Do you think Nitrox is a deep diving gas?

[carrielsal]

I was taught that nitrox reduces narcosis and therefore it was better to dive with a nitrox mix in the 30-40m range by my Deep instructor so yes, it was kind of sold to me as a "deep" diving gas in that regard early on as he said it would be safer as I would be less narced.

hmmm...The SSI manual states:
Until such time as researchers can verify what impact, if any, Nitrox has on narcoses, you should not count on experiencing less narcosis or impairment when diving Nitrox than you do when diving air at comparable depths.

Carrie

 

[Sas]

hmmm...The SSI manual states:
Until such time as researchers can verify what impact, if any, Nitrox has on narcoses, you should not count on experiencing less narcosis or impairment when diving Nitrox than you do when diving air at comparable depths.

Carrie

I think this is not specific to SSI. My TDI nitrox course taught the same. Is there any agency that teaches that nitrox reduces narcosis?



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[Thalassamania]

The issue is really this: It is unknown if oxygen is as narcotic as nitrogen, if it is then there really is no difference.

Because increased oxygen in the mix forces the diver to a shallower MOD (whatever the ppO2 you like is) the narcosis differences are not very pronounced, even if they existed. Let's say that there is an equivalent "narcosis" depth that is equal to the equivalent air depth. In that case, for EAN-32 at 1.6 ata (132 fsw) there's an equivalent air depth of 93 fsw. How much difference in narc for the 39 feet? In that case for EAN-36 at 1.6 ata (114 fsw) and the equivalent air depth of 86 fsw. How much difference in narc for the 28 feet? but still?

 

[gcbryan]

The issue is really this: It is unknown if oxygen is as narcotic as nitrogen, if it is then there really is no difference.

Because increased oxygen in the mix forces the diver to a shallower MOD (whatever the ppO2 you like is) the narcosis differences are not very pronounced, even if they existed. Let's say that there is an equivalent "narcosis" depth that is equal to the equivalent air depth. In that case, for EAN-32 at 1.6 ata (132 fsw) there's an equivalent air depth of 93 fsw. How much difference in narc for the 39 feet? In that case for EAN-36 at 1.6 ata (114 fsw) and the equivalent air depth of 86 fsw. How much difference in narc for the 28 feet? but still?

It's may "force" a diver to a shallower MOD but it rarely forces a diver to a shallower depth so that's a rather moot point. Most divers probably weren't going to 187 fsw (air MOD) in the first place. They are going to dive at the depth that there is something to see regardless of what they are breathing.

 

[MauiScubaSteve]

How do you train for using higher oxygen levels? It seems like just a physiological response where you instantly pass out without any warning: how can training overcome this?

Ahhh tundra hopper, is that really the question?

Step 1 - use 1.6 PPO to calculate Max normal diving bottom

Step 2 - use 1.8 PPO to calculate Max contingency depth

Step 3 - if there is more than normal diving stress or strain adjust upward as neccessary

Historical data that I am pulling from vague memory - NOAA working divers did thousands of 1.6 PPO dives without statistical increase in O2 incident as I recall it. The actual definition of working that was used for those dives was more effort than my normal diving as far as I read it. If they have adjusted upwards (due lawyers probably) I think it's probably just as well because the typical modern human seems to have a weaker more fearful brain compared to the divers who the science was calculated with, and it's well known that fear is the real killer.

 

[Tigerman]

Ah one day they'll be endorsing solo diving ... probably the day they see SDI is making good money from their solo course

Im planning to "spread the wealth" and do the SDI solo diver course soon. Doesnt hurt to have it, does it?

 

[John_B]

Ahhh tundra hopper, is that really the question?

Hey, there, I'm the "Grasshopper" around here! It says so right on my badge!

 

[Joe-Diver]

Why does this poll add up to 144%?

 

[HowardE]

Why does this poll add up to 144%?

It's a multiple selections permitted poll. So it can exceed 100%

 

[MXGratefulDiver]

Should I get my Spare Air filled with 32%

No ... fill it with 100% oxygen. That way you'll only need small sips at a time, and it'll last longer ...

... Bob (Grateful Diver)