Nitrogen Narcosis and me

“I never get narced”, Pronounced ‘narked’, you hear this all the time from new and veteran divers. “It just doesn’t seem to affect me.” Yeah, right. 

Nitrogen Narcosis, or sometimes referred to as Rapture of the Deep (credit; Jacques Cousteau?) is simply the feeling you get breathing large percentages of Nitrogen while you are subjected to outside pressure. Getting the Nitrogen is no problem as the air we breathe is almost 80% of this somewhat inert gas. The pressure, for most, usually comes from Scuba Diving, hence “the Deep” bit.


I am not a Doctor; I just don’t have the patients. (Sorry), and I must admit that I do not really have any formal education in the subject we are about to delve into, but that has never stopped me before, and in the end you and I will at least know my opinion.

This feeling you get from Nitrogen Narcosis is usually subtle and can be quite pleasant. Somewhat along the lines of the gas the Dentist might administer to ease the discomfort of the drill, but much less, at the beginning. As narcosis is product of pressure, the deeper you go the more intense the effects. It is generally accepted that this phenomenon starts to occur at about 100 feet deep, as this is where it is perceived by most divers. At this depth it is often described in the terms of the Martini Effect where here the feeling may remind you of the effects of a martini, or two. It can be a feeling of contentment, mild euphoria, and giddiness which for some is desirable, and there are those who will “just go down to catch a buzz”.

We have to remember that we are describing a “feeling” or probably more accurately, a level of impairment, and that like alcohol or drugs the effect may vary widely among individuals. Yet there is no getting around the fact that for everyone the effects will intensify the deeper you go (physics and physiology stuff, I refer you to the disclaimer). It has been my personal experience that the environment also plays a part. For me personally, places with overhead covering like swim-throughs, and the darker places we may choose to dive seem to ramp up the effects.

My first experience with narcosis came right here on Roatan years ago. I was on my first warm-water dive vacation, escaping the cooler climes of diving around the Seattle area, to Cocoview Resort. On the trip were my Scuba Instructor Nikki and mutual friend Master Scuba Instructor John. During one of the off-gas B S sessions the subject of narcosis came up with John relating an experience at a hard-hat diving school where he was taken to 175’ “deep” in a decompression chamber with a half a dozen other people, and the uncontrollable laughter that ensued. Well, this sounds like my kinda party, so after mentioning my willingness to try this experience, John made arrangements for Nikki and I to accompany him to a depth of 150’ to give this stuff a taste.

One planned thing led to another and the next day finds the three of us descending past the recommended diving depth of 130’ and on our way to our goal, a flat coral strewn valley adjacent the reef wall at 150’. It is very surreal, with the tropical light being filtered through so much salt water it is much like dusk on the surface, and it is a cozy feeling like dimmed lights in a soft living room. Nikki, my dive instructor, who is a rock solid diver and very calm, slow and at ease in the water, now seems far more animated than normal, swimming around looking in crevices with an unfamiliar hurried attitude. Shortly she is waving John and me over to see a nudibranch (her thing) that she has found. I have to admit it was pretty cool. It was the color of bottle of Dawn Dishwashing Soap (original) held up to the light, an unearthly iridescent royal blue.

Time to go, you just can’t stay at 150’ for long, and on the surface I start marveling at the color of the nudibranch that Nikki found. John is looking at Nikki like “he’s doing it again”, and Nikki turns to me and says, “It was white.”


“Yes”, John says, “white”.

That was 15 years ago, and it still bothers me.

For me personally, narcosis also has a far darker and more ominus side. During deep training dives in the Puget Sound I found that the effects were more pronounced, perhaps because of the darkness, and that they ramped up much faster as you went deeper. The pleasantness of “the Buzz” was almost instantly replaced by anxiety, and in a few more feet, fear. Fear of what? I haven’t got a clue, but no amount of gauge checking, and OK-ing to buddies would relieve the feeling.

A few more feet, terror. You know the feeling; you go through a door and your butt-head friend jumps out from behind something and scares the willies outta you,  but you don’t get the relief of seeing your buddy’s gloating face, it just keeps increasing. Heart rate goes up, breath rate increases, and I am approaching the “P” word. That’s the bottom for me, and this                                                                                       dive is over.

Going up just as little as 10 feet can bring almost instant relief, and in 20 or 30 feet the sun starts to shine, and the birds are singing…….


For me; been there done that, got the t-shirt, and no reason to go back.

However, a little nitrogen narcosis in moderation is still quite pleasant, but be sure to have a designated diver.