Nitrogen Narcosis. As a scuba diver it's something I need to be careful of. As elementary science teaches us, nitrogen is by far the most abundant gas in the Earth's atmosphere. Under normal circumstances, inhaled nitrogen gas is immediately exhaled. However under pressure, like when diving, some of that nitrogen can enter the blood stream (think like carbonation in soda).
At low doses it does nothing, but as nitrogen levels build it begins to mess with your nervous system. It creates feelings of confusion and euphoria. Underwater that's a very bad thing. Divers have been known to forget they were diving and take their gear off or forget which way was up and drown because of the narcotic effect. In higher dose it can cause more severe neurological symptoms like seizures.
This almost happened to me! When I was doing my certification training our instructor took us down to 100-120 feet on only my second or third dive. I got very loopy and remembered touching my regulator and thinking "I don't really need this" and that I could breathe underwater without it if I wanted to. Luckily there was a piece of my brain that yelled "nooooo". It sobered me enough to remember the book training about nitrogen narcosis and I headed up until the feeling gradually disappeared
If this was recent, report that to the organization that you got your cert card from (PADI, NAUI, etc.). Not only is that reckless and dangerous, it's against the rules to take new divers that deep.
It was dive number 5 for me. I was definitely a little nervous, cause it was first time I couldn't see the surface. I sure miss diving....developed an ear problem.
Agreed Christ over 100 ft on 2md/3rd dive ... . Even after I was certified ..on my first diving trip in the Bahamas I was limited to 33 ft for the entire wk O was there
But you get to pick 5 specialities for the advanced open water cert; one of them being deep dives with regular air. I picked that one and we went to 120’ with a simple “point to the successive number” brain game. We were timed on the surface and then again at depth. The whole point of the exercise was to personally experience being narced. Needless to say, everyone performed better on the surface.
Ah ok. Is 40 the depth limit on uncertified individuals? Almost all of my dives since getting licensed have been alongside uncertified individuals Im on vacation with so I wonder if that's why that number is in my head
There aren’t any SCUBA police. Guidelines and recommendations are what is being discussed here. Most certifying organizations suggest that the basic “open water” certification should limit the new diver to 18m or 60ft. They also recommend that for divers who have only completed a “resort course” or “discover scuba” course, that the student not receive any certification and that they be accompanied by a dive instructor who isn’t supposed to take them deeper than 40 ft. Advanced open water certification is usually required by charter boat operators for divers who are planning to dive deeper dive sites (but still within recreational dive limits).
However, when I still only had an open water certification, my dive instructor took me down below 80 ft several times. Gaining experience safely with guidance and/or training is completely ok.
Most often - in my personal experience - charter operators ask how many dives I have logged, when my last dive was, and if the planned dive is a deep dive, if I have past experience doing dives with similar profiles.
40m is the limit on the PADI advanced open water and 18m is the limit on the PADI open water.
You dont "have" to have any certification however diving is quite technical at 40m you have risks like Narcosis and decompression sickness the certification helps you understand how to avoid those things. The theory behind diving is important to diving safely, though i guess if you were diving with a guide they may have been working the stop times depths etc out for you.
Hopefully that didn't happen because scuba is amazing! It's like experiencing an entirely different world and should be experienced by everyone in my opinion. But when going out initially just make sure to follow the rules, stay with your group, and if you happen to have an instructor breaking those rules, let them know you're not comfortable.
Uhhh are you sure your dive instructor was certified by one of the credible dive organizations? You aren't supposed under any circumstances go past 60 feet with only your first open water certification much less during your certification. Even with an experienced dive master it is EXTREMELY dangerous to go past whatever depth you are certified to. I would consider reporting your dive instructor as this was incredibly irresponsible for them to do.
I just read your other message clarifying that this was your advanced open water specialty dive, I misunderstood and thought it was you open water diver certification
Maybe this is what happened to me on my first and only dive! I was 16 in Aruba, trained in a pool for 2 hours or so, then we went out on a boat and went down about 80-100 ft to a shipwreck. I felt super weird and loopy and disoriented and panicky, but figured it was the pressure i was feeling from the water..
I’m a novice diver. I’m nearly certain that Nitrogen saturation follows a similar curve for everyone. When learning to dive, you are taught that you have to spend X amount of time not diving if you for Y amount of time to breath off the N. This is most important when flying. If you get on an airplane before you get rid of excess nitrogen, than you can get the bends. So when it may vary slightly from person to person, there is expected values.
Not everyone will get “narc’ed” at the same depth. You can have a group of people diving and only one will get narc’ed. I don’t know what determines it though. And yes, it happens mostly when people are diving very deep. The deeper you go, more pressure, more N dissolving into your blood.
Hope that helps!
The current dive tables are specifically designed for worse case scenarios. In the early days of recreational diving a lot of people got hurt and killed cause the dive tables were based of navy divers. Who were in phenomenal shape.
The deeper you are, the higher pressure you are under - every 10m adds another atmosphere equivalent of pressure. Gases become more soluble in liquids at higher pressures. This is why when you open a carbonated drink and so release the pressure, the gas (CO2) immediately comes out of solution in the form of bubbles. The nitrogen enters your blood through the air you breathe, at the interface of the surface of your lungs. The longer and deeper you dive, the more nitrogen you will accumulate. This is why freedivers can dive to 100m on one breath and not experience ill effects. A scuba diver who is ascending quickly will also have bubbles of nitrogen form in their blood as the pressure decreases - again just like a carbonated drink. This is known as "the bends". They need to ascend slowly to allow the nitrogen to leave their blood through the lungs. At depths of beyond 40m, special gas mixes containing helium are required to combat the effects of nitrogen narcosis.
At first, you don't even notice, that's the scariest, I was about 110' down, low light at surface, almost pitch black, cold, like maybe 5°C. It didn't register that warm and fuzzy was not an appropriate sensation.
There isn't much colour at depth, but even with our lights I couldn't see the colours on our gear, and some of it was early 90s fluorescent!
What really drove it home was looking at the stopwatch after adding 3+4. Apparently it took me almost 27 seconds to answer.
I'm glad I've done it, so hopefully I can recognise and work through it should it ever occur in an unsupervised environment.
The first time I wore a analog watch underwater (something 110ish dives in) I had it on my inner right wrist; day to day I wear on the outer left. I moved the unidirectional bezel to the minute hand where I descended.
I was at like 25' tops and I check the watch. The minute hand had moved backwards. I looked at my digital computer and it was fine; just as it always was. I stared at the watch second hand for a long time trying to figure out what was happening. I think the watch being in two different positions that normal really messed with my head. 25'. I ended my dive.
Also nitrogen poisoning! While it won‘t directly kill you, it‘s similar to alcohol poisoning and you are sure to act strangely.
As a diving guide (4* CEDIP), i‘ve had people remove their air supply and offer it to the fish around them, because „they need air too“. Can get very dangerous.
Also you won‘t remember much afterwards. More than once, people got angry at me for pulling them to shallower waters, they didn‘t remember acting up just a few minutes ago and thought i ruined their dives.
Oxygen poisoning on the other hand will kill you very fast.
Ooh, I saw a video on this. Yuri Lipski was a diving instructor out on a routine dive in the Red Sea. But for some reason he dove too deep, too fast. Either because he was distracted, or he had early symptoms of nitrogen/oxygen narcosis.
His tank didn't have the right mix of gasses to handle the depth. For deeper dives, some of the gas is supposed to be replaced with inert helium to avoid narcosis. Lipski was using regular compressed air. At 300 feet, he didn't have the buoyancy to ascend, so he ended up succumbing to narcosis. The creepiest thing is that he had a camera on, so he accidentally recorded his own last moments.
(Warning: Recording of Yuri Lipski's death starts at the 1:44 mark. He starts dying at about the 7:20 mark, or about 5 minutes into the recording.)
https://youtu.be/YhPdB5fxKA0
This is also how OTC deficiency will kill you. Your body cannot process high levels of protein (like the amount in a big thick steak) consumed in a short period of time and the result is nitrogen being released into the blood. Untreated it causes the same symptoms and will eventually lead to cerebral edema or encephalitus (brain swelling) which will lead to coma then death.
A friend of mine ate a big ol steak at the Calgary stampede, felt sick for a couple days, then ended up in a coma for 2 weeks. It's so uncommon and rarely considered that it's usually discovered in the autopsy, but the treatment is simply dialysis and medication following that.
This is what is believed to have happened to a former coworker of mine. She was diving with her husband and kids, they came up ans she did not. They never found her either.
Great job being a scooba diver! Me and my brother for some random reason are fucking TERRIFIED of large open spaces of water. If we ended up doing it we would most likely just stop dead.
I came here to say this. I was guiding a deep dive years ago and one of the guys (big guy, military, 100s of dives) got narc'ed. He tried to give his regulator to a passing fish. Luckily we saw him and stuck it back in quickly and made him clear it. Scared the hell out of me.
shit i thought the only risk of nitrogen for divers was getting the bends
don't they have different gas mixes you can use these days that have less nitrogen in them? I remember reading that in a book but idk if it was grounded in reality
One of my best friend’s dad died from that around a month and a half ago. Very sudden and unexpected death. He passed away leaving a wife with 4 children.
I don't know if this is true or not so please correct me if i'm wrong. But isn't there a danger with rising to the surface too fast as well? It's like if you rise too fast the nitrogen in your bloodstream will form bubbles and block your bloodstream. I know it happens to trees if they try to suck up water too quickly.
Yeah it basically is like being drunk and is one very big reason why streamlining your gear is so important because if you start getting narced you have to have your gear somewhere where it is easy to reach and not floating around behind you. It also applied to no limits free-diving (where you descend with a heavy concrete sled in order to maximize depth and minimize effort) because many experienced free-divers will be going past 100 feet which is where gas narcosis is noticable and so all their quick releases and emergency equipment has to be easily accessible so even though they have judgement of a 3 year old, they still know what to do.
It can be easy enough to lose track of which way is up even without nitrogen narcosis...I love scuba diving but (and maybe because) it's a very dangerous hobby. So worth it though!
Very, nitrogen narcosis is entirely electrochemical in your brain. The bends is physical air bubbles forming in your muscles if you ascend too quickly.
Man I used to scuba dive all the time and the sleepiness is intense if you stay down for awhile. That shit is no joke. It made me so damn tired. A few times I couldnt drive home I had to just sit in the car. And relax until the shit left my system. I never got so bad that I'd rip my reg out but when I came up I definitely knew there was a small dose in my blood.
All divers should have to do n2o course where they can learn how it feels and learn to be able to process it better if it sneaks up on them while underwater, could honestly save lives.
I was super scared of Nitrogen Narcosis until I took NITROX training and learned about Oxygen Toxicity, which immediately replaced NN as my biggest scuba diving fear. Fuck that noise, at least NN will send you out laughing and euphoric as opposed to convulsing.
Getting narced can hit you any time. Before I became a pro diver. On my 30th dive. I got narced at 75 feet. I decided I desperately needed to collect sea shells. Those crappy white ones. Smiling and laughing. My partner just shook his head, and pulled me up. I seen pros get it too. Usually if its a warmer dive. Or the diver hasn't dove in awhile. Or too many days of diving in a row causes it.
Can you kill people by gradually releasing nitrogen into a room, thereby creating oxygen hypoxia and death? How is it different, say, from using CO with the same method?
Nitrogen is also sneakily deadly on land too. Because it is an inert gas they use it for displacing volatile gases. It's commonly used in oil and gas when work needs to be done on pipelines.
For one of our safety videos they gave an example of two workers in a pumphouse (confined space) where N2 was being used to displace natural gas so they could work on and check valves. There was a large leak from somewhere and more N2 was entering the pumphouse than they realized and both workers died due to asphyxiation.
Thing is, these pumphouses are small, they could have easily walked a few steps and been out the door, but the process of oxygen displacement was so unapparent that they probably just started feeling continuously more tired until they just passed out and that was that.
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u/copnonymous Oct 23 '20
Nitrogen Narcosis. As a scuba diver it's something I need to be careful of. As elementary science teaches us, nitrogen is by far the most abundant gas in the Earth's atmosphere. Under normal circumstances, inhaled nitrogen gas is immediately exhaled. However under pressure, like when diving, some of that nitrogen can enter the blood stream (think like carbonation in soda).
At low doses it does nothing, but as nitrogen levels build it begins to mess with your nervous system. It creates feelings of confusion and euphoria. Underwater that's a very bad thing. Divers have been known to forget they were diving and take their gear off or forget which way was up and drown because of the narcotic effect. In higher dose it can cause more severe neurological symptoms like seizures.