Article 81 Use of oxygen - non-commercial air transport flightsI1
United Kingdom
This article applies to any aircraft registered in the Territory that is flying for any purpose other than commercial air transport.
Except where the cabin pressure altitude does not exceed 10,000 feet during the flight, on every flight to which this article applies the pilot-in-command of the aircraft must take all reasonable steps to ensure that—
before the aircraft reaches flight level 130 the method of use of the oxygen provided in the aircraft in compliance with the requirements of article 35 is demonstrated to all passengers;
when flying above flight level 130 all passengers and crew members are instructed to use oxygen;
during any period when the aircraft is flying above flight level 100 up to and including flight level 130 oxygen is used by all the flight crew of the aircraft for any part of the flight between those altitudes that is of more than 30 minutes duration; and
during any period when the aircraft is flying above flight level 130 oxygen is used continuously by all the flight crew of the aircraft.