Fatality at Jersey Island

[wedivebc]

Better if the mushroom valves can be easily visually inspected (i.e. as in the Poseidon 7, Golem Shrimp BOV, maybe others...) as part of the pre-dive assembly/check and if they are deformed or discoloured (the suck/blow test is not enough) replaced pre-dive (or replaced annually as routine)... provided then you cannot re-assemble the lot incorrectly.

No idea if in the deceased rebreather the one-way valves could be easily visually inspected (but HSL and the Coroner did not determine the one-way valves to be faulty).

To add automation and electronics when the task can be achieved more simply by simpler design features adds complexity and does not necessarily reduce risk.

Yes it is very easy to check the mushroom valves on a Hollis P2 and is part of the daily checklist to do so. But I thought we were busy designing a rebreather that was impervious to user error. Have you completely changed direction on this now?

 

[Dr. Lecter]

I have looked at the latest available manual on the Hollis website and still there is no reference or warning or user information... that the product does not meet Clause 5.1 of BS EN 14143:2013 (or its prior wording in BS EN 14143:2003), which states:

“It shall not be possible to assemble or combine the components or parts in such a way that it can affect the safe operation and safe use of the apparatus, e.g. by incorrect connection of the hoses to the breathing circuit.”

The language of the clause is meaningless, because there is no specificity about just how impossible misassembly must be, and if it truly meant what it said it would be violated by any system (whether on the market or merely theoretical). It's feel-good EU consumer protection BS, and as such merits no discussion by Hollis.

Now, the importance of assembling the DSV correctly is specific and is worthy of emphatic mention. And wouldn't you know it, it gets it.

 

[flots am]

The language of the clause is meaningless, because there is no specificity about just how impossible misassembly must be,

In industry, "impossible to connect wrong" is very common and I would expect them to use the commonly accepted standard. It is "impossible", for example, to connect a hydrogen cylinder to a CO2 hose.

This doesn't mean that some enterprising individual won't go down to Home Depot and cob together something out of lawn sprinkler parts and hose clamps and create exploding Diet Coke, just that it's impossible using the supplied components, which is good enough.

The standard has very clear meaning, and is quite usable for anybody not intent on subverting it.

flots.

 

[gianaameri]

It is not the first time this type of user errors (rebreather incorrect assembly) happen, and it wont' be the last.

See:

1. http://mkvi.poseidon.com/downloads/To_whom_it_may_concern_2013-04-26.pdf

2. https://www.divingincidents.org/incidents/149

The car industry used to be what the rebreather industry is now:

See: Unsafe At Any Speed -- The Designed-In Dangers of the American Automobile, by Ralph Nader

Even now the car industry is acting similarly to the rebreather industry:

See:

1. Toyota: We Lied About Acceleration Glitches, Twice

2. Honda underreported 1,729 claims of injuries or deaths since 2003

...and by all means, this is not meant to be an indictement of the rebreather industry - fudging, spinning, underreporting, obfuscation... is common in all businesses (banking, financial auditing...).

As consumer the lesson to be learned here - taking also into account in the very specific of this incident the inaction by U.K. Trading Standards and HSE despite the HSL and Coroner clear and publicised findings - is that we are on our own.

Rebreather buyer/user beware!

 

[gobfish1]

I'm not going to claim any expertise to determine how valid this is or isn't, but he goes into detail as to exactly why he says that here: Oxygen Toxicity and CCR Diving

DISCUSSION:
We found no general tendency to CO2 retention during decompression. It is plausible that breaching oxygen exposure limits during resting decompression is less hazardous than equivalent breaches when exercising at deep depths. Mitchell SJ, Mesley P, Hannam JA. End tidal CO2 in recreational rebreather divers on surfacing after decompression dives.

iv 30 year,s of Accelerated decompression to go off , but for others that dont lots of stuff to read , be4 you all make your minds up ,
have a read of what ppo2 the p party navy divers used when working , i say working no fanning about on a noddy dive ,

 

[gianaameri]

have a read of what ppo2 the p party navy divers used when working

Yes, and they do this shallow where the WOB of the equipment they use is low and they use quality equipment (WOB of the equipment increases with gas density and depth, all other things being equal, being shallow the equipment WOB is lower, than if they were deep, all other things being equal).

 

[gobfish1]

Yes, and they do this shallow where the WOB of the equipment they use is low and they use quality equipment (WOB of the equipment increases with gas density and depth, all other things being equal, being shallow the equipment WOB is lower, than if they were deep, all other things being equal).

yes you would hope that to be true , but back in 1942 i think not , looking at some of the kit used , im sure it was,nt so ,

after diving some years to 70m on air oc , and using nitrox / o2 on deco . then moving to ccr and a 10/50 dill , the wob on my old turd is nothing like sucking treacle toffee through my oc regs at 70m
all other things being equal

 

[gianaameri]

yes you would hope that to be true , but back in 1942 i think not , looking at some of the kit used , im sure it was,nt so ,

Acceptable fatality rates in military training in 1942 was 10% (and higher for underwater activities) and the fatality we are actually discussing happened in 2014 allegedly on EN14143 equipment PADI Type Approved (that is for all divers, noobs and not, well below the standard of military divers) - equipment which was supposedly not possible to assemble incorrectly such that it failed in a dangerous way - but it did and the diver died.

So, maybe we should stay on topic and focus on the Hollis Prism 2.

 

[gobfish1]

Acceptable fatality rates in military training in 1942 was 10% (and higher for underwater activities) and the fatality we are actually discussing happened in 2014 allegedly on EN14143 equipment PADI Type Approved (that is for all divers, noobs and not, well below the standard of military divers) - equipment which was supposedly not possible to assemble incorrectly such that it failed in a dangerous way - but it did and the diver died.

So, maybe we should stay on topic and focus on the Hollis Prism 2.

you maybe right , but i think if you have a read up on the p party work done you will see that none was lost , even with all the unexploded ordence they pulled out of the harbors and rivers

1942 amd 2015 ppo2 is still ppo2 m8 , en what ever was not knocking about as you point out ,


ps id bet you 99% of them p party divers did in 40 roll ups a day , lol













Your putting yout nose in , on a post that i posted to answer someone other than you , sorry

 

[gianaameri]

you maybe right , but i think if you have a read up on the p party work done you will see that none was lost

I think you are talking B.S. and you have little direct or indirect knowledge of military rebreather diving in 1942 or 2015 or in that range, but if you are not I am keen to learn something new.

Would you mind starting a separate thread and post the "work done" you are referring to back in 1942 or thereabouts - presumably you are referring to some statistics or science.

Equally, if what you are discussing is relevant to this thread, please post it here, but kindly also briefly explain why it is relevant (to help the Mods).