hi all:
well if you are looking at adding anything to do with O2,start by get the alt right.
for startes, you don't need O2 untill you reach about 17000ft, at that alt you are good with out O2 for about 5 mins, that is when your finger tips and lips will start to turn blue, for you smokers out there, about 3 mins is all you have. now once this all starts to happen, you can bet your awearness of what is going on around you will be reduced. now i dont know how the time factor will change as you go higher up in alt, but i do know from experance that 17000ft above sea level is when you have to start to worry about your O2 level. and for those that want to know what experance i have at 17000ft ASL is, well i used to skydive and have made two jumps from that alt, and those where two of the scariest jumps i have mad, not knowing really what the efects would do to me when it came time to open. but as i am sitting here writing this, it must have worked out ok. but you are ok up to about 17000ft before you need O2. and i am a smoker so the non smokers had a great time watching us smokers turnning blue before they did. i have a video of the second jump around here some place, not sure where it is anymore, kinda forgot about it till reading this post, have to see if i can find it.
well i hope this helps a little bit.
wolf37
C.O.
THUNDER BIRDS