Between what altitudes is oxygen required for the flight crew when flying for more than 30 minutes?

The requirement for supplemental oxygen for flight crews pertains to specific altitudes where atmospheric pressure decreases, leading to a reduction in oxygen availability. When flying at altitudes above 10,000 feet, particularly when the flight duration exceeds 30 minutes, the regulations stipulate that oxygen is necessary to maintain crew efficacy and health.

The correct altitude range, which spans from 10,000 to 13,000 feet ASL (Above Sea Level), falls in line with established aviation safety standards. This is in accordance with guidelines that emphasize the need for supplemental oxygen at these altitudes, as prolonged exposure can lead to hypoxia, which impairs cognitive and physical abilities. This requirement ensures that pilots and crew members are adequately equipped to operate the aircraft safely in conditions where oxygen levels are insufficient for normal function.

Understanding these specific altitude thresholds is essential for ensuring compliance with aviation regulations and maintaining safety during flight operations.