[King Moonracer]

Exactly to my point. Space faring vessels probably run at 1 atm. Not at 12,000 or 30,000 feet above sea level.

[Paladin2]

I was a good question. I guessed it was between 0 to 5,000 ft altitude and was surprised that it was all the way to sea level.

Though, as the US sends up volumes likely sealed at sea level so there would be less to accommodate at the ISS airlock if the pressures were approximatly equal.