Hey, so this is my quick closed system I use for airlocks. I'm in Creative but the method is pretty much the same for Survival of course. In this video I'll show you how to set one up, some pitfalls that can occur, and how to make your doors auto-close without a script - as well as turn a light on/off based on the airlock state.
Note: A closed system will transfer o2 from the tank to the room and back, once the tank is around 50% full I suggest turning off the generators and then you can swap the air from room to tank, with no loss if you don't vent the room to space.
SD Unity Skybox: https://spaceengineers.mod.io/sixdice... uploaded by FlareUK & SixDice
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