Final answer:
Pilots must wear oxygen masks at high altitudes or in poorly pressurized aircraft cabins to prevent hypoxia, as oxygen pressure decreases making it difficult for Hb to bind oxygen. The body compensates for lower oxygen levels at high altitudes, but supplemental oxygen is vital for pilot safety and effective functioning.
Step-by-step explanation:
When Does a Pilot Need to Wear an Oxygen Mask?
The use of oxygen masks by pilots is primarily for safety and ensuring proper oxygenation at high altitudes. According to Federal Aviation Administration (FAA) regulations, airline pilots must use an oxygen mask if they are flying at altitudes above 10,000 feet without pressurization, and always above 35,000 feet, even with pressurization. This is because as the airplane ascends, the ambient oxygen pressure drops, making it harder for hemoglobin (Hb) to bind to oxygen, and potentially leading to hypoxia. The body compensates by adjusting levels of 2,3-diphosphoglycerate (DPG) to enhance oxygen release at the tissues. Giving pilots 100 percent oxygen ensures they can function effectively even under decreased ambient oxygen conditions, which is not achievable with carbon dioxide administration. Additionally, with concerns over safety and workplace accidents, regulatory bodies enforce strict limits on operational hours for pilots to prevent fatigue.