Above what altitude is supplemental oxygen essential for pilots for more than 30 minutes?

Supplemental oxygen is essential for pilots operating above a specified altitude to prevent hypoxia, which is the deficiency of oxygen in the body. The regulation indicates that for flight durations exceeding 30 minutes, supplemental oxygen becomes necessary starting at 12,500 feet Mean Sea Level (MSL) up to and including 14,000 feet MSL. At these altitudes, the partial pressure of oxygen decreases, which can lead to impaired cognitive and physical performance.

The physiological effects of altitude begin to manifest significantly in this range, making supplemental oxygen critical for sustained operation. Pilots and crew members need to be aware of these altitudes to maintain safety and performance levels in the cockpit, reinforcing the importance of using supplemental oxygen during flights in this altitude band.