Nitrox?

[L13]

Given the recent articles about O2 likely not being narcotic, there are reasons to believe Nitrox may in fact reduce fatigue. The likely mechanism is that increased PO2 reduces the PN2, and there is good reason to expect N2 to be fatiguing both due to narcotic effects and sub-clinical DCS effects.

 

[MaxBottomtime]

there is good reason to expect N2 to be fatiguing both due to narcotic effects and sub-clinical DCS effects.

What good reason would that be? Where did you find that narcotic effects also lead to fatigue?

 

[L13]

What good reason would that be? Where did you find that narcotic effects also lead to fatigue?

Examples of fatiguing "narcotic" effects: alcohol, marijuana, morphine, heroin, hydrocodone, etc.
Basically, all the "depressant drugs". They all often make you feel tired or sleepy.

Also, the times that I have experience nitrogen narcosis specifically, I found experience highly fatiguing. So anything that reduces that nitrogen narcosis would also likely reduce the fatigue.

 

[clownfishsydney]

Comparing dry chamber dives at 18 metres to proper scuba dives at 20 to 30 metres in the ocean is not really a valid comparison.

 

[MaxBottomtime]

Examples of fatiguing "narcotic" effects: alcohol, marijuana, morphine, heroin, hydrocodone, etc.
Basically, all the "depressant drugs". They all often make you feel tired or sleepy.

Also, the times that I have experience nitrogen narcosis specifically, I found experience highly fatiguing. So anything that reduces that nitrogen narcosis would also likely reduce the fatigue.

Nitrogen narcosis goes away if you ascend a bit. Are you saying it gives you fatigue that stays with you?

Comparing dry chamber dives at 18 metres to proper scuba dives at 20 to 30 metres in the ocean is not really a valid comparison.

Another study involved actual dives.

 

[Angelo Farina]

Remember that narcosys is often caused by CO2, not by nitrogen. And CO2 is caused by over exertion and poor ventilation.
This makes obvious that after an episode of narcosys which wad triggered by CO2 accumulation one feels tired.
In these analyses one must always take into account several factors which interact in your body.
I liked the Bulhman approach of adapting his deco algorithm to exertion (or effort), as this is a very important factor interfering with nitrogen diffusion through the body.

 

[OMyMyOHellYes]

presbyopia may be a factor.

What does religion have to do with EANx and computers?

 

[OMyMyOHellYes]

This theory has been thoroughly debunked.

What protocol was used in debunking the theory that Ross' dad felt better after EANx dives? Over what period of time were the studies conducted? How much diving, with and without EANx, and for what times and depths, did Ross' dad devote to testing whether he felt better after his EANx dives?

 

[OMyMyOHellYes]

So I'm just an occasional diver and as I said am reluctant spending a lot of time, energy and money getting certifications and equipment i probably will never use or need, except maybe a dive computer.

Time and energy invested for EANx cert is minimal. Maybe an hour of classroom. Other than having a chance to dive, an in-water EANx training dive (IMNSHO) is pointless: you learn how to do the pre-dive stuff and dive like any other dive, but with different NDT and surface intervals. Your computer will tell you what those are.

My course summary (or at least my takeaways):
Discuss how pressure builds with each 10M of water. Understand a very minimal amount of theory as to percentage of O2 in breathing gas and how that relates to depth and O2 limits and consequences like O2 toxicity. You'll hear things like PPO 1.4 and 1.6 and know one is the limit (don't go past) and the other is the hard limit (deadly bad things can happen really quick if you go past). Work through how the numbers run through the formula and establish max operating depth (MOD) - this was all just to conceptualize - you probably will never see those calculations again. Your computer will tell you or there's likely a chart at the fill station that says your "MOD at XX% O2 is YYY".

The operational part of the course entails how to test O2 concentrations using an analyzer (easy) - in recreational environments to verify the MOD from a chart on the wall and how to set up your computer (so may need the computer first)

Summary: EANx Rec = know how to test O2 concentration, verify/setup dive computer for O2 concentration, label tanks, dive.

It's good stuff to know in any case. And it's a one-time expense. And you get more plastic. I don't particularly think more plastic's a good thing.

 

[Blackcrusader]

If your dives are being ended because of hitting NDL, then nitrox is going to help. If your dives are being ended because you hit a gas limit then it won't extend your bottom times. Only you know from your experience which one you hit first.

There are other physiological benefits from diving nitrox without extending your bottom time that you can research on this forum as well, but specific to your question, it all depends on which limit you hit first.

Yes nitrox is good to have. ATM where I am diving they do not offer nitrox just 21% air.


On this dive ( my second dive today ) I was using 21%. If I had been using nitrox my time to NDL would have been longer but dive time the same if I kept same dive profile. As it was 3 other divers on the same dive were back on the boat and taken to shore after 50 mins as they used up their gas a lot faster. My DM and I continued and finished this dive today with 75 minute + dive time. The same dive on nitrox would have had the same dive time.

Let's say you have a dive to 30m and use nitrox. You have a longer NDL time but as you stay deeper you use more gas. So you need to ascend so as not to get too low on gas. Your total dive time may only be 45 minutes.

My dive time might be 60 minutes if I use less gas than you do