Here is my 100% Guide for Deliver Us The Moon!
This is at the start of Chapter 2 (Pearson Space Station).
For the first time, you will see your oxygen depleting with around 3:00 minutes of oxygen left.
You have to grab a canister from the right hand side, put it into a slot and the door will open.;
Now 3:00 may not seem a lot but it is plenty of time, so you can either go ahead and place the canisters where they are meant to be placed (Either side of the computer monitor in the centre of the room), or just go to the room with a lot of oxygen canisters which is to the right of the central console monitor. (It is obvious when you see it)
Simply wait until the timer gets down to around 1 or 2 seconds and hit
to give yourself some breathing space.
Go to 26:30 in the video to see how and where to unlock this.
Hope This Helps!