kotik
Contributor
I didn't though... as sometimes happens on the internet, I plowed on ahead with saying what was on my mindYou could have stopped at that.
Here's what I'll say for myself, not speaking on anyone else's behalf:
- Here's an essay from Shearwater on the subject. It cites an Israeli study that logged probable CNS toxicity occurrences at PO2 ~1.6. Shearwater's article is geared toward warning about CO2 buildup for rebreather divers, but CO2 buildup can have other sources too. Anyway, low probability or not, it does look like there's documentation of O2 toxicity symptoms at PO2's as low as 1.6
- I have 'heard', ancecdotal only, of one or two cases of fatalities in the Florida caves where the best guess on what went down was O2 tox at relatively low PO2.
- Convulsion underwater is almost a certain death sentence. I'm not going to offer any support for that statement. If anyone cares to dispute it I'll put it to them to come up with the list of those who've convulsed and lived to tell about it.
Higher PO2's, I think the possibility becomes more and more real. Somewhere on the spectrum it shifts from becoming a possibility to a statistical certainty that someone among the many divers out there will tox and die. There is no good reason to introduce that extra risk and I don't think it's responsible to encourage whoever in the world might be reading this thread that the risk of high PO2 is really overblown.