Diver Down: A Tragedy of Errors

photo by wikipedia.org

An accident that is truly a mystery.

Diver Down: Dive Accidents, Close Calls and How You Can Avoid Them

Each Diver Down case presented on Seaduction.com is written by the author of "Lessons for Life" the #1 column at SCUBA Diving Magazine from 2001-2009.  Each case is based on a real incident that has been thoroughly investigated through official sources and the accounts of participants and witnesses. Names and some minor details have been changed to protect victims and their families.

By Michael Ange

This is an opinion piece, the views expressed are solely those of the author and are not necessarily indicative of the views of SEADUCTION.com or its principles.

As a diving journalist, I have been reporting the details of diving accidents for over a decade; nine years of that with one of the largest publications in our industry. Over the course of this period, I have had occasion to meet a lot of divers and unfortunately, discuss literally hundreds of diving accidents. The responsible handling of the information made available creates a fine line. On the one hand, it is important to report the details of accidents and how the same mistakes can be avoided by future divers. On the other, I feel compelled to have a certain amount of respect for the surviving family members and their friends.

I usually attempt a number of relatively harmless subterfuges to balance these competing interests. I always withhold names, make at best vague, generic references to locations, and generally try to avoid reporting accidents that are too recent. In spite of these best efforts, I repetitively get mail from family members or other concerned individuals who are upset about some representation of a deceased person’s diving skill or etc. Over the course of 10 years, it is an unfortunate statement that with one exception, every single individual was wrong about who the article was about. This error occurs frequently, because the same sets of circumstances repeat themselves in accident after accident. Only the names and the places vary.

One of the frustrations in my efforts to improve the safety of the sport has been the fact that most accidents are predictable and preventable. And, yet, they still occur. Those of us in the dive training world are seeing some interesting trends in diving. Our sport is on the cusp of what could very well become a major revolution or certainly an evolution in diving gear. Closed-circuit rebreather (CCR) technology is moving rapidly into the diving mainstream,  and with this movement, we are seeing a substantial increase in the number of closed-circuit fatalities. As is typical for any activity, the equipment frequently bears the brunt of the blame. Undoubtedly, sometimes this is justified. Just as undoubtedly, frequently it is not.  The reality is, more CCR divers means statistically more CCR accidents. It is unfortunate, but it is the law of averages.

In May of last year, a Norwegian diver died on a Poseidon/Cis-Lunar Rebreather. Traditionally, we would never report an accident that is less than one calendar year old. However, the official report from the Norwegian government was released several months ago and the details of this accident are one of those that make even a somewhat jaded old diver like me say: “Oh, my God, you have got to be kidding.” However, even that was not enough to convince me to report on an accident that is so recent. Even the routine maligning of the equipment that I have seen on a couple of the boards did not lead me to write about this accident - in spite of my urge to set the record straight (I dive this unit routinely). And then, three weeks ago, I was at a popular dive site where a diver was setting up a very similar piece of technology and I was forced to tell the individual that he was not diving—not on my site, not in my group—for nearly the exact same reasons that a young man in Norway lost his life.

Imagine, if you will, how this could occur: An active diver, in his early 30s, in good health, and apparently well-trained in the use of the equipment, shows up with a $7,000 closed-circuit system that is dependent upon a rechargeable battery. The diver inserts his pre-packed canister, connects and turns on scuba cylinders, and runs the unit through its automated self-diagnostics. When the self-diagnostic test reaches battery confirmation, the unit fails the test, and shuts down, just as it is designed to do. Obviously not being convinced of the validity of the test, the diver repeats the process, achieving the same result. Finally, in obvious frustration, the diver blows off all the tests and enters the water, pushing the unit into an automatic emergency mode. This mode of operation is designed as a fail-safe to allow a diver to reach the surface after some form of catastrophic failure on the unit. The Discovery Mark VI rebreather the diver was diving, according to the official reports, immediately went into warning mode. The warnings on this unit are quite difficult to ignore. An annoying audible beep commences, the handset flashes directions to switch to open circuit and bail out with a very clear and distinguishable pictogram, the red light on the heads up display illuminates and the mouthpiece begins to vibrate violently in the diver’s mouth. And finally, if you can possibly ignore all of these things, a red flashing beacon on the back of the rebreather flashes to warn all those around you that you have a problem. It was in this mode, according to the official reports, that our diver in Norway continued to dive, for 20 minutes according to the dive log. That was how long before the drained battery (it held a 20 percent charge at the beginning of the dive) forced the unit into survival mode by shutting off all the alarms and devoting the limited battery power to the maintenance of life-supporting oxygen levels. Sometime after this, the unit shut down completely. The diver was found a short while later in only 4 meters of water (13.2 feet), deceased. The open mouthpiece of the CCR was out of his mouth and the breathing loop was partially flooded as a result.

My initial response to reading about this accident was that the unit must have malfunctioned in some way. Surely, no one could have ignored all the warnings under the circumstances detailed in the accident report. However, investigators from the Norwegian government diving school in Bergen, Norway,  concluded that this is exactly what happened. Charging the battery demonstrated that it was able to hold a charge and dives made on the unit after the accident (under closely supervised conditions) were successful. These same test dives also revealed that all the sensors and alarms functioned perfectly within their design parameters and that the unit was responsive to warnings. Given the fact that the unit was used in actual diving tests without modification, it is apparent that the integrity of the breathing loop was not in any way compromised. The loop was partially flooded at the time of recovery, but investigators attributed this to the fact that the unconscious diver had lost the open mouthpiece allowing water to enter the system.

These rebreathers are equipped with a sophisticated black box and the downloaded data from both the accident and the two following test dives seem to verify the investigative team’s findings.

What more can you say. The number of logic failures in this accident chain is absolutely astounding.

So imagine my surprise when, only a few months after seeing this report, another diver begins to explain to me how the test sequence of his CCR is “too sensitive, and that “It always fails, but I dive it anyway.”; But my favorite excuse for not following the safe protocols for his CCR was “My instructor says I can ignore failures in test.”

At this point I am still a outraged and this emotion lead me onto this soap box. As many of my students know, my political correctness mostly comes from the editors who make my work more prim and proper. Well not this time. I am exercising author’s license to make the following potentially inflammatory statements.

The tests on ANY piece of dive gear are there for a purpose and with an electronic closed-circuit rebreather they are especially critical. Let me say it again: The warnings ARE CRITICAL. If you are too stupid to understand this, please go kill or injure yourself in some other sport. We do not need you as a statistic. If your instructor is stupid enough to tell you to ignore the warnings or bypass a test, well, it would be going too far to say “see if you can pound some sense into his thick and barren skull,” but you get my meaning. Enough is enough, and if an instructor actually gave this diver those directives, the industry needs to do a bit of policing. Ordinarily, I would discount a statement like this from a student, but I have now heard it from two different divers. Let’s just say you don’t have to hit me in the face with life-threatening hypoxia for me to get the message.  Hopefully, the same is true for most of our readers. Since I cannot document the information put out in the classes in question, I am not releasing the name of the instructor or the agency he trains under.

Lessons for Survival

Follow the manufacturer’s instructions for the use of any piece of life-support gear.

Be aware of warnings signals and properly respond when they present themselves.

If you have an instructor that knowingly tells you to ignore warnings on your life-support equipment—RUN. Run as fast as you can away from this individual and immediately report his grossly irresponsible conduct to the training agency that certified him so they may take corrective action.  

If you are paired with a dive buddy that knowingly ignores the use instructions or warnings on a piece of life-support equipment, see the paragraph above.  

If any of these lessons are surprising to you: Please step away from the SCUBA tank and look for the nearest golf course, or find another sport where you are less likely to be a danger to yourself and others. 

Now, as a bone to my editor, please direct all hate mail to the comments section below, or email me directly at mike@seaduction.com.

Note: Details from the official report of the Norwegian accident have been translated into English and posted at http://mkvi.poseidon.com/downloads/Accident_Report_IR-2010-05-31-1.pdf.

Drawing on his experience and training as a criminal investigator, boat captain, dive store owner and as an instructor trainer with multiple certification agencies, Mike Ange, Founder and chief visionary of Seaduction.com has been analyzing real-world diving accidents and fatalities for over a decade.  Publishing over 200 accident analysis and training articles in major print magazines around the globe, he is also the author of 6 diver training textbooks in use by major training agencies and the book Diver Down- Real-World SCUBA Accidents and How You Can Avoid Them published by McGraw Hill.  Mike has served on the training or safety advisory boards for TDI, SDI, NASE, SSI & ERDI.  He was the international training director for ERDI 99-04 and currently serves as the program manager for SSI's TXR (Technical Diving) Division.