Nitrogen narcosis

[Storker]

Has something like this every happened to anyone else on here?

I've been just fine at 35m (or at least, I've thought so), and I've been noticeably narked around 30m, so bad that I chose to ascend.

It all depends. But the nark is insidious. Don't trust yourself around or deeper than 30m.

 

[shurite7]

Nitrogen Narcosis can be weird, highly inconsistent, and a real eye opener.

This is very true. Over the years of guiding divers, there is a behavior that I have noticed with some men and women that are obviously narced. I usually swim up to the diver and point to their computer so that they look at it. Some guys look at it and suddenly rocket to a shallower depth and then stop; women on the other hand have given me the ok sign, after they look at their computer, then continue to descend to a deeper depth as if they were in happy land. I can’t say this is normal behavior of either sex, yet it is interesting that I have witnessed it enough times to be aware of it. I’ve had to slow a couple of guys down and get them to relax, and couple of ladies I’ve simply grabbed their tank valve and gently pulled them up. In each case the people looked at me, gave the ok sign, and continued the dive as if nothing happened.

 

[Kay Dee]

I've been just fine at 35m (or at least, I've thought so), and I've been noticeably narked around 30m, so bad that I chose to ascend.

It all depends. But the nark is insidious. Don't trust yourself around or deeper than 30m.

With all due respect that is not entirely correct. Obviosly as a new / newish diver you are almost certainly going to be effected by narcosis at 30m and deeper iniitialy when you venture there. Although not suggesting you do so, the more times you go there the more you will become aware of its insidious effect - or not as the case may be - and then choose whether you want to keep doing that - on air - or switch to a better breathing mixture for those deeper dives.

But before the days of mixed gas there were a lot of folks diving much deeper on air and getting things done. Before developing the "lust for rust" myself I did my many many hundreds of dives on the Great Barrier Reef and almost all the outer islands in the Coral Sea (it helped to have a friend who owned a liveaboard that did the GBR anf those outer islands) and those consisted of DEEP vertical walls. So I will be first to admit that as a relitively new diver with less than a 100 dives when I first went out there I felt the first noticable effects of narcoss at abot 35m, and noticed a distinct change in 'taste' in my mouth at around 40m; what we reffered to as "the hospital taste". Slowly over the many trips, and given you were out there for ten days to two weeks with up to four dives a day, the opportunuty arose on a consecitive day bases to slowly work my way way deeper, but giving the dramtically shrinking NDL's 'down there', never spent very long 'down there'. But long enogh to notice the changes and awareness of them and my suroundings and complete the tasks at hand (as I was already taking u/w photos). Years later when my interests had shifted to the wrecks off Gudalcanal (Solomon Islands), and before helium was available there, we were doing 60-65m dives with 30 odd minutes of bottom time and taking photos or video to boot then also. And even when helium became available (we had to freight it in ourselves at first) we still used air, or somtimes a topped up a left over mixed gas mix if we had the luxury of that. Of course once CCR's came along then goodbye to deep air diving, save for the odd liveaborad trips in Asia when again helium was not onboard and it was back to OC doing 60 odd meter wreck dives on air.

Would I choose to do so if I had a choice, certainly not, it would be mixed gas every time, but I would have never foregone a 60m dive because I did not have gas.

So I think its only natural that people feel the effects of narcosis at tne depths you mention, especially having not been down there all that oftan. For me it was the regularity of doing that that 'conditioned' me - for want of a better word - to the effects of narcossis. But as someone else mentioned above about a technical instructor friend getting narced 'shallow', I am not ashamed to say the worst narcosis incedent I ever had was being underweighted in a drysuit at only 30m, on a cold, well very cold 2c on the wreck, very dark air dive in the Baltic Sea.

 

[leadduck]

Obviosly as a new / newish diver you are almost certainly going to be effected by narcosis at 30m and deeper iniitialy when you venture there. Although not suggesting you do so, the more times you go there the more you will become aware of its insidious effect - or not as the case may be - and then choose whether you want to keep doing that - on air - or switch to a better breathing mixture for those deeper dives.
(...)
For me it was the regularity of doing that that 'conditioned' me - for want of a better word - to the effects of narcossis.
(...)
I am not ashamed to say the worst narcosis incedent I ever had was being underweighted in a drysuit at only 30m, on a cold, well very cold 2c on the wreck, very dark air dive in the Baltic Sea.

AFAIK there's still no evidence that you can condition yourself against the effects of narcosis. But there's probably a correlation between nitrogen narcosis and CO2 buildup, and therefore it's not surprising that newish divers tend to suffer more than experienced (=more relaxed) divers. First few dives after a longer pause are also worse and some report that they can go deeper after a few dives, getting used to the environment. Unfortunately some believe their experience gives them kind of a physiological immunity but that's an illusion; they suffer from the same narcosis problem as soon as they encounter a stressful situation and/or other problems such as freezing.

 

[Centrals]

My personal experiences:
1. I need to acclimatize on the first day of a diving trip. No deeper than 30m
2. I have experienced narcosis as shallow as ~24m. Narcosis can strike any time.
3. I could feel the onset of narcosis and act accordingly ie. ascend a few metre to alleviate the symptom.
4. Exertion under water(eg. kicking against current), tiredness(lack of sleep) etc etc could induce narcosis.

Be alert and act promptly.

 

[kablooey]

An almost identical experience occurred to me on a 120 fsw wreck dive off our local coast. We were making a dive at a place and depth I’d done many times before.

On this particular dive, at about 110 fsw, I was feeling fine, but when I looked at my computer it didn’t make any sense to me.

It’s hard to explain. I saw numbers, but I just couldn’t grasp what they were supposed to mean. They were telling me nothing. I stared at the display like it was a Picasso painting... no useful information was getting through to my brain.

I didn’t panic because I knew based on time and depth we were still well within a safe profile. Far from incapacitated, most of my brain seemed to still be working. “So, this is nitrogen narcosis”, I reasoned.
“It’s real!”

Slowly I ascended about fifteen feet, looked at the computer again, and understood the meaning of the numbers perfectly.

This experience has never reoccurred to me this strongly in the fifteen years and hundreds of dives following this event.

Later, during my mix gas training, I experienced normal mental clarity at much deeper depths.

.

 

[Fin Finder]

Divers are a confusing species.
We worry about nitrogen narcosis, plan our dives to avoid it, pay for expensive gasses to eliminate it, watch for signs of it in ourselves and our buddies...

Then when our dives are completed and we’re back on the boat, we hammer beers like Supermen.

 

[BrackaFish]

So yesterday while diving the Lady Luck off of Hillsboro Fl, I got to the depth of 112ft. A good portion of my dives in the past few months have been at depths of 100 to 120ft (about 20 dives)
But yesterday somewhere around 110ft I literally felt like I was having an out of body experience and lost awareness. I caught myself, gathered my thoughts and got my dive buddies attention, accented to about 80ft where the boat was tied off to. Before I went up to 80ft I do remember looking at my dive computer and my NDL time which I was still at 8 minutes. At 80ft I was fine. Fully aware of everything. we continued the dive and everything was okay. But that experience felt crazy. I did tell the dive master and deck hands what happened, they said nitrogen narcosis and that it effects people differently and that I was fine to do the second dive which was a 50ft reef which I was perfectly fine on. Like I said I have a good amount of deep dives logged and nothing like this has ever happened before. Has something like this every happened to anyone else on here?

First, great job on recognizing the issue and taking the correct action. As others have pointed out, narcosis can be a widely variable problem depending on an almost infinite number of different conditions. In the “old days” a good bit of what was taught in Hal Watts Deep Air classes was narcosis “management “. With Trimix becoming more common, this is a much better option although more expensive. As I have gotten older, my go to option is just to stay shallower, at least on most dives. Again, good job one handling this problem. As they say, “ Admitting that the is a problem is half the battle “. Sometimes listening to the post dive talk of other divers makes you wonder how many zombie divers are out there swimming around narc’d Out of their gourds. Be safe

 

[Kay Dee]

AFAIK there's still no evidence that you can condition yourself against the effects of narcosis.

As I said ".........................for want of a better word....".

But if we want to swing on the word 'conditioning', then it would depend entirely on what you call "evidence', IMO, my observation over many years, and that of others. But hey, I am not here flying the flag of deep air diving, just saying is all.

 

[Kay Dee]

In the “old days” a good bit of what was taught in Hal Watts Deep Air classes was narcosis “management “.

The first course I took back in the day (1992 / 1993) in the USA to see if, one I liked deep and dark places and would hence progress into cave diving, and two, just to see how I felt in the blackness of what, IIRC was 240ft or 73m, on air on the bottom.

I did not however think it prudent to continue on to the 300ft / 90m deep air ocean dives with Hal, as that wasn't where I was heading on air, although quite a few did (take that final 'module').