My first deep dive

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RyanT

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@wedivebc, CO2 is actually 25x more lipid soluble than nitrogen. Solubility doesn't tell the whole narcosis story though. The physiological effects of CO2 impart an even higher narcotic effect than the 25X solubility factor.

 

tbone1004

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Where did you get that statistic from?
the 25x solubility factor is what I was thinking of, but I dug back and the initial research that was published in the 70's indicated it has 20x the narcotic potency of N2, with O2 being 1.7x and He 0.045.
Whether it's 20x or 25x or even 15x, the point of it was to emphasize how important CO2 management is on a dive and how rapidly it affects your body compared to how long it takes to clear.

If you ask most people that say they've been narc'd at reasonable depths, say 80-120ft, odds are they were doing some sort of work, often kicking against a current. It's not nitrogen narcosis causing that...
 

wedivebc

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the 25x solubility factor is what I was thinking of, but I dug back and the initial research that was published in the 70's indicated it has 20x the narcotic potency of N2, with O2 being 1.7x and He 0.045.
Whether it's 20x or 25x or even 15x, the point of it was to emphasize how important CO2 management is on a dive and how rapidly it affects your body compared to how long it takes to clear.

If you ask most people that say they've been narc'd at reasonable depths, say 80-120ft, odds are they were doing some sort of work, often kicking against a current. It's not nitrogen narcosis causing that...
Could you please cite your source? I have seen very little data quantifying the narcotic effect of gases. I have seen carparisons of solubilility of gases in lipid tissues and references to the Meyer-Overton theory but I have seen no scholarly articles defining oxygen impairment. This matter is still under much debate.
 

wedivebc

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@wedivebc, CO2 is actually 25x more lipid soluble than nitrogen. Solubility doesn't tell the whole narcosis story though. The physiological effects of CO2 impart an even higher narcotic effect than the 25X solubility factor.

thanks, I will dive into the reference list and that should lead me to my answers
 

Bob DBF

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Any mild narc on my part, if that's what it was, seemed to mostly retreat and stay at bay once I realized we had a "mission".

So she went to 150' to get to him, and I went to 147' to stay close in case needed. She got no reaction at all from him, and took his arm as we all ascended, and and at about 100', he "woke up" and became functional, so she let him go at that point, he was looking and acting "normal" he adjusted his BC on his own and was okay thereafter.

One of the effects of narcosis is to narrow your focus, did you check your air to insure you had enough to make a rescue, if the answer is no, you were narked, and if you were at the end of your dive it could have gotten quite ugly and led to three casualties.

I've never felt narced once. Max depth 137 ft twice, many more dives 100 - 127

One rarely feels naked when they are. It just impares you without notice, if and when there is a problem one may not have the mental acuity to resolve it. As long as everything goes well, divers assume they were not narked, and they are very wrong.
 

nolatom

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One of the effects of narcosis is to narrow your focus, did you check your air to insure you had enough to make a rescue, if the answer is no, you were narked, and if you were at the end of your dive it could have gotten quite ugly and led to three casualties.



One rarely feels naked when they are. It just impares you without notice, if and when there is a problem one may not have the mental acuity to resolve it. As long as everything goes well, divers assume they were not narked, and they are very wrong.
It strains my memory but I do believe I checked air (probably N-28) at the same time I finally looked at my depth gauge, just after levelling off. Don't recall exact number but would have been around 2500 since it was very early in the dive and had been a quick descent. Noticing the "statue" diver needing help came right after we had finished descending. And the trip over and deeper didn't take long. And afterward, we did a "normal" remainder of the dive up at around 80' where we were supposed to have been to start with.

And yes, had this all happened later in the dive, I can picture getting more narced and losing track of time and depth to where the rescuers would also become rescuees. I had already made a couple of mistakes. Happening early as it did, I got away with it.

And fortunately I had a buddy with long experience and a cool head, who had been a DM on occasion with several of the Jupiter boats.
 

RobPNW

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Luckily I have never felt anything at depth. With that said, I usually do intense breathing control because I don't want to plow through my gas fast at depth. Can't say whether that was the difference but it can't hurt.
 
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