When you run out of oxygen on a mask, instead of setting to zero and not being useful, instead it sets itself to 255. Might also be a factor of putting a zero mask in your hands.
Either way, looks like an underflow error.
When you run out of oxygen on a mask, instead of setting to zero and not being useful, instead it sets itself to 255. Might also be a factor of putting a zero mask in your hands.
Either way, looks like an underflow error.