Can the Na'vi breathe an Earthlike atmosphere?

[Clarke]

Originally Posted by Human No More

Wrong.
Pressure is not necessarily higher, you're thinking of density. Vehicles and buildings are pressurised above ambient so in case of minor damage, atmosphere leaks out and not in. Pandora's atmospheric pressure is actually 0.9atm, so presumably the vehicles and buildings are ~1.0 or more.

H2S is not toxic on skin contact except as a liquid. He would have had some eye irritation, as well as to mucous membranes of nose/throat, but it is perfectly possible not to actually inhale it.

I was under the impression that H2S was a vapour, when it is actually a gas, just, at STP. That does save Quaritch some pain, but the fact that vehicles might be pressurized doesn't, since he walks straight out of the building into the open air at one point.

However, I think you are downplaying how much damage it'll do; the WW1 era British Army commented that H2S was "not an ideal war gas," at 1/10th the concentration it's apparently has in the atmosphere. Even small amounts of it in his eyes or windpipe would cause severe damage.

[Human No More]

How could the building not be pressurised? He kicks open a door, which doesn't have an airlock on it so I would guess is some kind of emergency exit. That's a BIG hole, so the internal pressure is lost all at once, as opposed to slowly when there is minor damage.

Chemical warfare in a context such as WW1 was ideally to injure rather than kill since then the enemy would be forced to spend more resources.

[Cyvaris]

AND THEY ARE OFF!!! Place your bets now people! Who will win this scientific show down!!


Actually one thing to consider apart from earth's air is the gravity. For humans the lighter gravity of Pandora doesn't seem to bad, but the Na'vi may have a problem on earth. Depending on sciencey things I have no idea about the lower gravity could in theory cause their lungs to "collapse". The lighter atmosphere on earth would also be a problem.

Also, Earth's atmosphere is pretty much trashed by the time Avatar takes place. Sure human's can tolerate the smog (we adapted!) but to the Na'vi all those pollutants would be very deadly.

[Human No More]

Not at +0.2G. Humans are fine exposed to a lot more than that via centrifuge.

The issue of Earth in the Avatar universe is a point worth considering though, but that's more of an issue than Earthlike general composition e.g. indoors at Hell's Gate.