How long does the oxygen in a personal breathing equipment (PBE) last?

The oxygen in a personal breathing equipment (PBE) typically lasts approximately 15 minutes. This duration is designed to provide enough time for an individual to escape from a hazardous environment or to perform necessary emergency actions in the event of smoke or fire. The 15-minute supply is a critical safety feature that ensures a person has adequate time to protect themselves and reach safety, allowing them to breathe clean oxygen when other air quality may be compromised. This standard duration is based on the expected need in aviation and emergency scenarios, making it essential that users are familiar with the functionality and limitations of the PBE.