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howdy
I have a problem: There are facts and some assumption out there which do not fit
together, as far as can see:

1) The need for decompression results from soluted gases in body tissues
2) Oxygen has a higher solubility in water and oil than nitrogen
3) The specific narcotic behaviour of a gas increases with its solubility (Meyer
Overton)
4) Test, using nitrox instead air, have shown no influence on the divers
behaviour in terms of nacosis.     This resulted in: there is no END for nitrox
5) Nitrogen (and helium) are responsible for decompression, which resulted in
the EAD prinzip

I think, that one of those five points must be wrong.

I assume, that at least 1) and 5) are correct, since 1) is proven for a long
time; and 5) nitrox (with less nitrogen than air) increases the no-decompression
limits, if not, most of us would have had the bends meanwhile. 2) is also
correct since it is the result of experiments.

Using those three, I think, 3) and 4) do not fit

Number 5) seems to demonstrate that oxygen obviously is not in solution; if it
were, nitrox would not make sense, since replacing one soluted gas with another
(with an even worse one) would not help on the no-decompression limits. But
then, if oxygen is not soluted, how can it contribute (like nitrogen) to
narcosis. Well, if oxygen contributes to narcosis, then the Overton-theory is
wrong, if it does not, then the narcosis tests are wrong and there should be an
END for nitrox. I guess, this is the truth, since for a shallow depth, where a
real significant change in the nitrogen contents can be achieved, the is no
narcosis anyway. At deeper depth, where narcosis is obvious present and where
the tests should performed, hot nitrox (low on nitrogen) cannot be used because
of the PPO2. this would propose, that there is an END for nitrox, however it is
not real measurable and the test are therefor invalid.
Also, if seems to be obvious, that narcosis and decompression theory cannot be
made on the assumption of solubilities like water=blood and oil=fat, al least
not for oxygen. However, from all the oxgen in the air, that we breath, only 20%
(4% out of 21%) is bond to hemoglobin. The rest should be capable to diffuse
like nitrogen and go into physical solution and should therefor contribute to
decompression.

Is there an explanation out there? Can someone see more?

Thanks, Bernd

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