Bones Ep. where B&B get Locked in a Room Without Air

[takemetotheclouds]

So in this Bones episode, there is a scene where Brennan and Booth get locked in a room- rectangular shaped, I believe, and it doesn't have much air in it. They are gasping for air, and Brennan tells Booth to breath in a certain way to give them more time before they pass out. 

Eventually, Booth shoots the lock (I think) and they get out.

 

I am trying to find the episode when this occurred. Thank you so much for your help!

[Ava]

I'm not positive, but I think this is "The Science in the Physicist". Season 4, Episode 18.