How long does the emergency oxygen cylinder provide oxygen for?

The emergency oxygen cylinder is designed to provide supplemental oxygen for a limited duration in high-altitude situations, typically around 10 minutes. This time frame is crucial for ensuring the safety of passengers and crew by allowing sufficient oxygen during sudden decompression or emergencies, while also providing enough time to descend to a safer altitude where normal breathing can be resumed.

The other options suggest durations that either do not align with the typical operational standards for emergency oxygen systems or imply that the oxygen supply lasts indefinitely. In reality, the cylinders are designed to be used for a set amount of time to ensure effective management of the oxygen resources available in emergency situations.