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

[berndo]

But…. there might be something to learn, or at least think about, to maybe prevent similar incidents when using off board diluent in a SM CCR configuration, if Gus’ incident was un-intentional. Such as discussing the pros and cons of using different mixes (i.e. deep helium mix on left / shallow non helium/high O2 deco mix on right) just to have a suitable dry suit (DS) gas source.

I'm not sure there is something to learn here. Don't bring air or nx to below it's MOD in a cave. AFIK that has been the SOP for a long time in cave diving. OC or CCR.

 

[Tracy]

I'm not sure there is something to learn here. Don't bring air or nx to below it's MOD in a cave. AFIK that has been the SOP for a long time in cave diving. OC or CCR.

And yet it is still done everyday. So maybe there is a lot to learn.

 

[berndo]

And yet it is still done everyday. So maybe there is a lot to learn.

Yeah, but what do you do about it. In the video Gus and Woody don't even acknowledge that they had been breaking a IMHO long established safety rules by bringing the gas. Someone asked about it on fb and they still argued that Gus's only mistake was plugging in the wrong gas. When they're not willing or able to see the obvious mistake, I don't know what else you can say or do.

 

[L13]

I have not confronted this yet in my diving, but is it a standard not to take gasses below their MOD?

It seems like a good rule in caves, where there is usually a good place on the way to the surface to stage the shallower gasses. But on other dives, it could be a real problem if you do not keep your shallow/deco gasses with you, since you may not follow a predictable path to the surface in an emergency.

 

[Tracy]

I have not confronted this yet in my diving, but is it a standard not to take gasses below their MOD?

It seems like a good rule in caves, where there is usually a good place on the way to the surface to stage the shallower gasses. But on other dives, it could be a real problem if you do not keep your shallow/deco gasses with you, since you may not follow a predictable path to the surface in an emergency.

It is a cave thing. You carry all gases on an OW dive. Most caves in the US only have one way in and one way out. Carrying the bottle for the whole dive increases workload and decreases safety.

 

[formernuke]

@Tracy

Thanks for clarification. Now it makes sense some the responses and how the incidents are related to each other.

 

[rjack321]

Gus was using 12/40 in his left bailout bottle with a second stage on a bungee around his neck, and air in his right bailout bottle with a second stage on a 7’ hose. Mike Y. posted on FB that air was in the right bottle so it could be used for dry suit inflation and deco.

I don't know what Gus' setup was, but one common Sidewinder setup is to have a high flow QC6 quick disconnect on the right bailout bottle that feed the MAV/ADV & a standard low pressure QD that feeds the drysuit; and a standard lp QD on the left bailout bottle to feed the wing. Gus stated in a DiveTalk video that he intentionally plugged the right bottle (air) quick disconnect into the MAV that fed the loop, and it wasn’t a mistake. But he goes no to state it was the first-time diving trimix on his Sidewinder and he didn’t realize air (right tank) was feeding the loop as the left bottle connects to the MAV and feds the loop on his Sprit CCR which he normally dives on trimx.

Would be interesting to know if his left bailout bottle also had a QC6 quick disconnect, and he thought he actually plugged in the left tank. Or if the left tank Dil QC6 was too short to reach the MAV, so the right tank was plugged in knowing it would be a “hot”, non-helium Dil. Really doesn’t matter, as there’s nothing new to learn about intentionally using a hot, low helium Dil well below its MOD (Eric’s incident and possibly Gus’).

But…. there might be something to learn, or at least think about, to maybe prevent similar incidents when using off board diluent in a SM CCR configuration, if Gus’ incident was un-intentional. Such as discussing the pros and cons of using different mixes (i.e. deep helium mix on left / shallow non helium/high O2 deco mix on right) just to have a suitable dry suit (DS) gas source.

Having all these different configurations and QC6s on all sorts of different gases is a serious issue for the sidewinder and any other CCR that potentially has a whole variety of gases to plug in either intentionally or "just in case". The only people that have a robust dil switch protocol are the RB80s divers. But they are coming from GUE Tech2 (its a prerequisite), diving as a robust team on identical units, and don't have o2 cells so they damn well better get every gas switch perfect. Although even they had an issue which resulted in a o2 toxicity failure at depth.

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.

 

[berndo]

I have not confronted this yet in my diving, but is it a standard not to take gasses below their MOD?

On a dive like they did I don't even see why you need to carry any shallow gas. You don't need to switch Dil and there was shallow BO staged in the cave.
Their setup was highly unusual in both cases I think. In Gus's case. Using only 1 first stage for Dil and BO leaves you with your pants down if or when that first stage craps out on you.
I don't think I'm talking 20/20 here. Both stories are weird to me.

Just FYI: I know nothing about either case other than what was said in the Video and what's in the report.

 

[DOBY]

Having all these different configurations and QC6s on all sorts of different gases is a serious issue for the sidewinder and any other CCR that potentially has a whole variety of gases to plug in either intentionally or "just in case". The only people that have a robust dil switch protocol are the RB80s divers. But they are coming from GUE Tech2 (its a prerequisite), diving as a robust team on identical units, and don't have o2 cells so they damn well better get every gas switch perfect. Although even they had an issue which resulted in a o2 toxicity failure at depth.

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.

Very, very, eloquently spoken…..

 

[berndo]

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.

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