Rebreather Discussion from Brockville Incident

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Oh, you mean it's an old argument that G rotates through different RB forums. It's just new to SB. Tks.
 
Yah, right up until he gets banned.
 
I would like to reiterate the question already asked: Why are rebreather folks so defensive?

I know that my OC gear can malfunction. Most of the time, it will do so in a way that it loses gas I need to breathe. I have spare gas with me. Rarely, it will stop delivering gas that I have planned to use. I have spare gas with me. I will know immediately if my gear is losing gas, or refusing to deliver gas, and I will not be disabled while trying to solve the problem.

Rebreathers have multiple failure modes. They can deliver too much oxygen, which is something that often has no symptoms until you seize. It can deliver too LITTLE oxygen, something which has no symptoms until you lose consciousness. It can deliver too much CO2, something for which you have no instrumentation, and which manifests initially as anxiety, and then as confusion, obtundation, and loss of consciousness. It can flood and deliver a caustic cocktail to your mouth and pharynx. Many of those failure modes will disable a diver at about the same time as he realizes that the problem exists.

I do think rebreathers can be dived with acceptable safety, if the unit is set up to be safe, and if the diver is meticulous, methodical, and disciplined. The current push to get rebreathers into the hands of the general diving population is selecting for none of those attributes.
 
This is the part that you need to provide references for. Everyone can google the documents you refer to.

You're saying that currently available rebreathers have been certified to meet EN14143:2003 even though their electrical/electronic parts either haven't been properly tested under IEC 61508, or have been tested and failed the test, and that everybody knows about this but nobody does anything about it, while at the same time there are no publicly available sources to testify that.

The moon landing was staged too, right?

No, I do not think the moon landing was staged, but blunders happen all the times.

There was a blunder a long time ago and some Notified Body (i.e. a test house/certification agency) issued a two page certificate where the first page could be interpreted one way, and the second page a different way. This led some manufacturer in error and in good faith to mark and sell products as "EN14143:2003" - but in reality the Notified Body never intended to certify it to "EN14143:2003" because the product did not meet Clause 5.13.1 insofar the product had a "SIL Level of less than 1" (SIL 1 is the minimum level to achieve Functional Safety, with SIL 4 being the highest and safest level of Functional Safety).

That is what the Freedom of Information documents I obtained show. They are available to all who make a Freedom of Information request to the U.K. authorities.

So, lots of these products get sold and people start dropping dead (bear in mind that because of the dynamics of rebreather fatalities it is not possible to establish causation, people pass out and drown and the autopsy can only ascertain the drowning as the cause of death - so in no way I am suggesting the rebreather is the cause of the fatality!!!).

Years later the blunder gets caught, but it is kind of late insofar lots of rebreathers have been sold by now and it has become the de facto standard that these machines can actually be released to the general public despite lacking Functional Safety (i.e. being "less than SIL 1").

The issue is then what to do about the situation (in the meantime more and more people are dropping dead, but these machines make good money for a lot of people and a promising industry has developed).

The solution which is being adopted is to create a new standard which removes precisely the requirement which the machines do not meet, and sell more of these machines to a larger number of users.

It is consumerism and the profit motive is taking precedent over any other consideration.

We have now 289 recorded fatalities across a range of machines which all lack Functional Safety (not for lack of trying hard on the part of manufacturers) because the technology is not there yet (O2 galvanic sensors and cheap electronics in a corrosive environment and the inability of the human to detect bad gas before passing out is not exactly conducive to Functional Safety) and we are putting them in the hands of more recreational divers...

I think what is happening will become a Harvard Business School Case Study.

We can only hope in the meantime that some new technology advancement will come soon and rebreathers can be made safer than they currently are because the greater the adoption rate, the greater will be the number of fatalities (whatever the "cause" may be).

Read the reference documents I posted (post 51) and you will get a better understanding as to why where Human Factors (i.e. human error) is implicated then Functional Safety is key to reduce fatalities.

In the meantime we can collect the stats. and time will tell.
 
So when a guy intoxicated at a party builds his recreational unit and jumps in his pool and dies, it's the units fault. When another completely ignores that his unit failed the calibration process multiple times but dives it anyway, it's the units fault. When another fails to use an assembly check list and jumps in the water without the scrubber, it's the units fault. I guess if I die in a car accident because I failed to wear a seatbelt it's the car's fault. Come on! Lets take some responsibility here.
 
That is what the Freedom of Information documents I obtained show. They are available to all who make a Freedom of Information request to the U.K. authorities.

In Canada, when people make requests for Freedom of Information documents to prove some point, and these documents are granted, it is customary for the person(s) who made the request to publish what they found for all to see. Perhaps you can do the same. Otherwise it just seems to be an unsubstantiated claim.
 
I would like to reiterate the question already asked: Why are rebreather folks so defensive?

I'm not. I know that my RB has some issues that OC doesn't. I know that when I dive OC there are some issues that I don't have with my RB.

I also know that my RB isn't as deadly as some make it to be nor as safe as others make it to be.
 
In Canada, when people make requests for Freedom of Information documents to prove some point, and these documents are granted, it is customary for the person(s) who made the request to publish what they found for all to see. Perhaps you can do the same. Otherwise it just seems to be an unsubstantiated claim.

In the U.K., responsibility for these type of disclosures (i.e. lack of Functional Safety in accordance to Clause 5.13.1 of EN14143:2003) rests solely and exclusively with the manufacturer. So, it is a little different than in Canada.

On the bigger picture of things, I might publish something after the new rebreather standard EN14143:2013 (I presume it will be so called) is released by CEN/CENELEC.

All documents are in any event accessible through a FOI request. Best to address any request a. directly to the U.K. Secretary of State who is in charge of the U.K. National Authority in respect of implementation of EU Directives and CEN/CENELEC standards like EN14143:2003 and b. to the Local Government Ombudsman.
 
https://www.shearwater.com/products/swift/

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