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>
> To those physiology gurus out there,
>
> I have been pondering this question for a while now.  Please consider this
> scenario:
>
> You're on a deep dive in cold water.  You're wearing your drysuit with
> normal drysuit underwear.  When you have incurred a significant
> decompression obligation, you accidently rip your suit on a jagged piece
> of metal, and it floods.  You immediately abort the dive, but still must
> do your decompression.  On the deco line you start to become very cold,
> and due to the cold, your off-gassing efficiency is significantly reduced.
>
> Now the question.  How can you tell the point at which off-gassing
> efficiency on the deco line falls below the off-gassing efficiency
> that would exist if you were in the dry, warm cabin on the boat breathing
> 100% O2?  Can you tell?  Is there a mathematical temperature model
> that would tie into whatever deco algorithm you're using that you
> could use to determine this (or the optimal deco profile under
> your circumstances)?  I suppose that this is a highly individualistic
> thing, but perhaps generalizations could be made?
>
> Christina

Hi Christina,
I don't know the answer to this one, but I do know that surface compression
oxygen decompression (surD O2) uses much the same deco but omitts the
3 and 6 metre in water stop, then has a stop at some greater depth (usually
12 metres) on pure O2 in the chamber.  The maximum time from leaving the
last in water stop to arriving at the chamber bottom in 7 minutes in the
DCIEM table.  Perhaps if you were going to die of hypothermia you could
try ommiting your 6+3 and grabing a new suit, and going back down on O2
to as deep as you were game.  But you would want to be dying before you
tried a stunt like that.  Perhaps wearing a wet suit under your dry might
not be a bad idea?

Cheers Jason :)

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