Fatality at Jersey Island

[gianaameri]

With a BOV since the mushroom valves are in the BOV body and not the hose the airflow direction would change. Still making a complete pass through loop. WOB would just be incredibly hard through going reverse through the scrubber.

That would still be a dangerous failure.

So, it seems to me both DSV and BOV if reversed by mistake can make the unit unsafe (on the BOV it would be visually clearer to see it was reversed, possibly the exhaust will be on your mask?).

I have to say that I do not understand how reversing the flow in a HP2 would increase dramatically WOB, because I think that reversing the flow on my Meg which also has a radial would not impair WOB in any major way (pPO2 yes). There must be something unique with the HP2 design.

 

[tstormdiver]

I really learned something here! Thank you for clarifying, Highwing. My newer Prism2 has the "key way" on the DSV, my older unit did not, to memory. I typically do a longer Positive & negative pressure tests than is called for (an hour or 2 at a minimum). Only 1 time did I ever have trouble with the positive & negative tests, as a result of the O-rings on the "Acrylic Bucket" rolled out of their grooves. It would not hold either way.

 

[rongoodman]

1. It is very easy to confuse one counterlung for another

Since one counterlung has the OPV and the other the ADV, in addition to the chest straps which would be on the outsides of the counterlungs were they reversed, I don't understand how you can make this assertion.

 

[HIGHwing]

Define "subtly."

How long does the unit hold a negative pressure?

How long does it hold a positive pressure?

If you do a positive pressure test and submerge the DSV, will it show bubbles (i.e. fail a 6 meter buddy bubble check)?

The above data with a. the old and b. the new version?

P.S. I suspect she would have had already passed out by 6 meters, but I do not know if it is fact, something which would be interesting to find out, that is if they did a bubble-check.

My personal process is 2 minutes for each which is not sufficient to discover this error from the pos/neg test. I am getting a lot of emails, phone calls, private messages about this since my photo/video post. I was asked to reattempt the test because my results were said to be inaccurate as I failed to let the test run long enough. As it turns out the, pos/neg does indeed fail beyond the two minute mark. The problem with that is I did mistakenly pass the test as did the accident victim.

I do not have the new DSV, but Hollis did contact me based on this thread and offer to send me the new DSV today on the next shipping truck that leaves the factory.

But I told Hollis that I don't need it. No one does, really. If you have any exposed threads on a P2 the hoses are reversed - period. The critical hoses are keyed to the CLs. So basically if I have even one exposed thread anywhere, the unit fails end of story.

I'm not inspired to bathtub dive my P2 tonight, but if I get so inclined I'll post pics.

 

[gianaameri]

My personal process is 2 minutes for each which is not sufficient to discover this error from the pos/neg test. I am getting a lot of emails, phone calls, private messages about this since my photo/video post. I was asked to reattempt the test because my results were said to be inaccurate as I failed to let the test run long enough. As it turns out the, pos/neg does indeed fail beyond the two minute mark. The problem with that is I did mistakenly pass the test as did the accident victim.

I do not have the new DSV, but Hollis did contact me based on this thread and offer to send me the new DSV today on the next shipping truck that leaves the factory.

But I told Hollis that I don't need it. No one does, really. If you have any exposed threads on a P2 the hoses are reversed - period. The critical hoses are keyed to the CLs. So basically if I have even one exposed thread anywhere, the unit fails end of story.

I'm not inspired to bathtub dive my P2 tonight, but if I get so inclined I'll post pics.

You do not need the "new" DSV because just as the old it has the same problem.

The problem is that if installed in reverse like the deceased did it WILL kill you.

It is possible to make this mistake and for it to go unnoticed by a a qualified professional and trained user like Jillian Smith, and it fooled you (an "expert") too (at least till you did an overly long Pos. and Neg. pressure test and got a few emails and private messages).

Beats me how Hollis only decided to contact you and only you as a consequence of this thread, and did not issue a Safety Notice to its customer base and informed all its instructors about the importance to emphasise during training this one specific bit of problem which others (JIllian Smith) encountered and died because of it and because of the inevitable propensity of all divers as humans to make mistakes.

WTF?

No one deserves to die for a simple assembly error on a recreational dive - error which is easily preventable by left-hand and right-hand thread on the device such that the user cannot assemble the unit incorrectly.

 

[tstormdiver]

You do not need the "new" DSV because just as the old it has the same problem.

The problem is that if installed in reverse like the deceased did it WILL kill you.

Installed in reverse to the lower loop hoses WITH the counterlungs also installed in reverse

It is possible to make this mistake and for it to go unnoticed by a a qualified professional and trained user like Jillian Smith, and it fooled you (an "expert") too (at least till you did an overly long Pos. and Neg. pressure test and got a few emails and private messages).

I am by far no "expert" on the Prism2, I only have about 70 hrs on the unit, but I know in an instant the difference between the counterlungs (it is too obvious) & where the belong. I was taught,... no,... had it pounded in my head to pay absolute attention to what I am doing when working with the unit, not to have my head "you know where". Jill Heinerth basically said in a documantary she was in about CCR Cave diving, that, you must be very attentive when prepping & using a (any) rebreather, You have to assume it is trying to kill you at any time. I understand that most probably do (did) not get the slow (months), thorough training I received, with constant drilling about the unit & the dives. I told my instructor that I wanted to know the unit inside & out before ever getting it wet. He still, to this day, drills me about it with assembly, nitrox formulas for dives, possible issues & how to solve or troubleshoot them.

Beats me how Hollis only decided to contact you and only you as a consequence of this thread, and did not issue a Safety Notice to its customer base and informed all its instructors about the importance to emphasise during training this one specific bit of problem which others (JIllian Smith) encountered and died because of it and because of the inevitable propensity of all divers as humans to make mistakes.

My instructor emphasized that ANY mistake in assembly can be deadly & to keep my head screwed on straight when dealing with the unit. He also demands all check lists be adhered to EACH & EVERY time the unit is assembled for use. He has a deep mistrust of any rebreather & includes it in his training. I learned very quickly not to ever get in a hurry &/ or distracted when working with the unit. If I even think I am going to be in a hurry, I either just take the time regardless or I work on the unit at an earlier time when I will not be hurried. I keep my head in the game, or I do not dive the unit.

 

[gianaameri]

It is really no big deal for Hollis to improve on the design and have left and right hand thread to reduce the risk of user error and a repeat fatality.

Maybe something for Hollis Prism 3.

To deny that there is something to be learned from this fatality and something to be improved in the equipment and the training is reckless.

 

[Douglas Ward]

Jillian Smith died because she didn't follow her training. Not because of a design flaw or lack of adequate training materials.

The lesson to learn from her death is: Follow Your Training, Do your checklist, Double Check your assembly, and don't dive unless your are 110% confident everything is right.

 

[gianaameri]

Jillian Smith died because she didn't follow her training. Not because of a design flaw or lack of adequate training materials.

Maybe the instructor taught her wrong. We don't know that.

Maybe the check-list is not entirely that clear to her.

We do know that she died because she made some mistakes (a chain of errors) and the unit was not designed to prevent the user from assembling it wrong and fail dangerously.

BUT more importantly let us not forget she did a 5 minute pre-breathe in accordance to manufacturer instructions and training agency standard, and this served no purpose (i.e. was inadequate) to catch her prior errors and design weaknesses.

 

[Douglas Ward]

If she was taught that way, the instructor would be dead, as well as anyone he ever taught. Not possible.

If the checklist wasn't clear to her she shouldn't have gone diving.

Jillian Smith died because she didn't follow her training. Not because of a design flaw or lack of adequate training materials.

The lesson to learn from her death is: Follow Your Training, Do your checklist, Double Check your assembly, and don't dive unless your are 110% confident everything is right.