Some Thoughts on Cave Diving Fatalities

A couple of thoughts and questions about the tragedies that occur all too often in our community.. I posted a similar thread in the spring, but I would like to discuss it a bit further.

Whenever there is a fatality among our ranks, we always hear about it immediately and there is usually a memorial type message post put up here, as well as on the other tech diving boards. Shortly after the memorial is put up, people begin to ask what happened, and then the speculation begins.

Once that happens, friends of the deceased angrily demand that out of respect for their friend, we please avoid speculation until the investigation is complete and the facts and the cause of the accident are released to the public, or at least the cave diving community.

The problem is, this almost never happens. After the memorial thread winds down and people stop talking about the accident, we generally do not hear anything else about it. Although the IUCRR sometimes publishes general information about the recovery, it is not usually sufficient data for someone to read and make an educated determination about what happened.

All of us were taught in our very first cavern / cave diving class that we learned the do's and don'ts from analyzing accidents, however there really is no formal venue for doing so.

This year has seen a terribly high number of fatal accidents in our community. While I seem to recall there being a lot more accidents in 2007, I have come across the names of four cave dives who perished in our caves this year, and the cause of death in three of those cases has yet to be made available to cave diving community:

Ron Simmons - Although we will never know "why" the accident occurred, we do know "how" it happened, he ran out of gas approximately 300' from the entrance.

Dean Barnhart - Dean passed away way back in Madison. While it is rumored that the cause of death was a medical condition, possibly a heart attack, no one has said for sure.

Liz Halbach - Liz passed away in a cave called "The Crack" (which I have never been to). We received a lot of details and information from her husband, who was with her at the time of the accident (and my heart goes out to him), but if it wasn't for him we would know next to nothing about what happened. As it is, she appeared to have suffered from an O2 hit, and well within the generally acceptable ppo2 limits, but no one knows for sure.

Jeff Thompson - Jeff recently passed away at Ginnie in a section that probably 90% of us have been to numerous times. All signs indicate that Jeff also received an O2 hit, but again, he was well within the acceptable ppo2 limits for his gas and the depth of the cave (it is in the 90' range there and I'm sure he was breathing 32%).

Without some sort of an analysis of what happened in three of the four fatalities, how will we ever know what to do to prevent them from happening to someone else? Do we need to start diving 28% instead of 32% in our 100' caves? Who knows?

For the most part, our community is made up of some highly educated individuals. We have physicians, scientists, engineers, etc... What is stopping us from somehow getting together and reviewing these accidents in the hopes of learning from them and possibly preventing them from happening again? There are numerous avenues we could take to acquire the official findings of the police investigation and the autopsies (FOIA or something similar maybe)

Whether we did it in the form of a "private" section of the forum here and then published our opinions or maybe had a closed door face-to-face meeting a couple of times a year, there needs to be a way we can learn from these accidents.

Although I am not a doctor or a scientist, I am pretty good at analyzing data and preparing reports and I would be glad to volunteer to help out with any committee that we can form for this purpose.

Any thoughts?

Rick Hartman

I have been thinking the same thing, thanks for posting this.

Rick,
The IUCRR has at its sole mission the responsibility to assist law enforcement or public safety agencies recover or rescue victims of an underwater cave incident.

The IUCRR report is designed to provide law enforcement authorities the who, what, where, when, why and how (if we know how) of the incident. IUCRR policies do not allow us to speculate but require us to prepare an objective report. These reports remain the property on law enforcement for their sole use in determining a cause of injury or death.

http://www.iucrr.org/p_whoweare.htm

It is our objectivity that gives us credibility with law enforcement officials. We serve at their discretion as their eyes and ears and make no findings nor conclusion. In the event we are asked by law enforcement to speculate, based on the findings at the scene we do so. Later, Medical Examiner inquiry becomes part of the investigation and not available for release except to the next of kin and the investigators assigned to the case.

Hope this helps and I appreciate your concern. We all need to keep accident analysis in our dive plans. /Ken

Rick, great idea. It does seem that accident analysis doesn't really occur, at least not the way it should. With the exception of Liz's incident (thanks to her husband), we really don't know much about any of these deaths. Some of us may know more than others because of the circles we're in, but even that information isn't always accurate. I'd also like to see something more formal in place. I'm also willing to volunteer and contribute my knowledge and background.

Ken,

I'm not knocking the IUCRR, you guys have your job to do and you do it well. I'm just suggesting that we put another system together to take up where the IUCRR's job ends.

This would not be for the law enforcement community; this would be for cave divers to learn from and hopefully to prevent more tragedies.

Rick

Rick,
Understood, but there are many who have a misconception of the IUCRR mission.

One thing you may want to be assured about is that informally, the IUCRR, has as its Instructors, the Training Directors of the NACD and the CDS. They see the reports and in some cses prepare them.

Hypothetically, if there is something that needs to be addressed in training they do what they need to do. To date, if a diver plans a dive with the rules of accident analysis in mind, it should be a safe dive.

The recent cases seem to point to improperly observing the Po2's, O2 clock and OTU's. Gas mixes are necessary to include with your dive plan. O2 incidents can and have happened in open water at depths as shallow as 60fsw over the course of days of diving. I personaly don't dive PO2's greater than 1.2 .

/Ken

Health issues can strike any time and its no ones business except for the family and close friends of the victim.

Correct me if I am wrong, but it seems than in 3 of the 4 full cave divers that have perished this year they all followed the TGADL rules that we all get hammered home in our cave classes.

These 3 cases seem to be medical/tox issues and unless my information is incorrect, in at least two of the cases (Halbach, Thompson) they occurred a couple days into multiple dives per day cave diving vacations. Are these divers overlooking the previous day's OTUs when they do these dives? Should we be discouraging people from going on "dive binges" where they run multiple back to back dives working at >1.0 PO2? Should, as Rick suggests, the standard "Cave Country mix" be changed to 28%? 30%?

The amount of mystery that surrounds these cases is what troubles me the most and if there are lessons to be learned they need to be presented to the cave diving public sooner rather than later. Waiting for information to trickle down from training director to training standards to instructors to the community at large is too slow. My 2 PSI.

I don't mean to step on any toes here, so please don't take this the wrong way. It seems to me that it is somewhat counterproductive for the training agencies to sit on or decide which information is released to the public and which is not. As has been previously menioned, saftey issues for cave diving have been traditionally learned through accident analysis. Shouldn't all of the information be made available to the cave diving community, so that we can draw our own conclusions as to what is important and what is not? It seems to me that if just a hand full of individuals determine the information flow based upon their own biases or perception, we run the risk of the accident analysis not being made available to the people that most can use it. Just my $.02

Regards,
Randy

Ok, so why are there only 2 of the 6 fatalities listed in thier report?

I agree that the info is lax.I think all cave related deaths should be made public with all the details that are known.I logged onto the IUCRR website when I started my training and was dissapointed in the info that was given.Over 300 deaths and they had less than a dozen to read about.

Rick and Bob,
I totally agree with you guys 100%.

It is great that we have the ICURR, but as has been mentioned, there is INTENTIONALLY no speculation and interpretation.

The problem is that we all DO speculate and make interpretations, but only speak of them quitely over beers at local restaurants after dives.

I know that I have personally spoken with my dive buddies about this and we never really seem to come to any useful conclusions.

Again, I am not knocking anyone and the IUCRR is a useful thing and a step in the right direction.

However, I also feel that as a community we can do better. Thanks for bringing this up Rick.

As an academic physician I would be glad to help be part of the solution (although admittedly I am not a specalist in dive medicine).

Along those lines, (but actually a sperate topic) I did a brief pubmed search and found very little. Does anyone know if these 3+ cases "oxygen toxicity" that occured at acceptable PaO2s are making there way into the medical literature? I didn't see any evidence of that. I think they at least deserve a case series. PM me if you have some information on this. I recently meet the Alachua county ME at a meeting. She seemed nice. I may ask her about this......

Hey Mike, I was hoping you would show up.

If you can meet with the Alachua ME and get her onboard, or at least to agree with our idea of taking a closer look at these incidents, that would be a GIANT step in the right direction.

All we really need would be the results of the autopsy (which she could possibly help with) and a copy of the detailed police report for an incident and we can probably piece together the rest of the information to come to a reasonable conclusion with regards to what happened. The police report should be public record... not sure about the autopsy.

I'll give you a call tomorrow and we can discuss it further.

Rick

Where did the ox-tox info come from in the Jeff Thompson incident. I havn't seen that?

It is pure speculation... but it's pretty much the agreed upon diagnosis made by us uninformed folks down here (at least until we learn otherwise).

Rick

I may not know all the details, but from what I've heard about Jeff's case, it didn't sound like ox tox to me.

ok... what do you think it might have been? (like I said... I have no idea other than speculation).

you see, this is the sort of speculation that gets us nowhere.

All the info that any of us may have is 3rd or 4th hand at best.

I'm saying that a group with access to all the information, or at least the best information, should do a careful analysis, compare with other similar incidents if any exist, make commentary, and widely disseminate the results.

Sometimes the simplest explanation is the best, particularly since there are no competing arguments, and it would appear to be a reasonable explanation. (Occam's razor) After all, normal O2 limits were empiracally established. Also, most nitrox classes don't emphasize enough (IMO) long duration, multi-day exposures of high PO2. Therefore we don't pay as close attention to them!!

Dale

Doing some "rubicon"ing

"Screening for oxygen intolerance in U.S. Navy divers"
http://archive.rubicon-foundation.or...123456789/3046

During a recent experimental oxygen dive series at the U.S. Navy Experimental Diving Unit, three divers were noted to be reproducibly oxygen sensitive. These three divers were then given additional OTTs to see if any evidence of central nervous system oxygen toxicity would be detected by these multiple tests. The additional OTTs did not produce any signs or symptoms of oxygen toxicity in these already proven susceptible divers. A subsequent review of the records of the Naval Safety Center yielded a total of 1347 OTTs from 1 January 1972 to 31 December 1981. A review of diving accidents reported during this period revealed that 26 episodes of oxygen toxicity were noted during OTTs for a derived failure rate of 1.9percent.

Conclusions from this paper are: Screening for oxygen intolerance is complicated by intraindividual variation in oxygen tolerance; U.S. Navy diving using 100percent oxygen during the period studied has had an acceptable safety record according to the data on record at the Naval Safety Center; the OTT as currently administered by the U.S. Navy does not identify all individuals who are relatively susceptible to oxygen toxicity; those individuals who do fail the OTT are unusually susceptible to oxygen toxicity


So it seems that personal variability in susceptibiliy is a considerable concern and that for a small percentage of divers the limits may not be adequite. Also that testing would be unlikely to identify all unusually susceptible divers.

I believe that the US Navy stopped giving O2 tolerance tests in the late 80s. It was deemed that day to day variances in indivuduals made the test inadequate.

It seems that one of the guys the test showed as susceptable toxed 6 more times out of 33 tests (18%) roughly 9 times as often as the identified average.

Poor guy.

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Originally Posted by rick68fl

ok... what do you think it might have been? (like I said... I have no idea other than speculation).

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I was told about the incident by someone who was at Ginnie that day and witnessed the topside events. Based on the information I heard, it sounds like it was medically related. In other words, what happened was going to happen whether he was diving or doing something else. I'd be interested in seeing the autopsy report. However, I'm not sure that they even looked beyond the embolism.

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Originally Posted by bullfrog

Where did the ox-tox info come from in the Jeff Thompson incident. I havn't seen that?

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Nothing official, but but all indications seem to point in that direction. I was Jeff's buddy on all but 3 dives that week. If anyone wishes to start a separate thread on this incident, I'd be more than happy to provide info from my log, which should be nearly identical to Jeff's. I haven't gotten the opportunity to view his computer log or have an actual trace analysis of unused gas, but plan to do both.

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Originally Posted by mgersch

The problem is that we all DO speculate and make interpretations, but only speak of them quitely over beers at local restaurants after dives.

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I have noticed an evolutionary change that has occured with regard to dive accident reporting. I am not saying this is good or bad, I'm just commenting.

A number of years ago, when an accident occured, there was speculation or a hypothesis that was generated rapidly, that would alert the cave diving community. This speculation/hypothesis saved some lives, ie bad air, and then sometimes was way off base, but it gave awareness to something we needed to attend to. Nowadays I notice that when an accident occurs there are immediate comments, not to speculate and wait until all the facts are in. Also, there is the PC component. At one time we used to discuss an accident to learn from it quickly to make sure the same thing isn't repeated, but often there are comments not to discuss it in respect to family and friends.

As I said, I am not condemning this, just making an observation, but basically I see that the process of assessing an accident in a rapid manner occurs; unfortunately this is done in tight circles and not publicly broadcast due to the reasons mentioned above.

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Originally Posted by jimmy herbert

Nothing official, but but all indications seem to point in that direction. I was Jeff's buddy on all but 3 dives that week. If anyone wishes to start a separate thread on this incident, I'd be more than happy to provide info from my log, which should be nearly identical to Jeff's. I haven't gotten the opportunity to view his computer log or have an actual trace analysis of unused gas, but plan to do both.

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I started a thread here. Thanks for the offer. We need more people like you who are willing to look back at things like this and get whatever good we can out of it.

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Originally Posted by rick68fl

...Any thoughts?...

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Not to discuss any incident in particular. Rick, i made some outlines for myself based on accidents in our community this year (BTW this 07 seems like a terrible year for diving accidents worldwide). I think common in all these accidents w/trained divers is when something went too far off the balance curve.

- the more you dive the more chance that accident will happen to you. so when it gets too cool maybe it is a time to quit or at least to listen to the "little voice" and feed the paranoia bug
- small caves are as dangerous as high PP0s and deep ENDs. if our goal down there is to have fun why would we risk it. complex navigation, low viz and tight places can throw you off balance of the safe air reserve in an unpredictably fast escalation (consume more gas build CO2). basically rule of thirds never work in emergency, even in a solo mode, so why do we still commonly use it as a guideline?
- as some agencies teach max PPO 1.2 sounds like a safer limit to me than 1.4 especially when catalytic effect of CO2 buildup brings unpredictably fast escalation of the O2 tox. should we rather use 30% in our "disneyland" caves instead of common pre-banked 32% , and (sigh kiss your budget g-bye) dilue it w/some He?

I didn't see any thing in the first reports about siezures. I assumed MI. was there a siezure?