On Mon, 15 Aug 2005 04:21:32 UTC, wrote:

: Yet, I was once told by an ATP that at 40k feet (admittedly
: this plane was at 35k) O2 supply by itself will not suffice to keep you
: conscious...

Oxygen is only part of it. The breathing reflex is triggered by the
carbon dioxide partial pressure in your lungs: when atmospheric
pressure falls below that you never get the trigger and your lungs
just stop working. This is a Bad Thing.


Ian


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