What is the maximum cabin pressure altitude at which a pilot can fly for longer than 30 minutes without using supplemental oxygen?

The maximum cabin pressure altitude at which a pilot can operate without the use of supplemental oxygen for flights longer than 30 minutes is 12,500 feet. Above this altitude, it becomes increasingly difficult for the body to obtain enough oxygen due to the reduced atmospheric pressure, leading to potential hypoxia. The regulations set forth by aviation authorities are designed to ensure pilot safety and mitigate the risks associated with altitude.

While pilots can maintain flight up to 12,500 feet without supplemental oxygen for an extended duration, once the altitude exceeds this limit, the regulations require the use of supplemental oxygen. This is to avoid the risks of oxygen deprivation that can impact cognitive and physical performance, which are critical for safe flight operations. The option that states 12,500 feet accurately reflects this regulation.