Woman dead, husband injured on 230 meter dive - Greece

[DandyDon]

It is correct. Most trimix classes end at that maximum depth

Okee dokee. Her statement was "the regular certification classes max out at 90m," which itself is wrong, but if she meant "regular trimix classes," then that makes sense.

She started feeling dizzy during their 40m deco stop, kept getting herself entangled in the ascent line, then he became sick too.

I presume that tech dives like this are done with extensive gas testing and any chance of CO contamination is totally ruled out? It certainly wouldn't take much to load up their blood at 230 meters, then rising to 40 meters would start releasing it in overwhelming levels, but surely they have and use adequate testing for that risk?

 

[KevinNM]

I presume that tech dives like this are done with extensive gas testing and any chance of CO contamination is totally ruled out? It certainly wouldn't take much to load up their blood at 230 meters, then rising to 40 meters would start releasing it in overwhelming levels, but surely they have and use adequate testing for that risk?

I don't think that is a safe assumption. I know in the case of deepdoc that highly competent people said that if he was determined to do the dive that he needed his gas prepared by a lab, the margin of error of typical scuba testing equipment is not sufficient for that depth. And no, they didn't do that.

 

[Centrals]

Isobaric inert gas counter diffusion.

"Raising the Death" by P Finch and read how Don Shirley survived the inner ear bend etc etc.
Late John Bennett also suffered the effect on his 308m dive.

 

[RayfromTX]

If they had been successful at this depth, I wonder what their next goal would have been.

 

[Kay Dee]

Huge difference between 110m and 230m.

HUGE, for anyone.

That does not sound right...??

Re 90m / 300ft training depth limit, I can't quote the current agency standards limit, but that figure was the case when I was actively teaching divers, and stayed that way at least for quite some time after I stopped.

So what is the current limit on a course (i.e. given the situation being discussed in this thread, the deepest course) with an instructor present?

As for doing your own (non course) 'training' or work up dives then the skys the limit, or in this case I assume 'the bottom'.

 

[Kay Dee]

I presume that tech dives like this are done with extensive gas testing and any chance of CO contamination is totally ruled out?

Dan, with all due respect, you would be presuming wrong, IMO.

 

[DandyDon]

Dan, with all due respect, you would be presuming wrong, IMO.

Ok, well - it would not take very much CO to poison them at 231 meters, and ascending to 40 meters would release CO bound to their blood at an accelerating rate. With DAN, the agencies, even tech agencies continuing to ignore the risk, I continue to wonder how often it is the undiscovered trigger.

 

[catone]

How would ascending release bound CO at an accelerating rate? Or at any rate? I don't think the CO-hemoglobin bond in itself is affected by ambient pressure (not taking the effect of O2 pressure into consideration here), it's more of a chemical thing. From a total CO load perspective alone, the shallower the better. Or is it not?

 

[RayfromTX]

My understanding is that the effect of the CO is masked by the higher ppo2 at greater depths and is revealed as the lower ppo2 at shallower depths doesn't provide the therapeutic effect that it did when higher. Do I have this wrong?

 

[Dan]

Question to deep divers, inquiry mind wants to know, other than trying to break whatever records (personal, world, Guinness, etc.) and because it is there, what other compelling reasons to go to such cold, dark, unforgiving place? Rob Stewart was trying to film sawfish, but that's only to 70m (230 feet) deep.