What must passengers do once the supplemental oxygen masks drop?

When supplemental oxygen masks drop, passengers must pull the masks firmly to start the flow of oxygen. This action is crucial because the mechanism that delivers oxygen is typically activated by pulling the mask down. Failing to pull the masks firmly may result in a lack of oxygen flow, which can be vital during emergency situations, particularly when the cabin experiences a drop in pressure.

In flight emergency protocols, passengers are instructed to secure their own masks before assisting others. This priority ensures that they are receiving oxygen and can remain conscious and capable of helping others, should they need to. Therefore, taking the appropriate action to initiate oxygen flow is essential in safeguarding their health and safety during an inflight emergency.