Supplemental Oxygen Use

Supplemental Oxygen: Key Regulations and Usage

Supplemental oxygen is required in aviation to protect occupants from hypoxia when cabin altitude exceeds safe thresholds. For unpressurised aircraft, oxygen must be supplied to all crew above 10,000 ft, and to all occupants above 13,000 ft. In pressurised aircraft, oxygen masks and systems are mandatory for use by crew and passengers if cabin pressure is lost or when operating above regulatory altitude limits.

Oxygen Requirements by Altitude

• Above 10,000 ft: Crew must use oxygen continuously; if above this altitude for more than 30 minutes, some passengers may also require oxygen.
• Above 13,000 ft: All occupants must have access to supplemental oxygen for the entire duration.
• Above 15,000 ft: Oxygen must be available for everyone on board at all times.

Crew Protective Breathing Equipment (PBE)

Flight crew must have access to PBE, such as smoke hoods, to protect against smoke and fumes, distinct from supplemental oxygen used for decompression or high altitude.

Emergency and First-Aid Oxygen

Aircraft must carry emergency medical kits and first-aid oxygen for passengers who may require it for medical reasons, separate from the oxygen supply intended for decompression events.

Actions During Decompression

• Rapid/Explosive Decompression: Crew don oxygen masks immediately, initiate an emergency descent below 10,000 ft, and secure the cabin.
• Slow Decompression: Crew monitor cabin altitude and oxygen use, and take corrective action before hypoxia symptoms develop.

Detection and Causes of Decompression

Decompression can result from structural failure, window or door seal problems, or system malfunctions. Rapid decompression is often accompanied by noise, fog, or temperature changes, while slow decompression may be detected only by instruments or subtle physiological symptoms.

Oxygen Use in Practice

Proper oxygen mask use and understanding regulatory requirements are crucial for safe operations, especially at high altitudes or following depressurisation.