How far can man travel into the atmosphere before he can't breathe?

Answer 1

If you think about it, you can understand that the amount of oxygen in the air becomes less as your altitude increases. With each breath, you get less O2 to keep you conscious and alive. And as you consider this, you can probably figure out that altitude affects people differently. There is what is called a threshold for the medical condition called altitude sickness (acute mountain sickness) that begins at about 8,000 feet, or about 2,400 meters. Blood chemistry changes in response to decreasing air pressure as we gain altitude. The process is a bit involved, it's complex, and it takes a bit of study. And it's not all about just the oxygen. It's the law of partial pressures of gases and (more importantly) the pathophysiological response. The bottom line here is that different individuals are affected differently by increases in altitude. Some are more susceptible to the negative affects of those changes in altitude than others. Peoples that live at altitude actually have "different" blood to cope with the reduced oxygen higher up. And that's just one example of differences between people. Some adventurers have actually climbed Mount Everest (29,000+ feet) without supplemental oxygen, but they are rare birds, and risk their lives to do that. We may have confused you, though it was not the intent. Consider that Andean peoples have lived at high altitudes for thousands of years and think nothing of it. Visitors to the natives at those altitudes might experience light headedness or dizziness. Loss of breath is possible, as are headaches, tingling in the limbs and swelling (edema). And the list goes on. But you're getting the picture. Use the link below to review what we call altitude sickness. That's about the best we can do. Feel free to return after your research and post more. Links can be found below.

Answer 2

You can breathe as long as there is a gas to inhale (about 100 miles) - you wont get enough oxygen to survive however. But the accepted height where you need external oxygen supply is above 14,000'.

Answer 3

Depends on the person, but you could still breath at 15-20 thousand feet with some difficulty. Staying at that altitude/elevation for a period of time would result in a variety of health issue. Above these altitudes - maybe 25 thousand feet and up - there's a sufficiently low level of oxygen in the air that you would run into some fairly severe physiological consequences. If you're talking about being immediately exposed to such an elevation with no equipment, I suspect that that would be fatal unless you could return to the surface pretty quickly.

Answer 4

People have gone to the top of Everest without oxygen. So... about 30,000 ft.

Answer 5

You would probably notice that you tire easily, and don't sleep as well,

once you get past 3 miles up for any length of time.

Answer 6

maybee just a little high

Answer 7

because you cant there no trees

Answer 8

20,000 feet