Its used in commercial diving. He02 surface gas diving or Saturation Diving. We used to go through thousands of dollars a day of gas on open circuit. Now most Saturation Diving systems us a gas reclaim system where the exhaled gas is scrubbed of CO2 replinished with 02 and sent back to the diver.
You dudes are wound waaay too tight.
I make a light hearted comment linking helium and munchkins and the “wrapped too tight” crowd takes it seriously. Obviously, you cannot grasp levity.
Lighten up, Francois!