To Nitrox or not to nitrox ,Why and how ?

[elan]

I teach Nitrox.

So what is the advantage, if it costs more?

Several.

Allows extended bottom times at moderate depths (look at the charts for both mixes, and "run the numbers").

Reduces the feeling of fatigue in repetive diving (live aboards, or places like Bonaire where you can dive 5-6 times/day) (no "scuba nap").

No it does not .

Reduces incidence of nitrogen narcosis.

No it does not

The time to sit in a course takes about 2 hours. All of the above is discussed in great detail, as well as analyzing a cylinder. I wish I had done it right after I had been certified.

On the gear, if you have your own gear, everything needs to be O2 cleaned.

No it does not need to be for those percentages used for rec diving ( below 40%) Only the tank and the valve if it is used for pp blending.

This simply means impurities are removed, and some of your O-rings may need to be switched out. You don't use silicone lubricants any more, after switching over (tends to oxidize, with resulting off gas being toxic).

Hope this helps.

Of cause as an instructor you can tell me I'm completely wrong

 

[elan]

Yes, narcosis can affect different people differently, and even though some symptoms of this can be seen
as shallow as 100 feet, narcosis is usually seen when diving to depths beyond the MOD of common EAN mixes.

I see it on every dive below 70-80 ft whether on EAN or on air, and it is well above the MOD.

Some people "think" they do not have it.

 

[oldogre]

To pop in a question, as we get older our lungs become less efficient, at 78 I prefer Nitrox, is this reasoning correct?

 

[DazedAndConfuzed]

Wouldn't drinking a ton of booze before a dive alleviate the effect of narcosis? The alcohol will be metabolized by the liver into glyceride flowing in the bloodstream, thus any intake of nitrogen will combine with that to form nitroglycerin.

 

[MaxBottomtime]

I teach Nitrox.

Lots of misinformation and opinions on this post.
Reduces the feeling of fatigue in repetive diving (live aboards, or places like Bonaire where you can dive 5-6 times/day) (no "scuba nap").
Reduces incidence of nitrogen narcosis.

Whick agency do you teach for? Every texbook I've read says that the reduction of fatigue is a placebo effect and there is no evidence that nitrox will reduce narcosis.

 

[Rhone Man]

Whick agency do you teach for? Every texbook I've read says that the reduction of fatigue is a placebo effect and there is no evidence that nitrox will reduce narcosis.

That is the modern thinking (which is the reverse of the older thinking). I don't think anyone has a definitive answer on either.

The lipid solubility of oxygen suggests it should be more narcotic that nitrogen. But unlike nitrogen, our bodies can metabolise oxygen, making it potentially less likely to cause narcosis. But given the physiology of narcosis is not well understood, it is really speculation. What is clear is that it doesn't seem to make much difference between nitrox mixes and air.

The fatigue question is also open for debate. Anecdotally, lots of people swear by it. Others say it is rubbish. I tend to believe that microbubbles in the bloodstream are a causative factor in fatigue, so it stands to reason that reducing the incidence of microbubbles through lower ppN2s ought to reduce fatigue for a similar dive profile.

 

[theduckguru]

The statistics indicate the occurance DCS with of Nitrox vs air is very minimal. So I not certain I support your Nitrox vs air microbubble reduction theory.

That is the modern thinking (which is the reverse of the older thinking). I don't think anyone has a definitive answer on either.

The lipid solubility of oxygen suggests it should be more narcotic that nitrogen. But unlike nitrogen, our bodies can metabolise oxygen, making it potentially less likely to cause narcosis. But given the physiology of narcosis is not well understood, it is really speculation. What is clear is that it doesn't seem to make much difference between nitrox mixes and air.

The fatigue question is also open for debate. Anecdotally, lots of people swear by it. Others say it is rubbish. I tend to believe that microbubbles in the bloodstream are a causative factor in fatigue, so it stands to reason that reducing the incidence of microbubbles through lower ppN2s ought to reduce fatigue for a similar dive profile.

 

[Dr Wu]

You can technically say the percentage does change....

Yeah, um...No. You cannot do that. No.


OP, as you can see there is a lot of of incorrect information thrown around on this site.

Take the class and think for yourself.

Nitrox is very easy for most people to understand.

 

[Dr Wu]

To pop in a question, as we get older our lungs become less efficient, at 78 I prefer Nitrox, is this reasoning correct?

If you are still diving at 78 you have no need to ask for advice.

There is no doubt you are doing it correctly.

 

[String]

I teach Nitrox.

OK...So do a lot of posters on this thread.

Lots of misinformation and opinions on this post.

Indeed and you just added to it.

For a standard Nitrox mix of 32% oxygen, that means the nitrogen goes from 79%, down to 68%. This, in turn, means you have less nitrogen molecules in your blood stream. So if you have less nitrogen molecules, it takes less time to get rid of them.

vs air at the same depth.

Reduces the feeling of fatigue in repetive diving (live aboards, or places like Bonaire where you can dive 5-6 times/day) (no "scuba nap").

No it doesn't. Studies have been done and not a single one has found any statistically valid correlation. No agency that im aware teaches this.

Reduces incidence of nitrogen narcosis.

No it doesn't. No agency teaches this. There is no evidence what-so-ever to back this up. Where do you get this from if you're supposedly an instructor?

On the gear, if you have your own gear, everything needs to be O2 cleaned. This simply means impurities are removed, and some of your O-rings may need to be switched out. You don't use silicone lubricants any more, after switching over (tends to oxidize, with resulting off gas being toxic).

Again no it doesn't. If you're doing standard recreational levels of diving (ie nitrox <40%) which is the topic here your regs are fine out of the box. Your BCD does not have to be O2 cleaned!
If you own a tank and do partial pressure blending that needs to be cleaned - that's the only item that needs it. If you're using membrane, continuous flow or pre banked not even that needs to be.

You just added to the misinformation whilst claiming to be an authority.