At what cabin altitude does the USAF require supplemental oxygen due to low PO2?

The requirement for supplemental oxygen in the USAF is established to ensure the safety and physiological integrity of personnel during flight under reduced atmospheric pressure conditions. At a cabin altitude of 10,000 feet, the partial pressure of oxygen (PO2) decreases significantly, leading to the potential onset of hypoxia in some individuals. Hypoxia is a condition where the body does not receive enough oxygen, and its symptoms can impair cognitive and physical performance.

This threshold of 10,000 feet is particularly critical because while some individuals may tolerate this altitude without supplemental oxygen, it poses a risk for others, especially during prolonged exposure. Therefore, the USAF mandates the use of supplemental oxygen at this altitude to maintain safety and operational effectiveness during flight operations.

Above this altitude, as in options relating to 12,000 and 15,000 feet, further regulations stipulate different oxygen requirements, but the pivotal point for the USAF begins at 10,000 feet. This guideline is designed to enhance crew performance and ensure mission success in the diverse environments faced during operations.