At what altitude do oxygen masks automatically deploy?

Oxygen masks automatically deploy at an altitude of 14,000 feet due to the potential for cabin depressurization which can severely affect passengers and crew. At this altitude, the ambient air pressure decreases to a level where there is insufficient oxygen for normal respiration. The deployment of oxygen masks provides immediate supplemental oxygen to ensure that everyone on board can breathe comfortably and safely until the aircraft can descend to a safer altitude where the air pressure and oxygen levels are adequate.

The specified altitude of 14,000 feet is based on regulatory safety standards in aviation, which aim to protect individuals from hypoxia, a condition caused by a deficiency of oxygen in the body. This altitude is a critical threshold, and the activation of the oxygen masks is an essential safety feature in modern aircraft design.