to simulate changing the altitude I hooked a vaccume cleaner up to a big old aluminium tank and then went inside.
I have found that a house hold vaccume cleaner only produces the the equivalent of a thousand feet of elevation.
sorry its so dark inside I plan on fixing it up eventualy, this is just some peliminary experiments.
By the way I do have an confined space operating permit, and there are more safety feachers than are shown in the video.
