Narc vs dark narc?

[Stoo]

Nitrogen narcosis is the resulting physiological condition of nitrogen under pressure having an anesthetic effect on the diver and altering the state of consciousness. It has nothing to do with ambient lighting.

From a purely physiological perspective, this is accurate. I think most will agree however, that the degree of narcosis and the effect of the narcosis is effected by many things, and I would include visibility and "ambient light" in that, so I will respectfully disagree with you.

I suppose one could make the same comparison with alcohol here as well. A guy can drink six beers in a given time and be "fine" one day and on another occasion, he has a "buzz" going. In either case, his blood alcohol is going to be about the same, but he can feel very different for reasons that are probably not entirely clear.

 

[Dr. Lecter]

I know which one is less pleasant, but I'm not sure which is really "worse"... When happily buzzed I'm likely to continue on my merry way, and may be getting into actual danger without "caring" enough about it; with a dark nark my immediate instinct is self-preservation and an ascent away from the feeling of "imaginary danger".

Ding ding ding. I do much better at 220' on air in the dark guts of a wreck in bracing cold water, or far enough down here in HI that the light really starts to go on what some here would call a lean trimix blend, than I do just lazing about in crystal clear, sunny open water at depths between 130' and 200' on air.

The risk in the former situations is crossing the line from a focus/presence-assisting sense of exactly where you are and what you're doing into an uncontrollable panic to GET OUT that's inconsistent with the physics and physiology of your situation. The latter presents an opportunity to mindlessly wander into a deco obligation you never intended to incur, an OOG situation, or any number of other things.

 

[victorzamora]

From a purely physiological perspective, this is accurate. I think most will agree however, that the degree of narcosis and the effect of the narcosis is effected by many things, and I would include visibility and "ambient light" in that, so I will respectfully disagree with you.

There's a cave I dive frequently in the 90ft range with zero narc problems. I did the dive once with my backup light only (well, one of my 5 backups) and I was narc'd beyond all belief. That's common. I feel like the added light helps stabilize me, it helps me fight off the disorientation. I feel slightly slowed in the 110ft range, but no signs of "true narc" when it's clear and bright. I was in Roatan doing my AOW and at 110ft I outpaced most of the other students in the "mental acuity" skills test......when they were dry. But when the vis gets reduced, that nitrogen gets a MUCH tighter hold of me.

As for which one is more dangerous, I think it's a toss-up. With Dark Narc you've got the extra awareness which is good, I guess......but sometimes it gets pretty crippling on me. Happy narc is dangerous if you're not aware of it. I keep an eye out for it, and I'm usually pretty good to go. So, I'd say Dark Narc is dangerous if you're really vigilant regarding narcosis.