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13 days agoPartial pressure of the gases you breathe is what matters though
Just to clarify, the partial pressure of oxygen in the atmosphere is about 3 PSI. The partial pressure of Nitrogen in the atmosphere is about 10 PSI.
that’s why astronauts could breathe pure oxygen for days during the Mercury/Gemini/Apollo missions and be fine (as long as there’s no fire :/ ).
Fire risk is also related to the partial pressure of the gas. 100% oxygen is not actually a problem, so long as the partial pressure of that oxygen is low. The partial pressure of oxygen in the Apollo 1 capsule was about 16.7 PSI.
Astronauts still use 100% oxygen in space suits pressurized to about 5PSI.
No. They have to vent if your household pressure is too high. If, for example, cold gas was admitted into your lines, and that gas heated up, the pressure in your lines would increase. The regulator can’t push that gas back into the high pressure main, so the regulator would have to bleed off the excess pressure.