Nitrogen Narcosis and Nitrox

[Jason Ooi]

Helium is none narcotic good for tech trimix dive.

 

[*Floater*]

Question is does diving nitrox or trimix lower the effect of narcosis?
In the SSi nitrox book it says" You should not count on experiencing less narcosis or impairment". But if this is the case how do deep (50m+) divers deal with it?
What are your personal experiences? Is it a measurable effect that you caculate like EAD or PPN ?

For 50m+ dives nitrox with over 21% O2 is not a good choice because the ppO2 would be undesirably high (O2 is toxic at high partial pressures), so for those dives you should stick with either just plain air and accept the narcosis, or ibetter yet use trimix.

Whether O2 contributes to narcosis is unknown, or at least I'm not aware of any research to prove it one way or the other. I recently watched a DVD called Mysterious Malady distributed by GUE.com which addresses this question to at some length, and the world-class experts on that DVD all said they didn't know the answer. The research just isn't there yet. However, it's probably prudent to assume that nitrox is as narcotic as air just to be conservative, at least for 21%+ O2 nitrox mixes.

 

[Jason Ooi]

You are absolutely right. 50m+ trimix dive is the good choice.
Nitrox 21% 1.6 ppo2 maximun depth is 66m 7.6ata

For 50m+ dives nitrox with over 21% O2 is not a good choice because the ppO2 would be undesirably high (O2 is toxic at high partial pressures), so for those dives you should stick with either just plain air and accept the narcosis, or ibetter yet use trimix.

Whether O2 contributes to narcosis is unknown, or at least I'm not aware of any research to prove it one way or the other. I recently watched a DVD called Mysterious Malady distributed by GUE.com which addresses this question to at some length, and the world-class experts on that DVD all said they didn't know the answer. The research just isn't there yet. However, it's probably prudent to assume that nitrox is as narcotic as air just to be conservative, at least for 21%+ O2 nitrox mixes.

 

[rookers]

Helium is none narcotic good for tech trimix dive.

More pedantically:

Narcotic factors of gases (relative to N2):

(Chemical sign, name, factors (divide by / multiply by) )

He, helium, 4.26 / 0.23
Ne, neon, 3.58 / 0.28
H2, hydrogen, 1.83 / 0.55
N2, nitrogen, 1 / 1
Ar, argon, 0.43 / 2.33
Kr, krypton, 0.14 / 7.14
Xe, xenon, 0.039 / 25.64

So as one can see, all these gases are narcotic to a certain degree. Neon and Helium are the least. Neon has sometimes been used in exotic (expensive) diving applications as the 'inert' gas in a mix (neox and neoquad) because it has better decompression (in short bounce dives) and thermal properties than helium. Hydreliox/hydrox is also sometimes used, though mixing hydrogen and oxygen must require Inconel balls and a duct taped sphincter. Xenon is used as an anasthetic as it is quite dopey.

 

[Packhorse]

If the narcotic effect of all these gases are known then why isnt O2?
Wow people really mix H & O in a dive tank?
You would want to open the vavle real slow I guess.

 

[MikeFerrara]

If the narcotic effect of all these gases are known then why isnt O2?
Wow people really mix H & O in a dive tank?
You would want to open the vavle real slow I guess.

The estimates are based on the properties of the gas alone...Lipid solubility, is that the term I'm looking for?). If we go by that, O2 is very narcotic, however, it's not inert. It's matabolized.

I think the narcotic properties of O2 would be hard to measure for several reasons. Besides, does it really make much of a difference? When diving a nitrox mix with much of an increase in fO2, can you go deep enough to really find out? Put another way, when diving "deep" on nitroc, your still going to have lots of N2.

With trimix on deeper dives, the O2 is still kept within limits and whether we calculate END treating O2 as narcotic or not, the difference isn't all that great.

I treat O2 as narcotic in my calculations for two reasons. First it's the more conservative. Consider that our calculations don't consider CO2 at all. Second, it simplifies the math.

 

[MikeFerrara]

If you dive AIR time tables while on Nitrox it should lessen the effects of Nitrogen Narcosis;

How does that work?

 

[Walter]

How does that work?

LOL! Amazing!

 

[H2Andy]

If you dive AIR time tables while on Nitrox it should lessen the effects of Nitrogen Narcosis

not quite

diving nitrox on air tables gives you a greater safety margin as to decompression
issues, since you are essentially diving "shallower" by diving with Nitrox (as compared
to air, which you are planning your dive with).

but there's enough nitrogen in nitrox to really give you a good buzz, equivalent to air, at any depth

 

[Albion]

but there's enough nitrogen in nitrox to really give you a good buzz, equivalent to air, at any depth

until you've dived trimix with a buddy without helium you dont fully understand the difference. its like being the designated driver, your waving its time to turn and they dont even know your there