I agree, it's rare to see a modern reg that is not suitable for nitrox up to 40%. Many companies seem to be using EPDM o-rings now. But even if they do not, nitrile rubber o-rings have been standard in aviation O2 service for decades, and while not ideal, it will be at worst just fuel with a lower ignition temp, not a source of ignition and you need O2, fuel and an ignition source to get a fire.
The only aviation O2 fire related incident that comes to mind is Bob Hoover's first P-51, which burned during a fill of the O2 system - but the culprit there was an overfilled O2 tank that exploded.
The only aviation O2 fire related incident that comes to mind is Bob Hoover's first P-51, which burned during a fill of the O2 system - but the culprit there was an overfilled O2 tank that exploded.
