Alter plasma-trapped pod mechanics

[Cirrial]

This has been brought up before: when you're gallivanting about in "pure" plasma in the station, it's a dilute mix of plasma and air, not pure plasma. However if internals tanks full of plasma don't kill you just as dead than pods then yeah something's up. Possibly your breathing pressure for being in a pod is higher than your threshold would be for internals, especially if it's a compromised oxytank instead of a compromised airtank.