NCO.IDE.A.150 Supplemental oxygen — pressurised aeroplanes

(a) Pressurised aeroplanes operated at flight altitudes for which the oxygen supply is required in accordance with (b) shall be equipped with oxygen storage and dispensing apparatus capable of storing and dispensing the required oxygen supplies.

(b) Pressurised aeroplanes operated above flight altitudes at which the pressure altitude in the passenger compartments is above 10000 ft shall carry enough breathing oxygen to supply:

(1)  all crew members and:

(i)  100 % of the passengers for any period when the cabin pressure altitude exceeds 15000 ft, but in no case less than 10 minutes’ supply;

(ii)  at least 30 % of the passengers, for any period when, in the event of loss of pressurisation and taking into account the circumstances of the flight, the pressure altitude in the passenger compartment will be between 14000 ft and 15000 ft; and

(iii)  at least 10 % of the passengers for any period in excess of 30 minutes when the pressure altitude in the passenger compartment will be between 10000 ft and 14000 ft;

 and

(2)  all the occupants of the passenger compartment for no less than 10 minutes, in the case of aeroplanes operated at pressure altitudes above 25000 ft, or operated below that altitude but under conditions that will not allow them to descend safely to a pressure altitude of 13000 ft within 4 minutes.

(c) Pressurised aeroplanes operated at flight altitudes above 25000 ft shall, in addition, be equipped with a device to provide a warning indication to the flight crew of any loss of pressurisation.