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CaribbeanDiver
12-25-2007, 22:03
Recently, I was involved in a conversation about deep diving. This conversation included the increased pressure, decreased bottom times, and the added risk of narcosis. (and what narcosis is)
The other person was not a diver and most of this was new to her; although, I am certain she was naturally aware that pressured increased with depth.
Then she asked a very good question. This never occurred to me and I bet it doesnt occur to others in the same situation. That is, as I explained the requisites of the AOW course, one of the dives was a deep dive and the purpose was to possibly experience narcosis along.
She asked, well, who is with you and I stated, "the insturctor". To which her reply was, well can this narcosis effect anyone? And if so, what happens if the instructor becomes narc'd? Then even worse, what happens if you and the instructor both become narc'd?
Mmmm, interesting scenario. Never occurred to me, I didnt experience any narcosis during my 127 fsw dive but I know that I can the next time I hit 80 fsw or deeper. I also felt extremely confident that my instructor would help me during that 127 fsw dive if I needed help. But if he became narc'd......
After her question, I had to pause and think,,,,mmmm.

NitroWill
12-25-2007, 22:05
Well, that is the whole point of the class - to give you supervised training with someone who should be experienced in the subject. That is why it is important to make your first sets of deep dives (and other new type of dives, for that matter) with someone who is experienced with them so they know how to prepare, train, act, and react to the circumstances - so you can be prepared and make a safe dive and learn!

Grin
12-26-2007, 09:38
I am sure someone else can explain Narcosis better but here is my attempt.
Narcosis is the result of breathing compessed gas containing Nitrogen (I think). The deeper you go, the more the Narcosis effect becomes. The concern with Nitrogen when talking about NARCOSIS is not related to tissue loading or the bends or anything in that direction. The discussion about Narcosis is the immediate/present effect of decision making as depth increases the Narcosis effect increases. There is a barely noticable narcosis effect in depths as shallow as 60-80ft. At depths over recreational depths(130ft) it really becomes a concern though. It is somewhat of a drunken state that increases immediatly as you go deeper, and it decreases just as fast as you accend. So at depths over say 150ft it can be a major effect. There are people who dive air to well over 200 ft believe it or not. The fix is to use breathing gas, such as, Helium. The other thing to consider is everyone is different. Some may not experience (or claim not to expeirience) Narcosis at relatively normal depths of 70-120 ft or so. Personally I know what Narcosis is. To me I think it is the effect of making dumb decisions at depth and then surfacing and wondering why you did it. Like when your down there and not wanting to come up. You know your suppossed to start to surface at around 1000lbs of pressure, but you push it right to the limit. Maybe staying down, a few extra minutes, and then have to come up on 500lbs or ?? When your up top you might never consider doing something like that, but down there your Narcosis dumb and don't even know it.
If you have ever encountered sharks underwater this is a great example. Up top the thought of sharks is frightening, but down deep(to me) I am in zero fear of them. That's Narcosis!
It has been described that some people can be in such a Narcosis state that they are almost frozen and staring into space. If their regulator second stage failed they would do nothing to regain control etc... Even with a spare second stage right there, they would do nothing. That's extreme Narcosis! That would be pretty rare at recreational depths.
When you get home, and your going over your day in your mind, and you wonder why you pushed a limit when you knew better, or why you didn't think of something during your dive, etc... That is probably Narcosis! Many will say they have no Narcosis effects, but their actions may tell a different story. I don't think it is anything you really feel. It is your decision making ability at depth that explains it. You can't really judge that while down deep. But you can be aware.

No Misses
12-26-2007, 09:46
I am sure that I will get some grief from this response. But, here it goes anyway J

Narcosis is like alcohol inebriation. Some of the old diving books even refer to the “martini effect”. The basic assumption is that for every 33 feet that you descend, the narcotic effect is like drinking one martini. To follow this line of thinking a little further, I am sure that we all know a person who is stumbling after one drink or the opposite – a person that is still coherent after consuming large amounts. The trick is to acknowledge that you are impaired and to temper your decisions based on this fact.

Good Luck and happy diving J

fisheater
12-26-2007, 23:27
Every been administered nitrious oxide at the dentist's?

THAT'S narcosis.

scubasavvy
12-26-2007, 23:58
I am sure that I will get some grief from this response. But, here it goes anyway J

Narcosis is like alcohol inebriation. Some of the old diving books even refer to the “martini effect”. The basic assumption is that for every 33 feet that you descend, the narcotic effect is like drinking one martini. To follow this line of thinking a little further, I am sure that we all know a person who is stumbling after one drink or the opposite – a person that is still coherent after consuming large amounts. The trick is to acknowledge that you are impaired and to temper your decisions based on this fact.

Good Luck and happy diving J

Actually, sounds about right. Too bad I can't hold my liquor :smiley2:.