Did you see the size of the O2 tanks? 3L 100 bar, maybe is an error.
Personally I don't understand why to hide this project for so long anything special? I've got the idea about a CO2 detector or something like that.
Maybe on the leaflets there aren't the complete description...
Such a mistery...
Nad
O2-tank should be filled to 140bar. When it's time to refill the O2-tank you shall also change the scrubber.