What is the main safety precaution regarding altitude and oxygen use?

The primary safety precaution regarding altitude and oxygen use is the requirement to use supplemental oxygen above certain altitudes. This is critical because as altitude increases, the atmospheric pressure decreases, which reduces the amount of oxygen available to breathe. At higher elevations, particularly above 12,500 feet, the air contains significantly less oxygen, potentially leading to hypoxia, a condition where the body does not get enough oxygen to function properly.

To mitigate the risk of hypoxia and ensure the safety and performance of pilots and passengers, supplemental oxygen is used when flying above specific altitudes. This safety measure helps maintain cognitive and physical functions, preventing dangerous situations that can arise from inadequate oxygen levels. The specific altitude where supplemental oxygen becomes essential can vary depending on regulations and the duration of exposure, but it is a crucial consideration for aviation safety.