https://www.reuters.com/technology/space/nasa-accidentally-b...
https://www.reuters.com/technology/space/nasa-accidentally-b...
A leak in a pressure vessel is basically how deep saturation divers re-acclimate to standard pressure, and they're making a much, much larger change in pressure (maximum of 14.5 psi delta on the ISS, ~429.06 for a saturation diver at 1000 ft). It's really a delta P of 10 psi though, since the American space suits are 4.5 psi. There's not really much point in talking about decompression sickness without a space suit; they'd die of lack of O2 or exposure even without DCS.
Current recommendations for space walks are a 4 hour denitrogenation period breathing 100% oxygen, and that's pretty cautious. That's based on the denitrogenation rate of the slowest tissues; it could likely be done significantly faster without presenting dramatically increased risks of DCS, and especially so if you only need to avoid type 2 DCS where the bubbles present a risk of dying.
>> Helium is used in the spacecraft’s thruster systems to allow the thrusters to fire without being combustible or toxic.
I'm assuming it's used to backfill tanks as they're emptied?
1) To keep the fuel/oxidizer pressurized and liquid (by pressure) as the tanks content empties.
2) for RCS thrust, as a cold gas thruster.
But where Boeing goes, bad things follow.