Narcosis

[supergaijin]

Describing what narcosis feels like is like trying to describe what a banana tastes like. What does LSD feel like? Alcohol? Weed? A coffee buzz? Endorphins from exercise? The individual sensation differs so much, that it's pretty much impossible to give an accurate description.

From the Commandant himself:
“I am personally quite receptive to nitrogen rapture. I like it and fear it like doom. It destroys instincts of life. Tough individuals are not overcome as soon as neurasthenic persons like me, but they have difficulty extricating themselves. Intellectuals get drunk early and suffer acute attacks on all the senses, which demand hard fighting to overcome”…

I never used to feel narcosis until I learned more about diving in general. Diving the same dive sites and depths became routine. I was still enjoying myself but was more free to explore more of myself and that was when I started noticing narcosis especially around the 25m mark. My first symptom is tunnel-vision. I can definitely see my field of vision becoming narrower- the peripheries are darker.

So when will you feel narcosis? I would suggest that like me, the feeling is there already but you haven't become aware of it. Sounds a bit like 'Confucious says...' but ya know: Even a stopped clock is right twice a day.

EDIT: I remember one dive in the Philippines to around the 35m mark with a guy using a camera. Talking about the dive afterwards I was getting some blank looks from him, so I showed him the photos he had been taking. His buoyancy and diving skills were fine but for him, the memory of actually taking the photos was lost in the fog. His face was priceless.

Another time, another group we descended to around 20m. Sorting ourselves out, we started to swim a bit and looking back I saw that one diver hadn't moved. I swam back, signalled and she signalled back OK? OK etc. but still didn't move. Puzzled, I took her by the tank valve and started the dive, ascended a bit and then understood that she was narced at that (fairly shallow) depth. Later I realised that I recognised the symptoms of narcosis in another diver only when I myself was in shallower water. A double whammy.

I want a banana.

 

[TSandM]

I had a set of interesting experiences in the Red Sea. We were diving a wreck called the Numibia. The wreck lies bow up and stern at the bottom of an almost vertical reef. The wreckage begins at about 70 feet or so and goes down to 200.

The first dive I did on the wreck was on 32%. We went down to about 100 feet, because we were looking for a hammerhead shark who had been lurking near there. I thought the wreck was very boring because there was no color on it -- it was all grey, and the coral was drab.

The second dive I did on 21/35. We went deeper than I'm willing to admit, and I was amazed at the wreck, because it was COVERED with soft corals and sponges and little patches of green stuff that looked like moss. There were gorgeous, flamboyant lionfish and lots of small fish in the holds and dark spaces.

The third dive was on 32%, and the wreck was back to being gray.

BTW, I did the wreck the following year on 21/35 but didn't go nearly as deep, and the wreck was still beautifully colorful at the 100 foot range -- so it wasn't that the shallow part was dull. It was my BRAIN that had gone drab.

 

[buddhasummer]

Nitrogen narcosis has the potential to turn a simple problem into a catastrophe for all divers, often even more so for a new, inexperienced diver where even the simplest of task loading can cause a major problem.

Diving to 170ft was more than a little risky but I guess you don't know what you don't know...although your training instructor should have discussed the dangers of NN and diving beyond your limits. The "Tech" instructor who took you to 170 was irresponsible.

I understand what you say about the benefit of experience but the ocean is not the place to "try" things out for the experience especially when unaware (?) of the possible risks. Gaining knowledge sitting at home reading, learning is unlikely to kill you but it may save you.

I have suffered NN a couple of times that I can remember, once I missed a shark while chasing another divers bubbles, it was pleasant and another began to feel an impending sense of doom, it was quite unpleasant. If I had had any sort of issue on either of those dives I question whether I could have dealt with it appropriately. From memory both dives were around the 30 meter mark. Point is both times the effects were different in fact polar opposite.

At 170ft (52meters) if something goes wrong the margin for error is very slim, for an inexperienced recreational diver on air it's likely nil.

We often don't know how we will react to a given situation until it happens. Diving depths beyond skill, appropriate training/equipment/experience etc is not the time to learn that you have a panic response or that NN sends you into a panic state and/or reduces your problem solving abilities.

Sorry for the rant but 170 ft for a newish recreational (?) diver is a little concerning.

Safe diving.

 

[ianr33]

On my last dive trip I was fortunate enough to have an instructor willing to take me to 150 and 170 on different days.

Single tank?

 

[mac.calder]

We wanted to explore narcosis a little bit more so my buddy and I came up with a little test - we went on a dive to 30m with a sandy bottom on a nice warm day with minimal current and good vis, made ourselves negative and knelt on the bottom. On my wet-notes we had pre-written 4 sets of 10 maths problems - stuff you learn in primary school - some long division, adding 3 eight digit numbers etc - all sets were of a similar difficulty. My buddies job (to keep task loading minimal) was to watch my air, watch his air, time me completing the problems and watch our bottom times. My job was to complete the first set.

Completed in 2:52. We then finished the dive. During our surface interval I completed the second set - in 1:47. Next dive was to 22m. I did the 3rd set - 2:08 and the last dive of the day was to 10m - 1:56. We repeated the same test with my buddy another day and found similar results (They are not in my log book)

It is by no means a large enough sample group to PROOVE that we were narked - we certainly never felt it, but the times paint an interesting picture.

 

[nimoh]

I had a set of interesting experiences in the Red Sea. We were diving a wreck called the Numibia. The wreck lies bow up and stern at the bottom of an almost vertical reef. The wreckage begins at about 70 feet or so and goes down to 200.

The first dive I did on the wreck was on 32%. We went down to about 100 feet, because we were looking for a hammerhead shark who had been lurking near there. I thought the wreck was very boring because there was no color on it -- it was all grey, and the coral was drab.

The second dive I did on 21/35. We went deeper than I'm willing to admit, and I was amazed at the wreck, because it was COVERED with soft corals and sponges and little patches of green stuff that looked like moss. There were gorgeous, flamboyant lionfish and lots of small fish in the holds and dark spaces.

The third dive was on 32%, and the wreck was back to being gray.

BTW, I did the wreck the following year on 21/35 but didn't go nearly as deep, and the wreck was still beautifully colorful at the 100 foot range -- so it wasn't that the shallow part was dull. It was my BRAIN that had gone drab.

now if you could only narc a camera to capture those colors

 

[jewelofnile69]

Wow! I learned a LOT from this thread so even though I feel that the reason for the start of this thread is a little crazy, I'm glad it was started. I'm a relatively new diver. I have about 30 dives under my belt and am only OW certified (although I'm taking AOW and nitrox in August). Anyway, I have not felt the effects of narcosis but I wanted to share a story with you since I think it is fitting and shows why we all need to be responsible divers.

We were in Bonaire back in early 2011. There were 5 of us. One that was with us was all of our dive instructor (who just happens to be my husbands photography partner and best friend). Andy has been certified since he was 14 (he's now about 42) and has hundreds of dives under his belt and every cert you can think of. Anyway, with this group of 5 I was the newest diver with the least number of dives under my belt and so even though my husband was with us, Andy was essentially my dive partner. We were getting 2 to 3 dives in a day with our deepest dive always (obviously) first in the day. But the deepest I had been at was about 70 feet (but generally 60-65 feet). Later in the week when I had about 8 - 10 more dives under my belt, we decided to dive the Hilma Hooker. For those that have been to Bonaire, you know that the bow of the boat is around 60 feet (if memory serves me correctly) and the stern around 90-100 ft. Andy now had good faith in my diving skills so he decided to bring along his camera as he had some contracted shooting to do for Diver magazine and Bonaire Nights. I was still going to stay around Andy as he shot but as we were on our way out, something went wrong with the camera (he had a new fish eye lens on) and he, my husband and I surfaced (the other 2...his wife and another buddy....kept going). Turns out his camera FLOODED! (Good news, it was repairable but that wasn't found out till back in the states and we still had like 2 more days of diving.) Anyway, so he told DH and I to go on. Well, my husband and I met up with the other two who essentially waited for us at the bow of the boat and then we all explored the Hooker and I did hit 100 feet. We were watching our dive computers and never once exceeded our limits (although as only basic certified I technically was exceeding my certification) and we then surfaced slowly with safety stop as always and thought everything was fine. When we got back up, all 4 of us were telling Andy about our dive. HE WAS PISSED! First, he figured out we must have been narc'd because none of us could remember much of the stern of the boat (we were all diving air) and even though we didn't exceed our limits, we were close when we scanned our computers. We all learned a BIG lesson that day. I think he was mostly mad that the other 3 (all who have lots more dives than me) took me that deep. I also do remember feeling a little paranoid as we got deeper (maybe around 80ft or so) but can't recall exactly.

I want to thank you all for sharing your stories as this is helping me learn a lot.

 

[Jared0425]

Narcosis is a constant change for most people. Those of us that still dive deep air will tell you that. One day you feel fine and alert while the next you are buzzed, anxious, relaxed, scared, etc. Depends on the conditions and health also. Diving to 185 here in the lakes is different than 185 in the ocean. Also your hydration, sleep, food, and physical health depends. Narcosis can be easily handled if you have the correct thought process and scuba "instincts" and skills. Now a days it's just easier to use helium which reduces the effects. Either way, that instructor was walking a fine line.
Jared

 

[gcbryan]

I think that the biggest reason that nitrogen narcosis affects the same person differently on different days is its effect as a catalyst. If you are anxious for whatever reason and then add nitrogen narcosis you do remember its effects.

In many cases the anxiety is CO2 induced. Nitrogen narcosis and fighting a current or doing something difficult and new combines with anxiety and potentially anxiety triggered by CO2.

Without that other component you may not notice it but the effect is a little like being a little ( or a lot) duller mentally than you would normally be. Kind of like just waking up and not quite having it all together yet. Nothing is obviously wrong it just takes you a few more seconds to figure out how to do something easy and mundane. It's like losing a few IQ points.

I like the analogy that someone mentioned above of having so very few drinks that you don't feel the effects at all until you stand up and try to dance and make a fool out of yourself

If you went to 170 fsw and didn't feel anything I'm sure you would feel something if you now went back there and had to fight a current before getting to the point where you could come up (having to make it back to an anchor line or whatever).

Other than the low number of dives and trusting an instructor that you didn't (presumably) know I don't have quite the problem with your line of thinking that many of the others here who have posted do.

I like to experience (some) things myself under more controlled circumstances that I could possibly have to face later when the circumstances are less controlled. This is not a blanket statement I'm making however (just to ward off the "would you jump off a roof just to see what that was like? comments).

If you knew the instructor and he/she knew you and how you both reacted when stressed and if the equipment issues had be considered I don't have an issue with the logic of what you did. However going to 170 fsw without either of you knowing all that much about the other (and yourself potentially) would be my objection (and the limited dive experience that you had).

 

[faze]

Met an Instructor once that advised me he often gets narked below 35m if he's heavily hung over - so that may work, wouldn't know because I've never dived with him (and never will!!!!!!!!).

You're local chamber may well run sessions specifically designed to allow divers to experience narcosis.