"O. Sami Saydjari" wrote in message
...
OK, very helpful answers. But, how does one get a "pressurized mask"?
Is this a matter of buying a pressurized mask and hooking it to a
built-in O2 system (such as might be found on a Cessna Turbo 310), or is
there something special about the 02 system itself that is needed. It
sounds like one needs a special pressure regulator like one might find
in Scuba equipment. I ask this because I want to know what to ask for
when I am looking at Turbo Cessna 310s in terms of an adequate O2 system
to make it up to its 28,000 ft service ceiling.

-Sami

Some information!

http://www.mhoxygen.com/index.phtml?...prd_group_id=4

http://www.aerox.com/Pages/masks.html