Why so many deaths on CCR?

[Jax]

"At issue is poor initial instruction, diver complacency and a community ethos that sanctions or at least ignores bad habits and sloppy procedures."

Doesn't help when CCR divers die and those close to the accident know that "bad habits and sloppy procedures" might have been at fault and nobody speaks up.

How often would one need to dive a rebreather to remain "proficient"?

 

[Jax]

Thanks for that blog post, Steve.

I'm one of those who never dived a CCR, but know a bit about how they work.

What I find disturbing is how some of the most experienced and trained technical divers on the planet can become water temperature on the bottom of the ocean and many people just shrug it off and call it "operator error."

Also disturbing is that some survivors report that they knew exactly what happened, what needed to be done, what was happening to their body, but they simply could not bail out. Something gets lost between the brain and motor skills.

Clearly, something needs to be reviewed. Be it making the design more "idiot proof" (the accident with the scrubber mis-installed comes to mind), or taking a different approach to monitoring the loop (the lack of CO2 monitoring and the fact that sometimes 3 O2 cells aren't enough), I don't know. But to continue blame these deaths on operator error fails to recognize failures in the whole process, whether a problem in training, design, hardware, or software.

I cannot speak to CCRs, but I can discuss the "diver" (or human error) part.

Every time there is an accident or incident in the military - defined as anything that takes a soldier off duy (to go to the clinic) or damages equipment, there is some sort of investigation. These are the constant issues that are pounded into Army leadership over and over.

First - you cannot make anything idiot-proof . . . they just come up with better idiots. (Also, if you make something fool-proof, only a fool will want to use it.)

2nd . . . training, ergo the operator, should recognize the problem in design, hardware, or software, and react appropriately.

3rd . . . the reason the operator does not react appropriately may usually be attributed to carelessness (cavalier attitude) that interferes with the operator noting that something isn't quite right. Maybe s/he partied too much the night before, maybe s/he is sick that day, but not so sick to call off the work / dive. It still may be summed up to the operator failing to have the appropriate mental attitude to the work. Kind of like the drunk driver who gets away with it, and keeps doing it, but sooner or later driving drunk will catch up with you.

Sooner or later, sloppiness and cavalier 'tude will catch up with you. Nature abhors a vacuum and when that vacuum occurs in the brain, you will pay for it.

A simple example: Outside of every Military Police station is a barrel of sand sitting at a 45 degree angle. Every cop, every duty day, will unload their weapon and dry fire it into the barrel. Every duty day, s/he follows the prescribed routine. Why, then, does a round get discharged about 2-3 times a year?

Operator error. A cavalier attitude and sloppiness in the procedures.

 

[laurin]

One of the important points I was trying to make.

The general attitude in a part of the tech community has become one of lessez faire. Any aspect of self-policing seems to be lost. Buddies let buddies dive with sub-standard gear. The dive team concept is being ignored. And people who have no business being in the water let alone on a complex dive, are doing trust-me , skin of the teeth dives to the back of beyond.

At least, this seems to be what is happening with CCRs.

Do you feel that this is happening more with CCR divers compared to OC, or that the lack of self-policing is just having a more direct and serious consequences on CCRs?

Although I haven't been diving during 90's I'm getting the feeling that we're having a kind of a bounce to the other extreme of "anything goes" from the GI3-style overly confrontational days, combined with a better availability of information on internet and the push of big seriously profit driven agencies to the tech training market. And of course, the reintroduction of the "recreational rebreather".

Or is this just about a lack of a commonly accepted norm on CCR, compared to the Hogarthian approach on OC?

//LN

 

[dannobee]

I cannot speak to CCRs, but I can discuss the "diver" (or human error) part.

Every time there is an accident or incident in the military...

Operator error. A cavalier attitude and sloppiness in the procedures.

Point taken.

But let's throw in the variable of a weapon system that fails in the heat of the battle, then disappears into the ocean and much of the evidence needed for a proper analysis is now gone. The soldier would likely take the heat for not following proper procedures when the equipment is the root of the problem.

 

[Rhone Man]

Three things I think that I think:

• I am guessing you will never hear about military deaths on rebreathers. Ever. That is the way the military is.
• I think the problems with rebreather deaths will get worse before it gets better. In the UK now CCRs can be purchased for as little as two and a half thousand pounds. More availability means more users and less experienced users. You know where that leads.
• There is a very interesting article which I read before I started this thread (900 times more deadly than OC? - article linked in the thread) that essentially points out what dannobee said above: it is not just that a lot of people die - a lot of really good people die.

 

[MXGratefulDiver]

One of the important points I was trying to make.

The general attitude in a part of the tech community has become one of lessez faire. Any aspect of self-policing seems to be lost. Buddies let buddies dive with sub-standard gear. The dive team concept is being ignored. And people who have no business being in the water let alone on a complex dive, are doing trust-me , skin of the teeth dives to the back of beyond.

At least, this seems to be what is happening with CCRs.

Several of the threads I've seen recently suggest the same thing is happening on recreational open circuit. Divers with less than 25 dives are going solo, or doing dives below recreational depths ... often on single tanks with inadequate or no redundancy and few clues about the risks they haven't prepared for.

What worries me more than the fact that they seem to think this is something to be proud of is the encouragement they sometimes receive from people who should know better ... I think it "sets the stage" for the mental approach these same divers take when they venture into technical diving ...

... Bob (Grateful Diver)

 

[Doppler]

Do you feel that this is happening more with CCR divers compared to OC, or that the lack of self-policing is just having a more direct and serious consequences on CCRs?


//LN

Pure speculation because I currently have no data to back it up but I believe that both OC and CCR teams have procedural issues but that the consequences are more direct and serious with regards CCR.

Although I haven't been diving during 90's I'm getting the feeling that we're having a kind of a bounce to the other extreme of "anything goes" from the GI3-style overly confrontational days, combined with a better availability of information on internet and the push of big seriously profit driven agencies to the tech training market. And of course, the reintroduction of the "recreational rebreather".

Or is this just about a lack of a commonly accepted norm on CCR, compared to the Hogarthian approach on OC?

//LN

A lot is things there and most I really have either incomplete or no data on at all.

 

[Doppler]

How often would one need to dive a rebreather to remain "proficient"?

Hey Jax: great question and I hope my answer makes sense, but of course it's based purely on personal comfort and opinion!

To begin with,many CCR instructors will not start a beginner's level CCR class with people who have not purchased a machine. For example my partner and I will rent units for level one/level one plus classes, but really only to folks who 1) have committed to a Pelagian and are waiting for it to be delivered (it can take up to three weeks) 2) are doing a crossover from another unit and may have a unit on order 3) are doing a provisional course.**

The connotation here of course is that to stay sharp on a CCR requires regular use. No point training on something you will not get practice on.

Some things to consider before even thinking about CCR. If you are a "binge diver" -- someone who really only dives for a couple of weeks while away on vacation but is inactive for most of the year -- CCR is not the best tool for you. If your mates all dive OC single tank and your favorite dive site is a local quarry, CCR may not be the best investment. If you take off your dive gear and often do not bother to rinse it and put it away neatly, CCR diving is going to be a challenge.

If on the other hand, you dive a few times a month, are detail oriented, dive cold water, burn through a lot of helium every year... CCR may be a useful tool to have in the kit.




** A provisional course is a full user-level class complete but at the end, we "hold the card." When they do buy a unit (if it's not with a few weeks of the course), we give them a refresher course (one or two days) and then release the card.

 

[Kevin Carlisle]

Hey Jax: great question and I hope my answer makes sense, but of course it's based purely on personal comfort and opinion!

To begin with,many CCR instructors will not start a beginner's level CCR class with people who have not purchased a machine. For example my partner and I will rent units for level one/level one plus classes, but really only to folks who 1) have committed to a Pelagian and are waiting for it to be delivered (it can take up to three weeks) 2) are doing a crossover from another unit and may have a unit on order 3) are doing a provisional course.**

The connotation here of course is that to stay sharp on a CCR requires regular use. No point training on something you will not get practice on.

Some things to consider before even thinking about CCR. If you are a "binge diver" -- someone who really only dives for a couple of weeks while away on vacation but is inactive for most of the year -- CCR is not the best tool for you. If your mates all dive OC single tank and your favorite dive site is a local quarry, CCR may not be the best investment. If you take off your dive gear and often do not bother to rinse it and put it away neatly, CCR diving is going to be a challenge.

If on the other hand, you dive a few times a month, are detail oriented, dive cold water, burn through a lot of helium every year... CCR may be a useful tool to have in the kit.




** A provisional course is a full user-level class complete but at the end, we "hold the card." When they do buy a unit (if it's not with a few weeks of the course), we give them a refresher course (one or two days) and then release the card.

Makes a lot of sense to me. I am glad you posted that. I have seen you dive both OC and CCR at JB. You are very meticulous, I know CCR is not for me. They scare me and am not afraid to say it. If was to do it, I would chose you as the instructor. As long as I didnt have to go up to that cold water where you live

 

[Matt S.]

Can someone summarize how people typically die on rebreathers?

My impressions are as follows, but I do not know if I am correct.

0. CO2 issues related to maintenance of the scrubber get you.
1. The operator fails to keep his PPO2 correct (manual unit)
2. Bad sensors give the operator or magical mixing computer false information about PPO2
3. Way down the list would be other mechanical failures not related to gas mixing, eg floods, which are not properly handled

In rebreather deaths, is it more common for the unit to fail you, and knock you out or make you tox... or is it more common for the user to make errors?