"Eric Greenwell" wrote in message
...
Bill Daniels wrote:


At 16,000 ft., I can't tell the difference with or without O2.


Unfortunately, feeling fine can be one of the first symptoms of hypoxia.
How you FEEL means little. The only quantitative measure of hypoxia is
a
pulse oxymeter. Borrow one the next time you fly. The numbers will
likely
surprise you.

Since he feels (or at least "can't tell the difference") the same with
and without oxygen, are you suggesting he was hypoxic without the oxygen
but just couldn't tell that he was functioning differently than with the
oxygen?

Exactly.

I often do a similar test when flying with oxygen: I go to 100% for a
couple of minutes; if I then still feel the same and my decisions still
seem sensible, I assume I've been getting enough oxygen.

Does seem like an adequate test for altitudes up to 25,000', the highest
I've gone? I've not used an oximeter, so I don't know what my readings
are before or after.
--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

As one AME put it to me, "If you are self-diagnosing hypoxia without a pulse
oxymeter, you have a fool for a doctor".

I think this is one of the central danger points of aviation oxygen use.
The presumption that a pilot who has a lot on his plate can self-diagnose
hypoxia symptoms has been in use since before WWII with dubious results to
say the least. Inexpensive pulse oxymeters have finally brought some
objectivity to oxygen use. I highly recommend them.

This is especially true with inconsistent oxygen delivery systems like nasal
cannulas.

Bill Daniels