Title: Describe oxygen requirements.
Course: Aircraft Pilot Training I (20053-I) > Section: Exploring Regulations

Description should include the following:

- Unpressurized aircraft—Each pilot of an unpressurized aircraft shall use oxygen continuously when flying
  - at altitudes above 10,000 feet through 12,000 feet mean sea level (MSL) for that part of the flight at those altitudes that is of more than 30 minutes duration
  - above 12,000 feet MSL.

- Pressurized aircraft—Pilots should comply with the following:
  - When a pressurized aircraft is operated with the cabin pressure altitude more than 10,000 feet MSL
  - When a pressurized aircraft is operated at altitudes above 25,000 feet through 35,000 feet MSL, unless each pilot has an approved quick-donning type oxygen mask
  - At least one pilot at the controls shall wear, secured and sealed, an oxygen mask that either supplies oxygen at all times or automatically supplies oxygen whenever the cabin pressure altitude exceeds 12,000 feet MSL.

- Refer to Sec. 135.89, Pilot Requirements: Use of Oxygen, for more information.

PLT438