[PATCH] Show MOD, EAD, END and EADD

[Jan Schubert]

On 01/14/13 16:46, Lutz Vieweg wrote:
> BTW, has anyone ever seen any scientific evidence that for the
> purpose of "avoiding DCS when diving" it is valid to assume that
> the saturation of N2 in the human tissues depends only on the N2
> partial pressure, and is reasonably independent from the partial
> pressure of other gases and the absolute pressure around the body?

Sounds interessting, so keep me updated about your learnings about this
topic :-).
In my understanding it does not matter for tissue saturation limits
(defined by Haldane/Bühlmann/whatsever) if you dive with Nitrox or
Heliox or Trimix, meaning you can saturate and "stress" the tissue with
N2 _and_ He up to the defined values for each single inert gas. Is this
what you mean?


> And if such evidence exists, wouldn't that mean that the same
> assumption / simplification should also be used for de-saturation,
> so the decompression stops should be done at different depths when
> using EAN > 21 than with air?

Desaturation means things goes the other way round, meaning you have
(mainly) to consider the pN2 in your tissues not in the gas breathing.
Having much lower pN2 in the gas breathing helps desaturating faster but
will not allow you to do stops later/more shallow (except you
desaturated enough earlier due to breathing lower pN2).
!?

> The literature I have seen so far makes the first assumption
> (N2 saturation depends only on the pN2) but doesn't make the second
> (decompression stop depths are independent of the pN2, only the length
> of the stops differs according to the accumulated N2 saturation).
>
> Without having dug deeply into the topic, this seems somewhat
> implausible to me.
>
> Regards,
>
> Lutz Vieweg
>
> PS: Has anyone ever been asked to do a "safety stop" at != 5m when
>     diving EAN instead of air? :-)

Whats a safety stop?

Jan