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

[tursiops]

extraordinarily asinine.

Now we are getting close....

 

[formernuke]

We will never know why he had that blend. So many things wrong with it.

 

[stuartv]

The colloquial use of standard gas is the correct gas among standard gasses for that dive, no? Whether you like WKPP, GUE, or the others (UTD, etc), none would suggest 32% for Eric’s dive.

And “best mix” per diver on a project like this would be extraordinarily asinine.

None of what you said changes the fact that no, using standard gases would not insulate you from what happened. There is NO gas choice methodology that would have lead to a choice of using the gas he used on the dive he intended to do.

He did the dive using a gas that he (I believe) knew was not the right choice for that dive. Once a diver makes a conscious decision to use a gas that he knows to be not the right (or even a good) choice for the dive, how would a different methodology for choosing his gas insulate him from the risk? He CHOSE to take the risk of knowingly diving a (very) suboptimal gas.

If you're going to say that using standard gases automatically implies choosing the correct gas for the dive, well, then so does any other extant, accepted method of deciding on gases. Standard gases have no advantage there. Implying that "best mix" does not take into account ANY other factor other than the planned max depth for a specific dive is well, I feel like it is disingenuous, at best. Or maybe naïve, if that's REALLY what you think it means to choose the best mix for a dive? As I was taught, best mix for a dive does include calculating an FO2 and FHe, but those are the just starting numbers. They are not set in stone. Every other aspect of the dive can influence the final numbers chosen - including team logistics, contingencies, and other things.

 

[tursiops]

"Best Mix" in a limited sense means an FO2 that allows the max depth of the dive with minimal N2; it is primarily a Nitrox concept. In a greater sense, "best mix" ought to mean for any dive, Trimix or whatever, but then you have to take into account narcosis, gas density, team gases, SOPs, etc. This poor guy was not using "best mix" in even the limited sense, much less the greater sense.

 

[stuartv]

"Best Mix" in a limited sense means an FO2 that allows the max depth of the dive with minimal N2; it is primarily a Nitrox concept. In a greater sense, "best mix" ought to mean for any dive, Trimix or whatever, but then you have to take into account narcosis, gas density, team gases, SOPs, etc. This poor guy was not using "best mix" in even the limited sense, much less the greater sense.

Exactly. He wasn't following his training or any kind of team standards. So, if he was going to behave in that way, how would it have made any difference if the team was using "standard gases" versus whatever methodology they was actually using?

Again, I am only making the point that standard gases would NOT insulate anyone from the problem that occurred.

 

[Manatee Diver]

Again, I am only making the point that standard gases would NOT insulate anyone from the problem that occurred.

No it won't. But it does change the mindset behind gas selection. You aren't making trade offs like with a best mix approach, you go down the list until you reach the gas which has a maximum depth below your absolute max depth.

So there is less chance for someone to consider "Perhaps I don't need helium that much."

No system is perfect, but I think that between this accident and the incident with Gus, I am hoping that they've taken a step back to think about ways to make their SOP more fail safe.

 

[Hiszpan]

… I am hoping that they've taken a step back to think about ways to make their SOP more fail safe.

But is it a domain of SOPs to have the team members not compromising safety of other team members by diving a maverick, by any standard, gas selection? Or is it rather an axiom that is always operating in any dive setting, like, for example, don’t dive without fins on your feet?

 

[lermontov]

But is it a domain of SOPs to have the team members not compromising safety of other team members by diving a maverick, by any standard, gas selection? Or is it rather an axiom that is always operating in any dive setting, like, for example, don’t dive without fins on your feet?

yes- in the context of an exclusive group that has applied and obtained permits to undertake the dive i would have thought there would have been every consideration to ensure a safety protocol -one that included agreed upon gas mixes instead of individuals doing other own thing - once you step out of the 5 mates in a boat arena and start dealing with government departments i would expect a much more rigorous systems approach to maintain the integrity of the expedition and its name ie KISS and the primary stake holder ie the department who issued the permit

In our own group of divers we would step in and speak up ( and have) if we saw someone doing something that put themselves and others at risk

 

[Manatee Diver]

But is it a domain of SOPs to have the team members not compromising safety of other team members by diving a maverick, by any standard, gas selection? Or is it rather an axiom that is always operating in any dive setting, like, for example, don’t dive without fins on your feet?

No system is fool proof and someone actively working to sabotage the system can probably find holes to exploit. But you can make it harder with the right SOPs, and good team selection to weed out the mavericks.

 

[John the Pom]

I'm still trying to think of all the possible reasons he could have died except oxtoxing.
At 165feet his ppo2 should be around 1.4-1.5 even with more o2 getting pumped in the loop, the highest reported ppo2 of 1.8 is still nowhere close to immediate oxtox symptoms (the Yugoslav navy manual claimed those are expected at 2.5 or higher ppo2, and they actually tested that in dry chambers and working dives)
I personally know a lot of divers who were under very high work loads at higher ppo2, including me.

My ex-Navy diver buddy was tested in a chamber for high PP02 tolerance but, following a short illness, he had an oxygen seizure at a fairly low PP02 and had to give up his career as a Navy diver. My understanding is that PP02 tolerance can be affected by a number of factors.