Virginian diver dead at 190 feet - Roaring River State Park, Missouri

[rjack321]

Is it normal for people to do a Dil switch on a 200' or 250' dive like this?

Not in a conventional backmount unit (revo, xccr, meg, fathom etc) with o2 in a 2-3L onboard bottle and dil in either a backmounted 2-3L or onboarded in 2x 50s/7s

The sidewinder and related sidemount CCRs have created some unusual and atypical habits. ~5 years after their explosion in popularity, we are seeing some of the hazards of the "make it up as you go" sidemount CCR universe. With so many configuration options and choices leading to a lack of standard training and missing fundamentals (like verified gas switches).

 

[Manatee Diver]

On every other unit, people are making it up QC6 dil switch /plug in protocols as they go. They are not officially taught in any other CCR class or cross-over. If you have identical left and right deep gases in the sidewinder and drop any additional gases at their MOD, then the holes in the QC6 cheese are fundamentally prevented from aligning. If you carry offboard or onboard gases below their MOD without a rigorous QC6 protocol then you are rolling the dice.

That is something I brought up earlier in this thread, when we were talking about Gus's incident. What are the offboard dil gas switch protocols? Do we need to formulate a standard for that? Though without getting, KISS, Fathom, and a major certification onboard it would be like herding cats, like the oxygen cut offs.

 

[rjack321]

That is something I brought up earlier in this thread, when we were talking about Gus's incident. What are the offboard dil gas switch protocols? Do we need to formulate a standard for that? Though without getting, KISS, Fathom, and a major certification onboard it would be like herding cats, like the oxygen cut offs.

Yup I pointed this out many posts ago. Yes the onboard tanks seem to be mis-analyzed at 24 instead of 26. That points to an issue with an analyzer. But, Eric wasn't some crazy fool diving EAN26 dil at >150ft. He had suitable diluent gases on him - the ones he was intending to drop at 190ft. This fatality seems to be at it's core a gas switch mistake.

The RB80 folks treat every QC6 plug in like a 2nd stage regulator switch and verify that the QC6 in their hand leads to the correct cylinder & MOD with buddy verification. The easier approach to CCRs like the sidewinder , genesis, and any other unit which relies on plugging in diluent, is to resist the temptation to add QC6s for all those gases. If you're doing a 21/35 dil dive with 50% for BO deco do you really need a QC6 on that 50% gas? Only if you add QC6s to your BO gases do you then need to develop ways to verify those switches. I swear I see a 100x more QC6 posts and adverstisments since units like the sidewinder became popular ~5 years ago. People need to stop adding QC6s because its cool and you can - they can also kill you.

 

[Tracy]

The RB80 folks treat every QC6 plug in like a 2nd stage regulator switch and verify that the QC6 in their hand leads to the correct cylinder & MOD with buddy verification. The easier approach to CCRs like the sidewinder , genesis, and any other unit which relies on plugging in diluent, is to resist the temptation to add QC6s for all those gases. If you're doing a 21/35 dil dive with 50% for BO deco do you really need a QC6 on that 50% gas? Only if you add QC6s to your BO gases do you then need to develop ways to verify those switches. I swear I see a 100x more QC6 posts and adverstisments since units like the sidewinder became popular ~5 years ago. People need to stop adding QC6s because its cool and you can - they can also kill you.

A good instructor teaches that every gas switch is a gas switch. Doesn't matter if it is a second stage or a qc6, you are still performing a gas switch and it should follow proper gas switching protocols.
Second stages can kill you just as easily. I see it as a training issue, not a gear issue.

 

[Manatee Diver]

This fatality seems to be at it's core a gas switch mistake.

In the case of Eric I'm not so sure, because why wouldn't be had that dil inputted in his computer?

Unfortunately we can't ask Eric why, so I am inclined he purposely dove that 24% tank. I personally blame Eric's death on his own errors, but team confirmation of gases would've caught it.

 

[berndo]

This fatality seems to be at it's core a gas switch mistake.

What about the computer being set to nx24 or nx26 though?

 

[rjack321]

A good instructor teaches that every gas switch is a gas switch. Doesn't matter if it is a second stage or a qc6, you are still performing a gas switch and it should follow proper gas switching protocols.
Second stages can kill you just as easily. I see it as a training issue, not a gear issue.

I'm fairly certain that people are adding QC6s to BOs because they can and to cover "contingencies". Without realizing that they were never taught, and their buddies aren't confirming every QC6 plug in. The absence of something - in this case the absence of a QC6 plug in protocol cause they are actually finishing assembly of the unit standing in the basin - isn't especially obvious. Compared to deviating from something which is actually taught. I don't know a single person on a sidewinder who was taught to verify the QC6 they are plugging in. In fact its almost impossible to do so in many cases because the male side coming off the right hand tank is only ~8" long.

 

[rjack321]

What about the computer being set to nx24 or nx26 though?

That setting is quite possibly leftover from the previous dive. Along with the EAN24/26 still being plugged in. I often wear 2 shearwaters and once or twice forgot to change the dil in the standalone unit. It's not that crazy of a mistake.

 

[Tracy]

I'm fairly certain that people are adding QC6s to BOs because they can and to cover "contingencies". Without realizing that they were never taught, and their buddies aren't confirming every QC6 plug in. The absence of something - in this case the absence of a QC6 plug in protocol cause they are actually finishing assembly of the unit standing in the basin - isn't especially obvious. Compared to deviating from something which is actually taught. I don't know a single person on a sidewinder who was taught to verify the QC6 they are plugging in. In fact its almost impossible to do so in many cases because the male side coming off the right hand tank is only ~8" long.

And people make deco gas switches everyday without going through gas switch protocols.
Is it stupid? Yes it is, but people continue to do it.
Again, I don't see how it has anything to do with the fitting. What difference does hose length make? You close the valve and push the purge, if the gauge drops, you are holding the correct fitting. If you can't reach the fitting to purge it, you aren't plugging it in either.

 

[rjack321]

And people make deco gas switches everyday without going through gas switch protocols.
Is it stupid? Yes it is, but people continue to do it.
Again, I don't see how it has anything to do with the fitting. What difference does hose length make? You close the valve and push the purge, if the gauge drops, you are holding the correct fitting. If you can't reach the fitting to purge it, you aren't plugging it in either.

It's not just the QC6 by itself, its how it is used by the sidewinder and similar units as part of a system (or lack thereof).

1) You typically finish assembly of the sidewinder and plug in the dil in the water. There's no bench assembly check of the dil like on a typical backmount CCR
2) You can't trace the hose from tip to 1st stage if its short and buried in your armpit. Heck some people don't even use gauges on their cave BOs.
3) The left/right side SM tanks are "backgas" and rarely even labelled with a MOD.
4) On CCR especially there are all sorts of different definitions of MOD for BO (or BO/dil), eg some treat 21/35 as a 150ft gas, to some its 190ft, to some its 218ft. It's hard to know how the EAN24/26 was even being treated MOD-wise.

Once you start adding additional BO or deco tanks with a variety of gases and MODs it's a problem on units like this if those tanks also have QC6s on them "just in case" you want to plug them into your CCR. If they don't have QC6s the only way to accidentally breath them is through the 2nd stage which people naturally understand as a risk. There are legions of threads here on how people add gear like QC6s "just in case". They are not viewed as a hazard. In this case they were a big hazard because the rest of the sidewinder system and related training isn't set up to address having 2+ QC6s on you. Unlike the RB80 folks starting off from day1 with qc6s as unit gas switches drilled into them.