An oxygen mask is the mask that drops if cabin air pressure fails. Pull down the oxygen mask.
The supply lasts around twelve minutes, which is all the time the aircraft needs to descend. An oxygen mask on an airliner is fed by a chemical reaction rather than a tank.
1nounoxygen maskThe mask that drops if cabin air pressure fails.
“The oxygen mask dropped over one row and nowhere else.”
oxygen mask is equipment.
Practised in Airport & Flying