What I am missing - The use of rebreathers.

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I am one of the negativity guys who has never used one (although I have done plenty of dives with people on rebreathers).

For me it is pretty simple. Most of the people who die whilst diving are rookies or idiots (or both). But when an experienced and skilled diver dies, then 95% of the time they are on rebreathers (the other 5% are either trying to set world depth records or are in caves - something else I won't do). I read an article once (I may try and find it to post a link) that said in risk adjusted terms you are 800 times more likely to die on a rebreather than on open circuit.

Yes, yes, I know - I am absolutely certain that there are thousands are divers using rebreathers happily and safely. But for me, the risks are proven on a statistical basis and I'll pay what I have to pay for extra gas, and live with the noise of my bubbles.


---------- Post added September 2nd, 2015 at 08:49 AM ----------


YMMV.


1. Ken, I agree that there are instances where OC may be more appropriate than CCR. My point was that even though everybody regards CCR to deep diving, I am perfectly content and even prefer CCR over OC in shallow water.

2. Regarding "statistics" - there aren't any. Or better, there aren't any good ones. The paper YMMV is thinking about is that BS study from Fock. There are so many things wrong with it and got, rightfully so, slapped around. So citing statistics to make the argument against CCR is not valid. At least not at this time.

3. The comment: "Most of the people who die whilst diving are rookies or idiots (or both)" should be reconsidered and stricken in light of that we just lost a very dear OC diver, Lynn Flaherty also known as TSandM and I would not call her a rookie or idiot by any means!

4. Nobody keeps count as to how many lives have been saved on CCR! The collapsed cave, the lost diver, heck the divers that ran out of gas in the cave....etc., etc., etc.

CCR is not for everyone and not for everything. But please stop bashing the rebreather!
 
3. The comment: "Most of the people who die whilst diving are rookies or idiots (or both)" should be reconsidered and stricken in light of that we just lost a very dear OC diver, Lynn Flaherty also known as TSandM and I would not call her a rookie or idiot by any means!

As I have posted elsewhere, I would certainly agree with that. But I do think Lynne's case is the exception that proves the rule.

I certainly would not try to change anyone else's mind on rebreathers - we all make our own decisions. But we were asked for views, and so I presented my own firmly held ones.
 

I am one of the negativity guys who has never used one (although I have done plenty of dives with people on rebreathers).

For me it is pretty simple. Most of the people who die whilst diving are rookies or idiots (or both). But when an experienced and skilled diver dies, then 95% of the time they are on rebreathers (the other 5% are either trying to set world depth records or are in caves - something else I won't do). I read an article once (I may try and find it to post a link) that said in risk adjusted terms you are 800 times more likely to die on a rebreather than on open circuit.

Yes, yes, I know - I am absolutely certain that there are thousands are divers using rebreathers happily and safely. But for me, the risks are proven on a statistical basis and I'll pay what I have to pay for extra gas, and live with the noise of my bubbles.


---------- Post added September 2nd, 2015 at 08:49 AM ----------

Can't find the original article, but some pretty chunky stats to much the same effect in here: https://www.google.com/url?sa=t&rct...25.xls&usg=AFQjCNEQo_WPRQpe8giogPG4YMJM_jc7ag

Although it does concede that most rebreather deaths come back to operator error, for me that is just restating the point: these machines are such that even enormously experienced divers suffer from fatal operator errors.

YMMV.

Where did you get your numbers? 95% of experienced divers who die while diving are diving rebreathers? The other 5% are setting records or in caves? Come on....that's just not realistic.

The spreadsheet you link to is well known for being overly biased and in many cases just plain wrong. Several of the deaths that are attributed to unit design or malfunction were actually due to diver error or poor decisions by the diver before even getting in the water.

It has been said that the most dangerous time for a rebreather diver is when they have between 25 and 100 hours on the unit. The first 25 hours are usually done in a very cautious and careful manner. Checklists are followed, the units are usually new and nothing goes wrong. After those first 25 hours, some divers can become complacent. Checklists are abbreviated or skipped. Things start to go wrong, and due to inexperience in handling problems, problems can compound into serious and dangerous situations. When you get to 100 hours, you've probably survived some problems, you've learned that checklists and pre-dive checks are important after all, and the lessons you have learned have made you a more careful diver. This isn't to say that new rebreather divers and 100+ hour rebreather divers are exempt from dying on their unit. If you're not careful, any rebreather can be a dangerous piece of equipment.

Luckily for me I have been very fortunate. I have had the opportunity to learn from some of the best in the business in my opinion, and the lessons I've learned have made it possible for me to get to where I am today. I have definitely had problems arise during dives that might have been serious had it not been for my excellent instructors.

The biggest lesson I've learned is "When in doubt, bail out!" Nothing is ever lost by bailing out to a known good gas. Thumbing a dive when something does not "feel right" might make me miss a dive or two, but it lets me live to dive another day.

The right attitude towards safety, compliance with your training, and a regimen of always following your checklists when assembling your unit as well as your pre-dive checklists will minimize the dangers of diving a rebreather. Note that I didn't say eliminate...there's no way to completely eliminate the risks of diving a rebreather.

To each their own - if you're afraid of diving a rebreather, then by all means you should never dive one.
 
Where did you get your numbers? 95% of experienced divers who die while diving are diving rebreathers? The other 5% are setting records or in caves?

90% of Internet statistics are valid. The other 90% are made up by people that can't add.

In this case it is the latter; it was an imaginary and unrealistic statistic used for emphasis (hence the nice round number, not to mention the unfeasability of a defined statistical category like "experienced and skilled divers").

But I stand by the basic premise if not the hypothetical number - when you hear about a really good diver dying, there is a meaty chance that the role of a rebreather will be mentioned soon afterward. If that sounds anecdotal on my part it is because it is. But I never expected agreement from the pro-rebreather crowd. As I said, YMMV.

 

But I stand by the basic premise - when you hear about a really good diver dying, there is a meaty chance that the role of a rebreather will be mentioned soon afterward. If that sounds anecdotal on my part it is because it is. But I never expected agreement from the pro-rebreather crowd. As I said, YMMV.


Anecdotal and completely unsupported by any body of evidence that I've ever seen.

-Adrian
 
Anecdotal and completely unsupported by any body of evidence that I've ever seen.

-Adrian

Right, because there are no reliable statistics full stop. You do have some attempts from researchers at DAN which put rebreather diving at roughly five to 10 times more risky (
http://divermag.com/rebreather-diving-killing-them-softly/), and that is without accounting for the significantly greater skill of your average rebreather diver over your average open circuit diver.

But what you will never, ever, ever find is any kind of statistics that suggest rebreather diving is safer, or even as safe as open circuit. Those statistics similarly don't exist, but the difference is that they never will.
 
At Rebreather Forum 3.0 many things about diving rebreathers were discussed including the stats surrounding fatalities. A few things were agreed, and some suggestions were made for agencies and manufacturers in the hope of improving safety and triggering a drop in deaths attributed to CCRs (and SCRs). We, the rebreather community, may be experiencing a positive effect from all that chatter. Hard to say since there is no control and no scientific data. But I wanna believe things like RF 3.0 are making a difference: a good one.

Unfortunately, even that will not make rebreathers as easy to operate and as "safe" as open-circuit.

There have been and continue to be all manner of claims made about how much more dangerous/risky rebreathers are than open-circuit, but frankly, backing-up any claim with supporting statistical "evidence" is gonna draw disagreement because the stats are, colloquially speaking, mostly ****.

This I know and believe emphatically. Diving a CCR is way more complicated than diving OC. For example, I recently had to conduct the final dive of a CCR program (air-diluent) wearing a set of doubles. For the past six years or so, my OC diving has been in a sidemount rig... back issues. Not only did I not die, I was able to maintain my position in the water column, was able to back kick, maneuver without flapping my hands, achieve trim, operate the various knobs and levers, check tank pressure, workout turn pressure, etc., etc. It was as though I dive with doubles all the time. Try that on a CCR after a six-year absence and see what happens.

Also, a rebreather is a tool. Way more complex than a table saw or a hammer, but a tool nevertheless. Sometimes a rebreather is the best tool for the job. Sometimes it is the worst tool for the job. Mostly, its suitability falls into a big, wide, tall, grey area called personal preference. And that's OK. However, there is a problem: operating in that big, wide, tall, grey area requires common-sense since issues of personal safety require actual decisions to be made and best practices to be followed. It requires thought and circumspection.

And that's why I honestly believe that the issue with rebreathers has nothing to do with the rebreather and everything to do with the person running it... and of course, when there are as many variables as there are with people, nothing can be made "safe." No engineer, no instructor, no agency, no outside influence can adequately protect us from our own shortcomings.

Something to ponder... a rebreather is not trying to kill you... your attitude towards diving it might though.
 
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And that's why I honestly believe that the issue with rebreathers has nothing to do with the rebreather and everything to do with the person running it... and of course, when there are as many variables as there are with people, nothing can be made "safe." No engineer, no instructor, no agency, no outside influence can adequately protect us from our own shortcomings.

Bravo Steve. I agree completely. I think what bothers me so much about the naysayers is that they're so quick to jump on the bandwagon of blaming the tool when a rebreather diver suffers a fatality. "They were diving a rebreather and they died so it must be the rebreather's fault" seems to be the common refrain. Then statistics are fabricated or anecdotal evidence
Is bandied about like gospel, and the cycle of misinformation is perpetuated. It's frustrating to say the least.


-Adrian
 
+1 on Dopplers statement. OC will kill you just as easily as a RB. I have had a regulator fail at depth on OC, fortunately I had plenty of air in my other bottle. Statistics paint what ever picture you want them to and it is hard to really compare RB fatalities to OC fatalities. Do you compare all RB diving to all OC diving or just tech diving? How many lives have been saved because of RB? It is a tool, any tool used improperly can hurt you. All diving is dangerous OC and RB, RBs are just less forgiving than other tools to carless ness or errors in judgment.
 
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