[MisterTea]

> And I think the outer space report was from space walks, and the explanation was that the first time the airlock itself was exposed to hard vacuum, the surfaces of the airlock would have a reaction that left a scent of ozone.

I work with industrial vacuum machinery and the big slow down in a vacuum system is coaxing out water vapor which sticks to chamber and plumbing walls like glue. My guess is dissolved oxygen in the water vapor or the water vapor itself reacting with dust particles.