Extreme hypoxia! That is what I was looking for thank you!Extreme hypoxia. Ox tox is breathing too rich of an 02 mix. This was the opposite as the O2 content was zero.
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Extreme hypoxia! That is what I was looking for thank you!Extreme hypoxia. Ox tox is breathing too rich of an 02 mix. This was the opposite as the O2 content was zero.
Racking up minutes and exposure on a LOB is IMHO no place to be deciding to push limits even further....
You might also be looking for anoxia, or total lack of oxygen.Extreme hypoxia! That is what I was looking for thank you!
It depends on how long you stayed down there and how active you were!Here are my questions:
Just how dangerous were my dives?
Of course there are some safety margins. What tourist industry could tolerate e.g. 1% dead clientele?Was I taking a huge risk or are there already safety margins built in?
Can you supply some sort of an official estimate on this for NDL diving?
I know of many cases with technical diving, but I don't believe I have ever heard of a single one in NDL diving. I would like to see some examples the "way too many people" if you can find them.
In the technical diving cases I know, we are not talking about someone going to a PPO2 of 1.55 for 4-6 minutes. We are talking serious MOD violations, often caused by the diver thinking he or she had a different mix than reality. In those cases, the toxicity came after significant time. Here are some cases I know of. I am writing these from memory, and some of the details may be a tad--but only a tad--off.
- A diver broke his foot and could not dive for several months. When he was ready to dive again, he took his double tanks to a wreck (Hydro Atlantic) with a deck at 150 feet/45 meters and about 170 feet/52 meters to sand. He did not check the tanks because he was sure they had air, but they had 36%. His buddy told me it took about 20 minutes before he toxed.
- A cave diver used a tank that was clearly marked as having pure oxygen for a dive to 100 feet. He told his friends he had filled it himself, so he knew it had air instead of oxygen. He refused to test it. I am not sure how long he was diving on pure oxygen at 100 feet before he toxed.
- A cave diver was supposed to leave a decompression bottle with 50% at a 70 foot staging area and take a different one more appropriate for 200 feet. He left the deep bottle at the staging area and took the 50% to 200 feet. I don't know how long he was diving at 200 feet on 50% before he toxed.
I have only been an avid ScubaBoard participant since 2004. I don't recall any during that period. Perhaps you could link to one.There have certainly been a few other stories discussed on ScubaBoard, though.
That would be very surprising. Can you find a direct quotation?I only did the SDI Nitrox class in 2017 and my recollection is that the book primarily focused on 1.6 being the limit with 1.4 for those wanting to be more conservative.
It's been years since I read the book. I don't recall anything like that, but my memory is far from perfect. Perhaps you could find a quote on that for me? (I could try to contact Bernie to see if he remembers writing about it, but I really don't want to bother him.)The book "The Last Dive" I believe mentioned someone that routinely took 39-40% deeper than 130 feet, but eventually had a convulsion and died. (Just my recollection.)
Be specific.I did SDI nitrox earlier this year and the written materials still say 1.6 is the limit.