Why is knowledge of oxygen requirements crucial for pilots?

Knowledge of oxygen requirements is crucial for pilots primarily to ensure safety at high altitudes. As altitude increases, the atmospheric pressure decreases, which results in a lower partial pressure of oxygen available for breathing. At high elevations, especially above 10,000 feet, pilots and passengers may experience hypoxia, a dangerous condition caused by insufficient oxygen. Understanding these requirements allows pilots to make informed decisions regarding the use of supplemental oxygen systems and to monitor their own conditions as well as those of their crew and passengers. This is essential to maintain cognitive function, awareness, and overall safety during flight operations in elevated terrain or cruising altitudes.