Nitrogen Narcosis: What It Is and How It Affects You - Maluku Diving

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

Interesting information in this thread. Being new to scuba and just attaining my OW cert, the topic of depth has come up frequently. I think no more than 60-80ft seems like a good point for starting out. And as I get more comfortable perhaps a little deeper.
 
Nitrogen Narcosis: What It Is and How It Affects You - Maluku Diving
Anybody interested in diving beyond the 60 foot mark needs additional training that includes information on Nitrogen Narcosis. The cause of nitrogen narcosis is an increase in the partial pressure of the various gases breathed when diving. When it comes to recreational diving, the gas in question is nitrogen. With the partial pressure being high, more nitrogen is able to dissolve into your tissues. It dissolves into your brain’s nerve cells and in your fat tissues cause a disruption in signal transmission where the brain is concerned.

View attachment 403280

The result can be a feeling of euphoria such that everything becomes suddenly funny. Along with this comes absentmindedness, which means that you are not able to monitor your diving instruments. On the other hand, you may begin to feel paranoid, which is often accompanied by anxiety. If not managed properly, this anxiety can worsen. Whichever way you lean the following will be true:
  • You will react slower
  • Simple tasks become hard to complete
  • Judgment, memory and coordination will be affected
  • Going deeper will make things worse
Dealing with Nitrogen Narcosis
To begin with, you will need to recognize it and know its effect on you. Other things will include:
  • Before the dive, get lots of rest and drink plenty of water. Exhaustion slows down your brain and narcosis will worsen that.
  • Do not drink alcohol before the dive. Alcohol and narcosis do not mix.
  • Don’t just suddenly go on a deep dive. Instead, build up your tolerance slowly through regular dives that go deeper each time. Even though you can never become narcosis tolerant, you can learn through experience how to cope with its effects on you.
  • Do not overexert yourself just before a dive. Avoid over exertion during the dive as well since accumulating too much CO2 can enhance narcosis.
  • When descending, go slow so that partial pressure increases slowly. It is a good idea to stop every 10 meters for half a minute.
  • If you are cold, narcosis increases so get warm and then ensure that you stay that way.
  • Keep everything simple and do not task load. It is a good idea to carry your slate and use it. Ensure that you have pre-written phrases on it.
  • Practice your emergency skills and other diving skills well ahead of time
  • Don’t be afraid to bring the dive to an end if you are not feeling too good.
To get rid of the narcosis, simply ascend so that you are at a depth that is shallower thus reducing the partial pressure. You should recover almost immediately. Being a diver, nitrogen narcosis is your enemy.
Always dive with a buddy. I have had partners get Narced and I pulled them up to get them safe. A diver alone or their partner not paying attention can end up in death.
 
Always dive with a buddy. I have had partners get Narced and I pulled them up to get them safe. A diver alone or their partner not paying attention can end up in death.
One more reason why I try to limit my solo diving to 30' or less (don't succeed 100% of the time). The deeper you go the more things that can happen.
 
I just spent 8 weeks in Bonaire diving and hunting Lionfish... 25% Nitrox when hunting in the 150' -160' and normal air down in the 180'-190' range... 30% Nitrox 130' and up... 32% Nitrox for Deco gas...

Jim...
 
I just spent 8 weeks in Bonaire diving and hunting Lionfish... 25% Nitrox when hunting in the 150' -160' and normal air down in the 180'-190' range... 30% Nitrox 130' and up... 32% Nitrox for Deco gas...

Jim...
You might as well come out and say it, "Narcosis affects everyone differently - some more than others. I am part of the 'others' - who are not affected up to 190'." You can believe your open water card qualifies you to whatever depth you want, but the fact of the matter is, it doesn't. You may be qualified through other ways, but it was not through Open Water certification training.

Your whole point about narcosis affecting everyone differently may be true, but to the untrained reader, it sparks cavalier ideas that, "I too am narcosis immune enough to conduct deep air dives." The counter point others raised is that even though there may be difference,it doesn’t matter because no one is completely immune.

o say that a person can't think right after 100' or 130' is bull..
This is so ridiculous! No one is expressing that something dramatic happens between 130-131' (39-40m)! The effect is gradually linear with depth. 60'-130' (28m-39m) is all grey area. There is no mysterious depth where dramatic effect occurs. Someone obviously just arbitrarily picked 60' 100' 130' as cutoffs to differentiate between intensity levels of diving - which also happen have different intensities of narcosis associated with them.

Some have argued that narcosis doesn't occur until some deep deep depth, but if one were open, aware, and honest with oneself, I think you may be able to sense narcosis much shallower than has been argued here. Personally, I believe I have been able to feel it's narcotic effect start in as little as 80' - or even shallower.

The point is that today's open water certification does not include training for best practices deeper than approximately 20m (60') - and I can verify that it hasn't since at least 1995 when I first got certified (I realize a am a relative newbie compared to you). If you want to dive beyond 60' with your ow cert, then go ahead - knock yourself out. But to argue to new divers that ow certification qualifies as 130' training is incorrect and irresponsible.

I agree with the original poster - that whatever the next level after OW is called, it should include some information about narcosis...
 
Last edited:
Just about everyone here knows I'm a oldschool deep air diver... I don't know if you read the whole thread... But, There is a lot of double talk and back tracking in it.. The thread starts off that diving deeper than 60' is un-safe And by 80' you start being Nark'd... Or something close to that.. Then some posters goes on to claim that everyone gets Nark'd at the same depth.. But, Then give a story about having to save their Nark'd friends that were drifting off to death if he didn't save them.. " They were all on air "

I'm not going to sit and let people type Bull Crap and not call them out on it... One of the talking points of mixed gas diving way back in the 80's was letting divers that could not handle deep air dives, to do them... It leveled the playing field I think Steve Belinda said... 90% of divers shouldn't ever go deep... But don't tell me that what we have been doing for 40 years is not safe.. It may not be safe for you...

And My card is only to get tanks filled... Other then that it's just a plastic card good to open doors when I forgot the key..

Jim...
 
Last edited:
I'm pretty sure I got narced this weekend at around 32m. I remember filming some fish, then moving along, and then all of a sudden I went to grab my gopro and it was gone. It was on a lanyard, too. First time I can remember not remembering part of the dive--and especially having a camera slip off and being oblivious to it.

My lingering concern (beyond losing my camera) is how to recognize it in the future. It was kind of unsettling.
 
You might as well come out and say it, "Narcosis affects everyone differently - some more than others. I am part of the 'others' - who are not affected up to 190'." You can believe your open water card qualifies you to whatever depth you want, but the fact of the matter is, it doesn't. You may be qualified through other ways, but it was not through Open Water certification training.

Your whole point about narcosis affecting everyone differently may be true, but to the untrained reader, it sparks cavalier ideas that, "I too am narcosis immune enough to conduct deep air dives." The counter point others raised is that even though there may be difference,it doesn’t matter because no one is completely immune.


This is so ridiculous! No one is expressing that something dramatic happens between 130-131' (39-40m)! The effect is gradually linear with depth. 60'-130' (28m-39m) is all grey area. There is no mysterious depth where dramatic effect occurs. Someone obviously just arbitrarily picked 60' 100' 130' as cutoffs to differentiate between intensity levels of diving - which also happen have different intensities of narcosis associated with them.

Some have argued that narcosis doesn't occur until some deep deep depth, but if one were open, aware, and honest with oneself, I think you may be able to sense narcosis much shallower than has been argued here. Personally, I believe I have been able to feel it's narcotic effect start in as little as 80' - or even shallower.

The point is that today's open water certification does not include training for best practices deeper than approximately 20m (60') - and I can verify that it hasn't since at least 1995 when I first got certified (I realize a am a relative newbie compared to you). If you want to dive beyond 60' with your ow cert, then go ahead - knock yourself out. But to argue to new divers that ow certification qualifies as 130' training is incorrect and irresponsible.

I agree with the original poster - that whatever the next level after OW is called, it should include some information about narcosis...

I'd be interested in which best practices you feel would be lacking in a well taught OW course (I assume we are talking padi OW?) that wouldn't prepare a diver for... Let's say 80FT, or 100ft... Best practices according to which set of standards? I don't know your background philosophy. Some advocate trimix at 60ft, for example.

More specifically, what practices do you personally use at 80ft you wouldn't (and personally don't) at 60ft?

I'm attempting to use those numbers as rough depth ranges. I realize there are no magic cut off depths, particularly between various dive conditions.

My home context is mainly muck/blackwater diving and where I was taught to dive was similar... By the time my OW students experience 13ft deep they are outside of the light zone. Besides a deeper CESA (next breath safely from the surface) there's not much I would teach them regarding task loading or dive planning when moving deeper. Narcosis, (including suspected co2 retention) and confusion all hit in the shallows and need to be learned how to be managed. OW isn't always a 3 day buy a cert course.

Regards,
Cameron
 
Devon Diver
That picture on the front of your article of a lady holding a US Diver SCUBA tank is from a US Diver catalog around 1960
The lady in the picture is the ex wife of an old diving buddy of mine
The march of time is constant they are both retired and well into their upper 60s.
SDM
 
I'd be interested in which best practices you feel would be lacking in a well taught OW course (I assume we are talking padi OW?) that wouldn't prepare a diver for... Let's say 80FT, or 100ft... Best practices according to which set of standards? I don't know your background philosophy. Some advocate trimix at 60ft, for example.

More specifically, what practices do you personally use at 80ft you wouldn't (and personally don't) at 60ft?

I'm attempting to use those numbers as rough depth ranges. I realize there are no magic cut off depths, particularly between various dive conditions.

My home context is mainly muck/blackwater diving and where I was taught to dive was similar... By the time my OW students experience 13ft deep they are outside of the light zone. Besides a deeper CESA (next breath safely from the surface) there's not much I would teach them regarding task loading or dive planning when moving deeper. Narcosis, (including suspected co2 retention) and confusion all hit in the shallows and need to be learned how to be managed. OW isn't always a 3 day buy a cert course.

Regards,
Cameron

Hi Cameron - great questions - actually made me stop and think for a moment.

Before I respond though, I think that most of the instructors on SB seem to hold themselves to a higher standard than the general population of instructors. So with that in mind, I would probably say the majority here are more likely to offer well taught OW classes, which probably would qualify as decent preparation to 100' (30m). As you point out, not all OW is a 3 day buy a cert course - but that is the standard - so when I posted above, that is what I had in mind.

Speaking of no magic cutoff depths, I saw one of John's posts in another string:
This is just a guess, but from my experience in diving at those depths and working with students, if you had asked me to pick a round number for the suggested limit for new divers, I would have picked 60 feet. Why? Because 50 feet seems to be a little too shallow and 70 seems to be a little too deep.
and I noted that I have felt pretty much the same way about the 60-70' depth range. Even 80' doesn't seem that much different than 60' to me, so there wouldn't be much difference between how I did an 80' dive versus 60'. But there are some differences I would start to consider for deeper than 60'.

Some background - I dive primarily in southern california, so the water is cool. so one of the first differences I would suggest, to my students wanting to dive depths deeper than 60', is a drysuit. Personally I dive dry in anything colder than 80 degrees f - especially if venturing deeper than 60' - which is often. Next I would add nitrox and smb. I would also add navigation. Even in my own classes - which I consider to be well taught, and are always longer than a 3 day buy a cert course, I would say many of my students aren't immediately ready to be at 100'. They could do it, as I'm sure many of our sb colleague's students could do it, but just not with the refinement that comes with experience and additional coaching (which is not reflected in an ow card).

Regarding trimix, I have become more and more of a proponent of 100' END (counting O2 as narcotic), although that is a sliding scale as well. I would't say narcosis becomes completely debilitating at 100', but I can tell I have to try and think much harder when I recalculate for changed dive plan even at 90'. For me I feel like trimix noticeably benefits me past 115', but I teach 100'.

I used to think I was perfectly capable of diving deep air when I was doing 200'+ often back in the day, but when I switched to trimix, I realized how much I was missing! It was like going from black and white to color!

Anyway - there is no specific magic depth where something happens - I just think if one is aware and honest with oneself, you can notice narcosis - co2 or otherwise - at much shallower depths than the cavalier diver would like to admit ... and while one can learn information that is good to know for deeper diving from SB and other sources, and one can even extrapolate what they learned from a well taught OW course for use in deeper diving, it is my humble opinion that there is no replacement for well taught additional training ...

- cheers
 
https://www.shearwater.com/products/peregrine/

Back
Top Bottom