[Billthedrill]

He means by percentage, and he's correct. It's thinner, to be sure, but it's still roughly 80/20 nitrogen/oxygen. You do have to pressurize it, of course.

[pops88]

He means by percentage, and he's correct. It's thinner, to be sure, but it's still roughly 80/20 nitrogen/oxygen. You do have to pressurize it, of course.

I think distinguishing concentration would be less confusing. Without doing a bunch of look up, from my nursing experience I was taught room air at sea level was 21% oxygen, but in Denver it was closer to 25%. Either way, it seems an ignorant remark coming from someone who claims to be a pilot. Considering what was posted, I find it hard to believe this person is truly a pilot, and not just from the oxygen remarks.