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  • Accident Analysis... lessons learned

    Enroll in any high-risk, high-stress endeavor, and the chances are that one of the first topics your instructor will throw into his or her opening conversations with you is how many ways you can kill or hurt yourself doing what it is you just signed up for. The first steps in just about every training program in the “adventure” category of things to do – from flying a plane to shooting a gun (at targets or bad guys) or climbing rocks or heli-skiing – will walk the activity’s newcomers through potential pratfalls. It’s a kind of universal mantra: learn from the mistakes of others.


    Diving courses, well, certainly ones aimed at imparting skills for technical diving, work in a similar way. The politically-correct term used in the industry is Accident Analysis, and the framework for the AA modules I have been taught, worked with, or developed and written over the years follows closely the one first constructed and then refined for teaching cave diving. In its shortest form, an Accident Analysis module boils down to three stages: here’s some advice about what works, here are some examples of people ignoring that advice, now can we agree that they were stupid and that we will try not to follow their example.


    For the record, here are three real-life scenarios that got people killed. I share these with tech students. See what you make of them.


    Scenario one: August, 2009. Three experienced sport divers attempted a deep dive off the coast of California. The participants were a dive-store owner, his friend, and a 22 year-old shop employee and DM. Although the trio had done similar dives before, none was certified beyond sport-diving limits. The dive shop involved did run tech programs, but they were overseen by a third-party instructor. Worth noting is that this individual was NOT part of planning the dive in question and was apparently not involved at all. By the way, the dive was planned to be around 60 – 65 metres using air as back-gas. It turned out that the actual dive’s depth exceeded the plan at 70 metres plus. During ascent, the “team” lost contact with each other and the 22 year-old man was seen drifting away from his dive “buddies” and was sinking. After some time, his body was found on the surface.


    Scenario two: November 2009. Two divers attempted to dive Eagles Nest on CCRs. On a previous occasion, the pair had been taken to the “cavern” area of the nest by an instructor teaching them a course on CCR which they did not pass. For the record, one must apply a very liberal definition of Cavern to describe any part of the entrance to Eagles Nest, an extensive and very deep (80 metres plus) cave in Hernando County, Florida. Also for the record, neither man was cave certified, nor was the instructor who had previously taken them to the cave for training dives, a cave instructor. During their ill-fated final dive together, the two CCR divers had opted to use a diluent in their rebreathers was hot for the depth they attained (reportedly one containing 18 percent oxygen). If this were the case, it would have made impossible at depth controlling their setpoint (partial pressure of oxygen) at recommended levels of 1.2 or 1.3. Also, a meaningful diluent flush, cell test would have been impossible. At some point, approximately 170 metres from the cave’s entrance area, one of the divers experienced difficulty and died. His body was recovered in one of the deepest sections of the cave some time later by a team experienced in deep-water body recovery.


    Scenario three: In mid-November 2008, the bodies of two divers were recovered from Wayne’s World (aka School Sink), Pasco County, Hudson, Florida. Wayne’s World is considered an advanced cave dive yet only one of the buddies had ANY overhead training, and that was only an Intro-to-Cave card – well shy of what’s recommended to dive this site. The other diver carried only an Advanced Open Water certification. Both were wearing traditional North Florida Cave Kit with decompression gas. Recovery divers discovered both bodies within 80-90 metres of the cave entrance. Their bodies were separated by approximately 30 metres distance. One was found at a depth of approximately 14 metres with his oxygen decompression gas deployed (oxygen is considered highly toxic if breathed deeper than around 6 metres). The other was deeper in the cave, dead on the ceiling showing signs of distress. During inventory of the dead divers’ equipment, this diver was found to have his isolator closed with one cylinder empty and the other containing at least 3500 psi.


    Here are the questions I use to begin the analysis process in the classroom.
    Where did logic chain begin to break down?
    What simple guidelines seem to have been ignored in these cases, and how might ignoring them have contributed to the seriousness of the situation these people found themselves in?
    In all three cases outlined, whom do you feel should shoulder some responsibility for these deaths?

    Of course, by its nature, this exercise is speculative since the process asks us to form conclusions based on a sandwich made from a couple of slabs of conjecture and a thin layer of fact. There is also a complex moral issue with us forming a judgment about someone’s behavior – which inevitably happens – without their input during our deliberations. After all, there may be rectitude in their behavior – although on that last point, experience does tend to suggest there are no fixes for stupidity.

    However, all that aside, the exercise serves a purpose which is not to allot blame but rather to identify errors, understand how easy it is to mess up and from that deductive analysis, avoid repeating the same mistakes ourselves.


    There’s one other shortcoming. Between you and me, I dislike using the word Accident to describe many of the examples we use to point out the kind of behavior that results in diver deaths.


    What is an accident?
    One definition of an accident is “any unplanned event that resulted in injury or ill health of people, or damage or loss to property, plant, materials or the environment or a loss of business opportunity”.

    That’s OK as far as it goes. Certainly unplanned seems to be the pivotal point, but it begs some further investigation… and definition surely. Let’s take for an example scenario three above.

    It’s well known that diving in a cave without training is a poor choice. Did the two guys who died know that diving without training, experience and kit in a cave was a poor choice? Sure they did. There’s a bloody great big sign to remind them at the cave entrance. They planned to dive ignoring that fact, and I’d wager the general consensus from fellow divers would agree as inappropriate using a definition that includes the term “an unplanned event” to describe their actions.

    Given the circumstances of their dive, their behavior was risky: they took a risk and their calculations – whether conscious or not as to how likely their choice was to backfire and kill them – was incorrect. They screwed up, assuming naturally that their intention was not to kill themselves. Think about this: One guy had around half his back-gas available. All he had to do was switch regs or reach back and check his isolator. Yet signs at the site of his death indicated he drowned.

    Is deciding to take a risk and miscalculating its inevitability an accident? Is ramming into the back of a parked car at high-speed with an alcohol level above the legal limit for a driver – whatever that limit may be – an accident? Surely it’s recklessness, carelessness or criminal. What do you think?

    The Brits use the term “death by misadventure.” For the record, the definition of this phrase in Webster’s is “a death due to unintentional accident without any violation of law or criminal negligence. Thus, there is no crime.”

    Death by misadventure does have a nice ring to it: no blame, just a couple of guys out on a lark that went wrong. Is that how you see scenario two for example, or is there more to it.? Is there some level of culpability, negligence?

    A buddy of mine tells his students that cave diving is deceptively easy.


    “Anyone can swim to the back of a cave,” he says. Another buddy tells his students that “Even an open-water diver can make a dive to 60 or 70 metres.” They also add that their statements are only true until something goes wrong. In a pear-shaped world, it’s finding the way out from the back of a cave or getting back to the surface intact from 20 storeys down that presents problems.

    When things go wrong underwater, the fundamental skill becomes survival. In diver training, this is broken down into three major tasks:
    • control the natural fight or flight (or freeze) response
    • suppress panic
    • work on getting your ass back home (This latter skill requires critical decision-making, physical and mental actions involving some level of multi tasking, which some people can do, and some cannot.)

    The ability to react appropriately when things fall apart is an acquired skill even for those who have some natural abilities and the skills to survive. It takes knowledge backed up by experience and practice. How much of each is a hugely debatable point, but I believe the diving community as a whole agrees that it takes more experience and practice than one can gain during the average technical diving class… even when full knowledge of what to do and how to handle the situation has been taught.

    Well, that’s a shocker, isn’t it? We certify divers to do dives but we believe they may need more experience and practice before they can survive something going pear-shaped!

    If this were the case, our beaches would be littered with the dead and injured and clearly they are not. Most people leave a dive class – regardless of whether it is a sport diving or tech diving class – with a full understanding that what they just earned is an OK to go out into the real world and gain experience and practice, gradually. They have the knowledge to do so well within the limits of their training. And that is the key… within the limits of their training. Without training or with a disregard of what that training taught, all bets are off. They have no knowledge and are unlikely to live long enough to gain wisdom.
    So what is the bottom line, take-home message from Accident Analysis?

    I’ve always reckoned it to be the advice to take things slowly, to be cautious, and to stay within the boundaries of your comfort zone, which are the actions of a wise diver.

    But of course the real question is, what does Accident Analysis say to you?


    ____________________

    This essay was originally published at http://decodoppler.wordpress.com/

    Steve Lewis is an active technical diver and instructor-trainer who works as a training and marketing consultant in the scuba industry.
    D_B, mselenaous, aquaregia and 2 others like this.
    Comments 6 Comments
    1. VooDooGasMan's Avatar
      VooDooGasMan -
      Dop,who should shoulder these is easy for my answer, If in a class and instructor is there to teach,then the Instructor is responsible. if a newer diver is there to gain experience from a experienced diver, you would think the experienced, but no not at all. Why? well the dive industry was made to teach this and along with that someone is held responsible. Two divers or more diving together is all on there own. Now when, Lets use padi, you get padi certified always dive with a buddy, that is a set up from the cert agency.

      It is clear when I am in the body of water with other divers I am solo, we are not buddy divers and never will be. we might enter the same time, we might see each other and that's it.

      If you enter a cave, you know the outcome, either you make it back to the entrance or you do not, if being taught by instructor then its his responsibility to get you back to the entrance.

      To me its cut and dry, either paying to be taught, or self learning.
    1. TSandM's Avatar
      TSandM -
      Some time ago, a friend of mine started a thread on whether there was any point at all in posting accident and incident reports, as they tend to fall into two classes. Either not enough is known about the accident to make any recommendations or changes in existing practice, or the departures from current good practice are so egregious as to cause most folks to shake their heads and say, "Well, I would never do that, anyway."

      As an ER doc, I know that what people think is a good idea often makes me shake my head, and I think diving is no exception. I do not know what you can do to instill prudence or common sense into human beings (and at the risk of being deemed sexist, into young adult males). If you figure it out, Steve, will you let me know? It would save a lot of medical costs . . .
    1. Dive Bug Bit Me's Avatar
      Dive Bug Bit Me -
      Doppler, firstly thank you for a very poignant post. Your question of who should shoulder the responsibility is more far reaching than meets the eye. I would suggest that the industry as a whole is at fault. Technical diving is to recreational diving what sky diving is to bungy jumping. They are fundamentally different sports. No amount of bungy jumping will train me for sky diving as sky diving requires a different set of skills to safely return to the surface of the earth. A highly skilled and well trained recreational diver doesn't have the skills or knowledge that are required to improve his chance of safely returning to the surface of the earth from a technical environment.

      In many ways, the industry positions itself as one of graduating through the ranks. You do a few OW dives and are told that you can go deeper as you gain more experience and comfort. A suggested (but not hard) limit is 60 ft (I think). Eventually you spend some money and someone accompanies you to 90 ft. Now you sport an AOW (often with terrible skills). You dive on and off for a few vacations and you've been to 90ft, so maybe a little deeper won't hurt, so 100, 110, 120 . . . 150 ft all feel good now. Suddenly we are out of the realm where our training is adequate and we don't know it (it feels safe and I have loads of experience so 130ft doesn't apply to me, besides just follow your computer's instructions you will be fine). We are now an accident waiting for our luck to run out.

      The rub is that many highly skilled recreational instructors don't necessarily realize why the limits are in place. Certainly this is not being reinforced in training being given at recreational levels. Here are some of the hair raising comments I have personally heard from recreational instructors who are still actively training students, "cave diving really isn't that difficult, you just follow the string", "don't worry, I've been to 60m plenty of times I will look after you", "why are you carrying penetration line? we are only going a little ways into the wreck?","the dive tables are established from empirical experience, don't worry if you exceed the limits nothing bad will happen its just that they haven't been tested that far out yet".

      Instead of positioning deep & overhead diving as something you can graduate into with experience (e.g. you need 100 dives for this course) should we not just position it as what it is. A completely different sport. Tech diving (deep or overhead) is not particularly difficult and with a little practice, most divers could get to the standards required for beginner tech classes. Instead many divers seem to think that experience of 20 dives to 130 ft will prepare you for a dive to 160ft in the same way as experience at 90ft does prepare you for dives to 120ft.

      Basically the limits of recreational training (and reasons for this) should be more ingrained at the recreational level with an explanation that a different sport "tech diving" exists as an alternative for those who have different requirements from diving. It should be explained to students why one sport is not necessarily better than the other, they are just different. Similarly it should be explained why you cannot take the skills taught in one sport and apply them to the other. Most importantly each instructor you train with should instill a healthy respect for the limits of your training.
    1. sharksdelight's Avatar
      sharksdelight -
      As a former BSAC advanced instructor and dive shop owner, I do not fully blame the divers for their lack of common sense and over confident feelings of invulnerability. I easily blame both dive shop owners and the dive agencies, especially the agencies. The dive agencies are in it only for the money by their extensive exploiting of so many ridiculous certifications. I did not think I was fairly advanced until I had about 600 dives on me in all kinds of conditions, good and bad. These days you see divemasters and instructors with less than 100 dives on them. Sorry, but they haven't been diving long enough or had that many varied experiences in the water to rank for what those ratings should stand for. They are good with the pool, book learning and written test preparation to pass, but do not have real world experience. When I was a skydiving jump master we used to call jumpers with 100 jumps, 100 jump wonders. These were the jumpers who had reached that plateau of skydiving but who then thought they knew it all. The same with scuba. I have always hated the 'Advanced' certification as it tells the diver that they are, indeed, advanced divers which they clearly are not with only 25 dives on their belt. I don't know if BSAC is the same as it was but then a BSAC Advanced certification diver had several hundred dives, not 25. Now PADI, NAUI and the other certifications provide the 'Get Your Left Fin Wet' certification followed by the 'Get Your Right Fin Wet' certification and they are all absurd. Go down with a GoPro cam and get your Videographer certification. Who are they kidding? The dive agencies like to promote themselves as guardians of the seas, as outreaching to people to enjoy and learn about our marine environment but that is just a baseless front.
      I would go crazy at the shop when a new diver would come in and say they were Advanced divers...with 30 dives....done over a period of 15 years. Again, who are they kidding? I hold the agencies to blame for this blatant exploitation of so called certifications, the dive shops for hiring for cheap, DMs and Instructors with minimal skills and experience, who want to use their enthusiasm in their new sport to move, unrestrained, up the certification ladder. The dive shops want to make money in a very tight business, I understand that, but they and the agencies have a responsibility to their students but look the other way, kidding themselves that things will be safe. This attitude is then passed on to the student diver.
      While I might not have the gills I had as a young diver, nothing can ever take away the experiences, both good and bad, that trained me to be a better diver. I used to tell my dive students once they got certified that now they had a learners permit and should go out and really learn to dive. The certification itself doesn't make you a diver.
    1. billgraham's Avatar
      billgraham -
      I think Steve's point is that the "unplanned" aspect of the definition of "accident" is illustrated by the fact that not one of the divers had even a "learner's permit" certification for the dives they were doing. Great article once again.
    1. raftingtigger's Avatar
      raftingtigger -
      Great article! Yes, there is a lot to be learned from accident analysis. Just look at aviation. It has been through years of accident and mishap analysis that aviation has gone from highly risky to safer than automobile travel. People still do stupid things in airplanes. Most don't plan on having an accident... But analysis and even educated speculation highlight risks that aren't obvious to many participants. Without risk awareness the participant has no idea what risks they are taking, therefore can't even plan for them.

      I would love to see (but doubt I will - the agencies are concerned about frightening away customers) accident and mishap analysis in OW training. There was a little in my DM training , but no real emphasis on the subject.

      The comment that Rec diving and Tec diving are really different sports hits home. Completely different 'bailout' options and vastly different minimum equipment needs. This is also a point that needs to get emphasized at the OW level. Yes, some instructors tell their graduates they have a 'learner's permit' and most agencies have the caveat to "dive within your limits and training", but generally these are empty words - with little information to "make it real" to the new diver.
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