length of my bottom time, 17min, the fact I didn’t enter deco, 18 hours since my last dive and the relatively controlled ascent was evidence that I probably wasn’t going to get bent, hard. I wasn’t taking any chances, I used the whole cylinder. Then swapped my dil reg over to my O2 cylinder and started using that. By that time most of the divers were up, but some had not heard the recall and were still diving. I had this horrible burning sensation in my throat and mouth, swallowing was near to impossible and coughing hurt like hell. This was not fun. Still no DCI symptoms, Colby, the divemaster was coming by to check on my frequently and when Donny, the other divemaster, returned to the boat from his dive, he took over my looking after. He holds up three fingers and says, “how many?” I crossed my eyes and held up one finger back at him. His reply, “you’re back”. Donny knows my sense of humor.
A boat ride back to the Nautilus, off with the dry suit, plenty of water, some medical attention from Kim, a nurse who was a guest on the boat and a very sweet lady, (thanks Kim) and things gradually headed back to normal. My throat was still sore, everything, including water, tasted like crap, but with no signs of DCI, I figured the worst was over.
Its now the next day and my throat is still sore, my voice is mostly gone, similar to a case of laryngitis, and I am sitting out the morning dive and writing this article.
I took the unit apart last night and found that my scrubber lid was leaking. Either from not being tight enough, or something caught under the seal. The unit had passed the positive and negative pressure checks, but I'm thinking that when it hit the cold water it may have shrunk the rubber seal enough to allow water to trickle in, slowly filling up the canister until it overflowed into the inhale loop. I felt no increase in work of breathing, heard no gurgling, and tasted no difference in the loop, until I had a mouthful.
My lessons learned: Either fill the dil bottle before every dive, or carry a bailout cylinder with enough gas to ascend at a slower rate. (This is of course only for recreational, no deco, diving, I still carry 2 sling bottles on deco, deep, trimix dives).
In the end, the only thing that saved me was my training and just plain stubborn determination to not die. I thank my original drager instructor, Alan Studley, for the training that put me on this course of discovery into rebreathers and provided me the tools to stay alive when the shit hit the fan. Thanks Alan.
My advice to my fellow RB divers, previous performance is no guarantee of continued results. I told someone the day before this happened that I had never had a flood of my loop. I should have added the word, yet. My mistake was not in having a loop flood, but in not being prepared for that eventuality, yes I had some onboard dil accesable from OC, but not near enough. If I had been delayed in my ascent for any reason, I probably would not be here today to tell this story. The absolute number two thing in RB diving is HAVE A BAILOUT PLAN. Number one is of course know your PPO2. Don’t just assume you will never have a flood. I HAD BECOME COMPLACENT!!!!! Don’t let this happen to you. I was lucky, and I had a survival mindset, its what brought me back. Don’t depend on luck, have a plan that you know will work. How will you know it will work? Test it, see how long it takes you to bailout, you can do this shallow and have a buddy time you, then do the math for the same thing at depth, calc your OC bailout gas and then double that number, carry it every dive, even when you are feeling lazy. It is said that what does not kill you makes you stronger.
Thanks to Mike Lever and the crew of the Nautilus Explorer for their timely help, care and professionalism.
Ron Micjan 4 June 2004 Port Hardy, Canada |
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CO2
Breakthrough I don't know if there is any value in it but I thought I would convey my experiences too. About 6 months ago, I was on a trip when a buddy of mine noted how tight I pack my stack. I use the pat pat method and ensure that the stack is solid (i.e. the granules in the pockets of the scrim at the bottom [the bit where the spring is] do not move). I enquired how he packed his stack and discovered that it was much looser than me. I was concerned that I may over packing and agreed that I would follow his guidelines the following week on a shallow dive. It is also worth noting that he had had a few bad dives as he was feeling "funny" at depth and he felt that he was unfit as he couldn't keep up with me (he is MUCH fitter than me). The next week, I packed my stack exactly as per his guideline which incidentally is pretty much the "new" method. When I got into the water, we dropped to about 34ish meters and swam along at this depth for a while. After a few minutes, I noticed that I was out of breath and it felt like no matter how deeply I breathed, my unit could not give me enough gas. Also, I didn't feel right, not bad enough to abort the dive, just that this dive was somehow different to "normal" dives but I was having trouble working out what the different was. After a few moments "CO2 build up" jumped into my mind. I stopped and bailed out to OC (I didn't decrease the depth at this point). After about two minutes on OC, I didn't notice much difference. Next, I started to ascend and did start to feel much better. When this initially occurred, I signaled to my buddy that I didn't feel right and he kept an eye on proceedings. When I got to about 28m, I decided to try again with the loop so I switched back, ensuring my buddy was keeping an eye on me. Initially it started to get worse again but as I was still ascending my breathing continued to settle down. At around 22m, I was breathing normally and the dive progressed without further incident. In the post dive analysis, it became obvious that the stack was under packed and channelling had occurred. This diagnosis became more convincing when the unit was dismantled and the scrubber assembly was inspected. After that dive, I reverted to my original packing procedure and I have had no problems since. Additionally, the buddy that was having the original problems, now packs his stack tighter and has not experienced further problems. In addition to this, I have never experienced high WOB with my stack. In fact, I found the opposite to be true, when I packed the stack more loosely, it seemed like the WOB was enormous. The diagnosis of the problem was a process of elimination as there were no signs that the unit was assembled incorrectly. Also, there were no tell tale tracks in the stack to indicate channelling. So in the final analysis, the thing that I had changed was probably the cause of my problems (i.e. packing the stack too loosely).
Safe Diving Adam
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