When should oxygen masks be deployed?

Oxygen masks should be deployed when cabin pressure drops or air quality is compromised because these situations can result in hypoxia, a condition where the body or a region of the body is deprived of adequate oxygen supply. The deployment of oxygen masks in response to a drop in cabin pressure is crucial as it ensures that passengers and crew can breathe safely when the usual ambient air pressure is insufficient to provide enough oxygen.

In scenarios where the cabin pressure drops, such as in the event of an emergency depressurization, the oxygen masks provide supplemental oxygen to help maintain proper oxygen levels in the body until the aircraft can safely descend to a lower altitude where breathable air is available.

Deploying oxygen masks during passenger emergencies, at the start of every flight, or strictly upon passenger request does not adequately address the critical nature of the situations that warrant their use. Instead, their deployment should be based on specific environmental conditions that jeopardize safety, thereby prioritizing the well-being of those onboard.