Nitrox question

[Wijbrandus]

That answer works for me.

 

[StSomewhere]

If they do partial pressure nitrox fills, they should have O2 compatable air. So your supply is limited by the number of shops that do partial pressure nitrox fills

Yes, the closer you are to great diving, the more dive shops there will be and the more options you will have. But even as far as I am from deep water, I have two LDS's that do Nitrox fills.

Its traveling to deep water with my tanks that worries me, who knows if some dive shop you've never heard of really understands nitrox? You basically have to conduct an interview before you let them have your tanks, or you may be having them O2 cleaned when you get home...

 

[recdiver]

For me I rather do my deep dive first on 32% and lessen my nitrogen loading. All my subsequent dives get progressively shallower (and if I can't dive again on 32%) then 21% is the choice.

I'm not sure what depth you advocate diving 21% on. For me I keep it to under 100'. Where as up to 32% I'll go deeper.

I'm curious...if you limit yourself to 100fsw on air why are you willing to go deeper with 32%? Do you feel that you have a clearer head with 32%?

 

[Otter]

Lets clear up two things REAL QUICK. Nitrox DOES NOT allow you to go deeper, it allows your dive longer. In fact, NITROX causes you stay shallower than you would with air. The higher the concentration of O2, the shallower you go. Again, you will go over this in your class and learn how to calculate your Maximum Operating Depth (MOD).

Secondly, NITROX does not provide 'relief' from narcosis. Why? Because O2 is considered as narcotic (some theories suggest even more so) as Nitrogen.

Nitrox replaces some of the nitrogen in your breathing gas with O2 which extends your no decompression limits (plus side) while slightly increasing your dive complexity by moving the maximum depth you should dive to something less than the recreational limits of 130 feet.

BTW: the MOD of EAN32 is 111 feet at a PPO2 of 1.4.

 

[recdiver]

Lets clear up two things REAL QUICK. Nitrox DOES NOT allow you to go deeper, it allows your dive longer. In fact, NITROX causes you stay shallower than you would with air. The higher the concentration of O2, the shallower you go. Again, you will go over this in your class and learn how to calculate your Maximum Operating Depth (MOD).

Secondly, NITROX does not provide 'relief' from narcosis. Why? Because O2 is considered as narcotic (some theories suggest even more so) as Nitrogen.

Nitrox replaces some of the nitrogen in your breathing gas with O2 which extends your no decompression limits (plus side) while slightly increasing your dive complexity by moving the maximum depth you should dive to something less than the recreational limits of 130 feet.

BTW: the MOD of EAN32 is 111 feet at a PPO2 of 1.4.

I don't know if this was for my benefit but it was unneccessary (but still appreciated). It does however provide the basis for my question to OE2X...if you limit yourself to 100fsw on air why are you willing to go deeper with 32%?

 

[wedivebc]

Secondly, NITROX does not provide 'relief' from narcosis. Why? Because O2 is considered as narcotic (some theories suggest even more so) as Nitrogen.

.

You have any proof of that?

 

[D_O_H]

You have any proof of that?

I'm in the process of taking my nitrox course and became interested in this topic. PADI teaches that O2 is narcotic. People seem to agree (e.g. The Physiology and Medicine of Diving" by Peter Bennett and David Elliott, 4th edition, 1993) and disagree (e.g. http://divermag.com/archives/dec96/divedoctor_Dec96.html) about whether this is true.

Narcosis affects people (or not) in such different ways, it's probably pretty hard to get a handle on whether someone is narc'd and, if so, by how much.

I wonder if anyone has done a study of, say, reaction times at depth on EAN and air? This is something of a thread hijack, but if anyone has seen such a study, please share it.

 

[lamont]

You have any proof of that?

The time both me and my buddy missed the turnoffs to the dolphins at the boundary cable around alki cove 2 and swam halfway around the boundary cable before registering that we'd *WAY* overshot our turnoff and needed to turn the dive. 100 fsw, limited visibility. Had a nice + solid narc hit on for both of us.

I've done numerous air dives to 100 fsw and numerous EAN32 dives to 100 fsw, and I can't tell the difference. I always feel the onset of (perceptable) narcosis below 85 fsw.

You can probably find the scientific references to O2 narcosis by doing a search on this site.

 

[wedivebc]

The time both me and my buddy missed the turnoffs to the dolphins at the boundary cable around alki cove 2 and swam halfway around the boundary cable before registering that we'd *WAY* overshot our turnoff and needed to turn the dive. 100 fsw, limited visibility. Had a nice + solid narc hit on for both of us.

I've done numerous air dives to 100 fsw and numerous EAN32 dives to 100 fsw, and I can't tell the difference. I always feel the onset of (perceptable) narcosis below 85 fsw.

You can probably find the scientific references to O2 narcosis by doing a search on this site.

Actually I have done plenty of searches and plenty of reading on the subject and since Otter spoke with such conviction on the topic I thought maybe he had found some proof to finally put this issue to rest. I certainly have not found anything concrete to say with such certainty that oxygen contributes to narcosis.

 

[Scuba_Steve]

OK Wedive, it's put to rest for us then.

Of course you're welcome to think as you wish as well

I would however think you are also in the minority, but if it floats your boat.....we're happy for you.

It certainly doesn't help narcosis, so the rest of us would chose to err on the side of caution.

Fair enough?

Regards.