What cabin pressure altitude allows a pilot to operate without supplemental oxygen for up to 30 minutes?

The correct choice is based on FAA regulations regarding the use of supplemental oxygen in relation to cabin pressure altitude. A cabin altitude of 12,600 feet MSL allows pilots to operate without supplemental oxygen for a duration of up to 30 minutes. This standard is set to ensure passenger and crew safety, as the risk of hypoxia—an oxygen deficiency in the body—begins to increase significantly at higher altitudes.

When cabin altitude exceeds 12,600 feet, the physiological effects of lower oxygen levels in the atmosphere become more pronounced. While a pilot can fly at lower altitudes without supplemental oxygen, the specific altitude of 12,600 feet marks a threshold at which brief exposure is permissible, but caution is still advised to avoid the onset of hypoxia symptoms after that 30-minute period.

In contrast, the other options represent higher altitudes where the requirement for supplemental oxygen becomes more critical. At 14,000 feet MSL, the requirement is that supplemental oxygen must be used continuously for all pilots after that altitude is reached. For 15,000 feet MSL, the use of supplemental oxygen becomes even more crucial for both pilots and passengers, with no time limit provided for safe operation without it. Understanding these altitude regulations helps pilots maintain