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I actually bothered to read through the standard, and I looked at 5.13.1, which basically refers to 61508 Parts 1 & 2. After reading through the industry comments/objections, which were all dismissed flatly by the standards body, there are a few interesting points.
Obviously, the standards body treated/categorized the risk of rebreathers as exceedingly high despite not actually saying it. In fact, the parallel industries selected were Space Exploration, Aeronautics, and Nuclear Power which apparently apply the Functional Safety Clause, i.e. standards (though no evidence is provided in the comments). I've also concluded these standards as applied are not preventing space travel/rocket accidents, aircraft design errors exist causing total loss of airliners, and nuclear power plants and not operating with a flawless safety record.
By reading through all the stuff you posted as well as the available items I can find online, there are accidents despite standards; there are bad behaviors despite good training. I then looked at rebreather accidents, namely the MKVI. It appears the machine really isn't implicated in the four out of five regularly studied accidents with the fourth being undetermined causation.
There comes a point when we have to accept the activity we're participating is beyond the cutting edge. Though it seems far-fetched until I looked at the standards you constantly quote, I wouldn't have compared a rebreather dive to the Apollo space program, but I bet the Apollo Program wasn't ISO 9001 compliant. At some point discovery exceeds "safe" as defined by some body of "experts", perhaps even "Functional Safety". If people want to lay their lives on the line to find a new species of non-sighted crayfish in a solution tube in the Bahamas, be happy for them.
I think it's interesting that rebreather standards for "functional safety" are in effect derived from other very technical industries. What people should take away from this is to achieve the standard; it requires exceeding the bounds of currenlty available science. The APOC iCCR is an excellent example. Here is a rebreather that strives to do everything for everyone and meet every safety standard. The APOC is basically going to end up subject of a bunch of lawsuits, never delivered, and never dove. It's a fantasy by someone who assumed the answers to the science challenges were just around the corner and they weren't.
I know you were run off the CCRExplorers board in May for posting it's not safe a 1.5 million times, but I have to ask. Aren't you just making a very obvious point? I mean seriously, there's no one visiting this thread that doesn't understand a rebreather is not the most appropriate tool for every dive, nor every enviroment. Dismissing the Hollis Explorer, the vast majority of divers transitioning to a rebreather have OC experience, i.e. diving experience and have some knowledge about rebreathers before getting on the loop. So what exactly do you really think you're revealing? A standard that is beyond the edge of science is not being achieved? That's not breaking news in any industry.
I kinda wish I hadn't read through all of it because you had more credence with me before I did the research you suggested. I feel like stating the obvious isn't really adding value at this point. While your final statement is a bit cheeky, you probably should refocus it. It's not so much that we should get used to diving dangerous rebreathers, it's that we should adjust our behavior and increase our discipline to meet the demands/address the vulnerabilities of the available technology. In essence OC SCUBA will kill you on every dive if you do not modify your human behavior. You wouldn't ascend from 130/40M after taking inhaling a whole lung full of gas and holding it would you? Probably only once. I think the answer for right now is at the diver level. The science will come in time.
I stopped posting on CCRX because I got annoyed with a Moderator cutting and pasting my threads/posts. I was not "run off."
I was the subject of personal insults and threats of violence by the owner of another internet forum. That is a private matter.
On another forum (posts all public there) I was met with incredible hostility by a small number of users (same ones who were very hostile towards the APOC manufacturer). You could say "I was run off."
Here I think it seems a fairly balanced place to have an open discussion.
Now that we got the above out of the way (your comments required a balanced response), I am not sure what you are trying to say with your post in respect to the topic of discussion.
The fact is that the standard EN14143:2003 requires rebreathers not to exceed a maximum Probability of a Dangerous Failure.
This maximum Probability of Failure is defined in the international standard IEC61508 called upon by Clause 5.13.1 of EN14143:2003.
CE Certifications do not disclose that rebreathers are "less than SIL 1" and do not meet Clause 5.13.1 of EN14143:2003 which means the Probability of a Dangerous Failure exceeds that which the standard requires.
If you look at the Functional Safety standards for other apparatus (i.e. airplanes, medical devices...) they all have a numerical value which sets the maximum Probability of Failure that the user should be exposed to.
None set a ZERO Probability of Failure as target, but all set a numerical maximum Probability of Failure.
This number is generally aligned with what in a modern society we consider as acceptable risk.
Rebreathers exceed the acceptable risk threshold limit. The math tells us rebreathers are dangerous (so do the fatalities numbers and stats.).
Now, an O2 rebreather with front mounted counterlungs of a modern design would probably be relatively safe. We know military use has achieved zero fatality rates on these rebreathers.
Add galvanic O2 Sensors and electronics and take them beyond 6 meters - technology to date does not allow manufacturers to produce a safe rebreather.
If we use them, we do so at our own risk, but marketed as they are, with the true risks being obscured, the user cannot provide his "informed consent" because he/she is less than fully informed.
I am PRO rebreather use. I am against obscuring its true risks.
Why obscure the risks when you could just explain in clear terms aspects like CO2 Retention and the inability of electronics and software to protect the user from hypercapnia, hypoxia, and hyperoxia to a "SIL 1 or better" level?
