"Stefan" wrote in message
...
fred wrote:

The question was what happens when breathing air from the mask rather
than O2 and the answer is nothing at all at a cabin pressure of 10K feet.

Got me :-). On the other hand, if the bottels were filled with say N2
instead of O2, they would still have faded away even at 10 kft. Further
speculations?

Yes and pure N2 is faster than air at 35,000.