Statistics: main cause of death with rebreathers

Skipbreather · 22nd September 2007, 15:57

It took 4 pages but someone finally mentioned what I see as the root cause of most accidents:

Loss of situational awareness.

If a diver is on top of whatever aspects of the dive he can control, he will be ready for most non routine occurrences (malfunctions, oversights, whatever). It is vital to be AHEAD of what is going on, not just reacting to whatever situations develop.

The loss can arise via many avenues. When new to CCR, folks won’t have the experience base to keep the big picture in mind- the basics monopolize most of their efforts. At the other end of the scale, complacency is a silky pillow that lures a highly experienced CCR diver to let his brain take a nap just when it’s needed most.

Most dangerous time of all, IMVHO, is the intermediate stage CCR diver who has built a decent experience base but has not been at it long enough to have been challenged by critical stuff breaking at the worst possible time. His kit has served him well and all those dire things that his instructor drilled him on a year or two ago are becoming just dusty scary stories that only happen to “other” divers. He looses his situational awareness- he quits ‘what if-ing’- and when an unanticipated event starts developing he blows it off or, worse, does not even notice it and what was a minor ‘situation’ quickly becomes a full blown emergency (How did that drill go?).

All mechanical things will break eventually. Dive site conditions are constantly changing. Humans forget stuff occasionally and are themselves breakable. The diver who works hard at staying in touch with all that is going on around him and anticipates- in short, has good situational awareness- has the best chance of not becoming a statistic.

I'll climb off my soap box now......

teddy2005 · 23rd September 2007, 08:56

Quote: (Originally Posted by caveseeker7)

Don't know what EDO-04 accident you refer to, but in at least one of them the one way valves to the smaller bellows were defect and not working. On both units of the dual Rebreather setup. That the diver wasn't properly trained and diving shallow water probably didn't help much, either, but those components of his RBs were not in working order. The state police of the area posted an anlysis and warning including pictures on their website, the damaged/faulty valves were clearly visible.

The state police made this report based on a biaised analysis of the machine and before enquiries were conducted in depth. The valves were not involved in the accident. I was closely involved so I think I better know thant the first alarming threads which were dispatched...

AD_ward9 · 23rd September 2007, 19:42

Quote: (Originally Posted by SteveJ)

In deaths from 1997-2004, approximately 50% were diving solo. That's not a cause but it is a strong association.

Probably 1% of sports diving is solo, by observation: I do not have any better data source on this. This means that if the 50% of deaths from solo diving is accurate, that is a very strong association.

I for one have helped buddies who have got into a problem, and also stopped incident pits escallating for buddies. One buddy in particular, Mark Reeves, has stopped several of my incident pits progressing even though we both dive solo often.

So all in all, I agree, many accidents can be avoided by diving in pairs, where the pairs are well matched.

Alex

ChemicalDiver · 23rd September 2007, 19:59

Having read most of the "CCR Fatality Statistics" thread, and some of this one, my question as a new future buyer and owner of an eCCR is the following (sorry if this is a hijack...) :

Assuming there are any fatalities even loosely related to the design of the rebreather, there must be several "close shaves" where that same bug or a malfunction was caught and solved quickly enough and did not lead to death.
So for each malfunction or design error to cause a fatality, should there not be an equal if not higher number of near misses (unless something truly catastrophic is the issue).

How do such close shaves compare across different units and do they bring up inherent drawbacks (even little ones) of one vs another rebreather design. I know there are already some different drawbacks and risks between SCRs mCCRs and eCCRs, so why not believe that between eCCRs this is also true. Should this not in time be reflected in "incidents", whether fatal or not. Much more interesting are those that were "very nearly fatal" as the story can be told.

I am not at all terribly convinced about this "all diver error or spontaneous heart attack" stuff. Sure, perhaps most fatalities are due to this but these must average out across units, yet the statistical numbers are different as has been asserted by others on this site, yet the type of diver and diving on each unit is relatively homogeneous and the number of heart attacks on whatever unit should be similar, given enough units in circulation and hours on them.
And whether a heart attack or other illness is the main cause of death is somewhat irrelevant and obvious to those that have decided to go rebreather diving or diving in general, it is what kind of incident (or death) is more likely on which rebreather that might be much more interesting ( and of course difficult to answer). The answer is not drowning

A unit that forgives a certain diver error versus another unit that punishes you by killing you is worthwhile info, regardless of diver error or not.
While we all strive to perfection in our diving, to err is human.

So for a future buyer, while I am keen on an lower WOB on say a Meg, I might favour a Boris if it is more "safe or forgiving", even if I intend to be a safety-nut on either unit.

Is this not the case with fighter jets for example. Some jets, would be very unforgiving to fly, but by and large only ever crash due to pilot error. Still those planes come down more often than others. The idea is not to justifying being a poor pilot, just having an extra fail safe.

Thanks for any comments,

Alex

**PhilSiswick** · 24th September 2007, 08:33

Quote: (Originally Posted by ChemicalDiver)

Having read most of the "CCR Fatality Statistics" thread, and some of this one, my question as a new future buyer and owner of an eCCR is the following (sorry if this is a hijack...) :

Assuming there are any fatalities even loosely related to the design of the rebreather, there must be several "close shaves" where that same bug or a malfunction was caught and solved quickly enough and did not lead to death.
So for each malfunction or design error to cause a fatality, should there not be an equal if not higher number of near misses (unless something truly catastrophic is the issue).

How do such close shaves compare across different units and do they bring up inherent drawbacks (even little ones) of one vs another rebreather design. I know there are already some different drawbacks and risks between SCRs mCCRs and eCCRs, so why not believe that between eCCRs this is also true. Should this not in time be reflected in "incidents", whether fatal or not. Much more interesting are those that were "very nearly fatal" as the story can be told.

I am not at all terribly convinced about this "all diver error or spontaneous heart attack" stuff. Sure, perhaps most fatalities are due to this but these must average out across units, yet the statistical numbers are different as has been asserted by others on this site, yet the type of diver and diving on each unit is relatively homogeneous and the number of heart attacks on whatever unit should be similar, given enough units in circulation and hours on them.
And whether a heart attack or other illness is the main cause of death is somewhat irrelevant and obvious to those that have decided to go rebreather diving or diving in general, it is what kind of incident (or death) is more likely on which rebreather that might be much more interesting ( and of course difficult to answer). The answer is not drowning

A unit that forgives a certain diver error versus another unit that punishes you by killing you is worthwhile info, regardless of diver error or not.
While we all strive to perfection in our diving, to err is human.

So for a future buyer, while I am keen on an lower WOB on say a Meg, I might favour a Boris if it is more "safe or forgiving", even if I intend to be a safety-nut on either unit.

Is this not the case with fighter jets for example. Some jets, would be very unforgiving to fly, but by and large only ever crash due to pilot error. Still those planes come down more often than others. The idea is not to justifying being a poor pilot, just having an extra fail safe.

Thanks for any comments,

Alex

Alex,

I certainly agree with you on this. You have to read between the lines of incident reports and experiences posted here to get that kind of analysis, but it is there to find.

Cheers,

Abbo · 25th September 2007, 06:42

When you get involved in an adventure sport you understand that you are taking your life in your hands. Surely the best way to stay alive in such an activity is to also take the responsibility in your hands. When something goes wrong it is my fault; that's not to say it can't also be somebody else's fault, but first and foremost it is my fault. Finding out the weak points and the peculiarities of my unit is my responsibility. I really didn't like the way that the CCR Fatality Statistics thread casts aspersions on makers, first because I don't think there is a shred of evidence that the equipment has been responsible for these deaths, and second because I think it is a dangerous way of thinking.

I wanted to start a thread that steered away from arguments about who's got the best toy and focus on how to make the unit I have as safe as possible. I am a little disappointed that few clear patterns have emerged, like "the most common mistake among Meg users is X" or "overall, the most common mistake is Y". Perhaps those that know don't say and those that say don't know. Could I change the question and ask
What are the most common causes of serious non-fatal accidents?

AD_ward9 · 25th September 2007, 06:50

Quote: (Originally Posted by Abbo)

What are the most common causes of serious non-fatal accidents?

The list is HERE.

Alex

Drmike · 25th September 2007, 10:03

Of course one sure way to reduce the number of rebreather deaths is to only use one if the benefits outway the risks (ie only if you need one)

deeply unpopular - but you know its true

IMO people that arent mosty doing overheads or sub 70m dives should not be diving a rebreather

(As the technology stands at the moment) cos you are far safer on OC.

So Id estimate thats 50% of users out there.

decoweenie · 25th September 2007, 10:29

Quote: (Originally Posted by Drmike)

So Id estimate thats 50% of users out there.

Everyone has an opinion, so I will toss mine in too...

I think 50% is a conservative mark.

Personally, I tend to think 70% of the Rebreather divers don't routinely dive past 70m.

**PhilSiswick** · 25th September 2007, 12:18

Quote: (Originally Posted by AD_ward9)

The list is HERE.

Alex

With respect, this doesn't help Abbo any further. I agree that all of these failures are possible, but which are more possible than others? Which ones are more fatal/dangerous than others? It's unlikely that anyone could take an existing unit and reengineer it to avoid all of these failures, so which are the key ones one would focus on?

Cheers,

22nd September 2007, 15:57	#41 (permalink)
Skipbreather Reads the fine print Current Rebreather/s: Megalodon Home Build Other Rebreather/s: Not Bought Yet MK 15.X Home Build Join Date: Mar 2005 Location: Chicago, Illinois, USA Posts: 555	Re: Statistics: main cause of death with rebreathers It took 4 pages but someone finally mentioned what I see as the root cause of most accidents: Loss of situational awareness. If a diver is on top of whatever aspects of the dive he can control, he will be ready for most non routine occurrences (malfunctions, oversights, whatever). It is vital to be AHEAD of what is going on, not just reacting to whatever situations develop. The loss can arise via many avenues. When new to CCR, folks won’t have the experience base to keep the big picture in mind- the basics monopolize most of their efforts. At the other end of the scale, complacency is a silky pillow that lures a highly experienced CCR diver to let his brain take a nap just when it’s needed most. Most dangerous time of all, IMVHO, is the intermediate stage CCR diver who has built a decent experience base but has not been at it long enough to have been challenged by critical stuff breaking at the worst possible time. His kit has served him well and all those dire things that his instructor drilled him on a year or two ago are becoming just dusty scary stories that only happen to “other” divers. He looses his situational awareness- he quits ‘what if-ing’- and when an unanticipated event starts developing he blows it off or, worse, does not even notice it and what was a minor ‘situation’ quickly becomes a full blown emergency (How did that drill go?). All mechanical things will break eventually. Dive site conditions are constantly changing. Humans forget stuff occasionally and are themselves breakable. The diver who works hard at staying in touch with all that is going on around him and anticipates- in short, has good situational awareness- has the best chance of not becoming a statistic. I'll climb off my soap box now...... __________________ "Entropy RULES! Enjoy the interim."
(Online)

23rd September 2007, 08:56	#42 (permalink)
teddy2005 New Member Current Rebreather/s: rEvo Other Rebreather/s: rEvo Join Date: Oct 2005 Location: Switzerland Posts: 34	Re: Statistics: main cause of death with rebreathers Quote: (Originally Posted by caveseeker7) Don't know what EDO-04 accident you refer to, but in at least one of them the one way valves to the smaller bellows were defect and not working. On both units of the dual Rebreather setup. That the diver wasn't properly trained and diving shallow water probably didn't help much, either, but those components of his RBs were not in working order. The state police of the area posted an anlysis and warning including pictures on their website, the damaged/faulty valves were clearly visible. The state police made this report based on a biaised analysis of the machine and before enquiries were conducted in depth. The valves were not involved in the accident. I was closely involved so I think I better know thant the first alarming threads which were dispatched...
(Online)

23rd September 2007, 19:42	#43 (permalink)
AD_ward9 So much more to learn Current Rebreather/s: Other CCR Other Rebreather/s: Other CCR Join Date: Jun 2005 Location: Scotland Posts: 1,856	Re: Statistics: main cause of death with rebreathers Quote: (Originally Posted by SteveJ) In deaths from 1997-2004, approximately 50% were diving solo. That's not a cause but it is a strong association. Probably 1% of sports diving is solo, by observation: I do not have any better data source on this. This means that if the 50% of deaths from solo diving is accurate, that is a very strong association. I for one have helped buddies who have got into a problem, and also stopped incident pits escallating for buddies. One buddy in particular, Mark Reeves, has stopped several of my incident pits progressing even though we both dive solo often. So all in all, I agree, many accidents can be avoided by diving in pairs, where the pairs are well matched. Alex
(Offline)

23rd September 2007, 19:59	#44 (permalink)
ChemicalDiver New Member Current Rebreather/s: Not Bought Yet Other Rebreather/s: Not Bought Yet Join Date: Dec 2006 Location: Switzerland Posts: 28	Re: Statistics: main cause of death with rebreathers Having read most of the "CCR Fatality Statistics" thread, and some of this one, my question as a new future buyer and owner of an eCCR is the following (sorry if this is a hijack...) : Assuming there are any fatalities even loosely related to the design of the rebreather, there must be several "close shaves" where that same bug or a malfunction was caught and solved quickly enough and did not lead to death. So for each malfunction or design error to cause a fatality, should there not be an equal if not higher number of near misses (unless something truly catastrophic is the issue). How do such close shaves compare across different units and do they bring up inherent drawbacks (even little ones) of one vs another rebreather design. I know there are already some different drawbacks and risks between SCRs mCCRs and eCCRs, so why not believe that between eCCRs this is also true. Should this not in time be reflected in "incidents", whether fatal or not. Much more interesting are those that were "very nearly fatal" as the story can be told. I am not at all terribly convinced about this "all diver error or spontaneous heart attack" stuff. Sure, perhaps most fatalities are due to this but these must average out across units, yet the statistical numbers are different as has been asserted by others on this site, yet the type of diver and diving on each unit is relatively homogeneous and the number of heart attacks on whatever unit should be similar, given enough units in circulation and hours on them. And whether a heart attack or other illness is the main cause of death is somewhat irrelevant and obvious to those that have decided to go rebreather diving or diving in general, it is what kind of incident (or death) is more likely on which rebreather that might be much more interesting ( and of course difficult to answer). The answer is not drowning A unit that forgives a certain diver error versus another unit that punishes you by killing you is worthwhile info, regardless of diver error or not. While we all strive to perfection in our diving, to err is human. So for a future buyer, while I am keen on an lower WOB on say a Meg, I might favour a Boris if it is more "safe or forgiving", even if I intend to be a safety-nut on either unit. Is this not the case with fighter jets for example. Some jets, would be very unforgiving to fly, but by and large only ever crash due to pilot error. Still those planes come down more often than others. The idea is not to justifying being a poor pilot, just having an extra fail safe. Thanks for any comments, Alex
(Offline)

24th September 2007, 08:33	#45 (permalink)
PhilSiswick Phil Siswick, Tango Current Rebreather/s: Evolution Other Rebreather/s: Inspiration Vision Join Date: Apr 2006 Location: Oxford, UK Posts: 991	Re: Statistics: main cause of death with rebreathers Quote: (Originally Posted by ChemicalDiver) Having read most of the "CCR Fatality Statistics" thread, and some of this one, my question as a new future buyer and owner of an eCCR is the following (sorry if this is a hijack...) : Assuming there are any fatalities even loosely related to the design of the rebreather, there must be several "close shaves" where that same bug or a malfunction was caught and solved quickly enough and did not lead to death. So for each malfunction or design error to cause a fatality, should there not be an equal if not higher number of near misses (unless something truly catastrophic is the issue). How do such close shaves compare across different units and do they bring up inherent drawbacks (even little ones) of one vs another rebreather design. I know there are already some different drawbacks and risks between SCRs mCCRs and eCCRs, so why not believe that between eCCRs this is also true. Should this not in time be reflected in "incidents", whether fatal or not. Much more interesting are those that were "very nearly fatal" as the story can be told. I am not at all terribly convinced about this "all diver error or spontaneous heart attack" stuff. Sure, perhaps most fatalities are due to this but these must average out across units, yet the statistical numbers are different as has been asserted by others on this site, yet the type of diver and diving on each unit is relatively homogeneous and the number of heart attacks on whatever unit should be similar, given enough units in circulation and hours on them. And whether a heart attack or other illness is the main cause of death is somewhat irrelevant and obvious to those that have decided to go rebreather diving or diving in general, it is what kind of incident (or death) is more likely on which rebreather that might be much more interesting ( and of course difficult to answer). The answer is not drowning A unit that forgives a certain diver error versus another unit that punishes you by killing you is worthwhile info, regardless of diver error or not. While we all strive to perfection in our diving, to err is human. So for a future buyer, while I am keen on an lower WOB on say a Meg, I might favour a Boris if it is more "safe or forgiving", even if I intend to be a safety-nut on either unit. Is this not the case with fighter jets for example. Some jets, would be very unforgiving to fly, but by and large only ever crash due to pilot error. Still those planes come down more often than others. The idea is not to justifying being a poor pilot, just having an extra fail safe. Thanks for any comments, Alex Alex, I certainly agree with you on this. You have to read between the lines of incident reports and experiences posted here to get that kind of analysis, but it is there to find. Cheers, __________________ Phil (WSKD 0001) I have always felt that the dive I am on is not nearly important as the dives I plan to be on the rest of my life. Tom Rose, 2007 The person who gets the farthest is generally the one who is willing to do and dare. The sure thing boat never gets far from shore. Charles A. Lindbergh www.hugsac.org.uk
(Online)

25th September 2007, 06:42	#46 (permalink)
Abbo Nicholas Smith Current Rebreather/s: Megalodon Other Rebreather/s: Join Date: Aug 2006 Location: Tokyo Posts: 449	Re: Statistics: main cause of death with rebreathers When you get involved in an adventure sport you understand that you are taking your life in your hands. Surely the best way to stay alive in such an activity is to also take the responsibility in your hands. When something goes wrong it is my fault; that's not to say it can't also be somebody else's fault, but first and foremost it is my fault. Finding out the weak points and the peculiarities of my unit is my responsibility. I really didn't like the way that the CCR Fatality Statistics thread casts aspersions on makers, first because I don't think there is a shred of evidence that the equipment has been responsible for these deaths, and second because I think it is a dangerous way of thinking. I wanted to start a thread that steered away from arguments about who's got the best toy and focus on how to make the unit I have as safe as possible. I am a little disappointed that few clear patterns have emerged, like "the most common mistake among Meg users is X" or "overall, the most common mistake is Y". Perhaps those that know don't say and those that say don't know. Could I change the question and ask What are the most common causes of serious non-fatal accidents?
(Offline)

25th September 2007, 06:50	#47 (permalink)
AD_ward9 So much more to learn Current Rebreather/s: Other CCR Other Rebreather/s: Other CCR Join Date: Jun 2005 Location: Scotland Posts: 1,856	Re: Statistics: main cause of death with rebreathers Quote: (Originally Posted by Abbo) What are the most common causes of serious non-fatal accidents? The list is HERE. Alex Last edited by AD_ward9 : 25th September 2007 at 08:49. Reason: Link
(Offline)

25th September 2007, 10:03	#48 (permalink)
Drmike Custom Title Allowed! Current Rebreather/s: MK 15.X Ouroboros Other CCR Home Build Other Rebreather/s: Inspiration Classic Other CCR Home Build Join Date: Feb 2005 Posts: 3,301	Re: Statistics: main cause of death with rebreathers Of course one sure way to reduce the number of rebreather deaths is to only use one if the benefits outway the risks (ie only if you need one) deeply unpopular - but you know its true IMO people that arent mosty doing overheads or sub 70m dives should not be diving a rebreather (As the technology stands at the moment) cos you are far safer on OC. So Id estimate thats 50% of users out there. __________________ Cave diving is a sport Wreck diving is a sport Diving in general is a sport 'Rebreather diving' is not a sport its the delusional obsession with a highly dangerous and often inappropriate piece of equipment Last edited by Drmike : 25th September 2007 at 10:07.
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25th September 2007, 10:29	#49 (permalink)
decoweenie Crash Test Dummy Current Rebreather/s: Other CCR Other Rebreather/s: Other CCR Join Date: Feb 2005 Location: Cairo Posts: 5,510	Re: Statistics: main cause of death with rebreathers Quote: (Originally Posted by Drmike) So Id estimate thats 50% of users out there. Everyone has an opinion, so I will toss mine in too... I think 50% is a conservative mark. Personally, I tend to think 70% of the Rebreather divers don't routinely dive past 70m. __________________ "...after a while you get bored offering advice to a bull that like to keep butting the fence with its head rather than walking through the open gate..." - Rebreather World PM
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25th September 2007, 12:18	#50 (permalink)
PhilSiswick Phil Siswick, Tango Current Rebreather/s: Evolution Other Rebreather/s: Inspiration Vision Join Date: Apr 2006 Location: Oxford, UK Posts: 991	Re: Statistics: main cause of death with rebreathers Quote: (Originally Posted by AD_ward9) The list is HERE. Alex With respect, this doesn't help Abbo any further. I agree that all of these failures are possible, but which are more possible than others? Which ones are more fatal/dangerous than others? It's unlikely that anyone could take an existing unit and reengineer it to avoid all of these failures, so which are the key ones one would focus on? Cheers, __________________ Phil (WSKD 0001) I have always felt that the dive I am on is not nearly important as the dives I plan to be on the rest of my life. Tom Rose, 2007 The person who gets the farthest is generally the one who is willing to do and dare. The sure thing boat never gets far from shore. Charles A. Lindbergh www.hugsac.org.uk
(Online)

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