What is the function of Protective Breathing Equipment (PBE) on an aircraft?

Protective Breathing Equipment (PBE) serves a crucial role in an aircraft's emergency response strategy, specifically focusing on safeguarding crew members. Its primary function is to protect the crew from hazardous fumes, smoke, or other harmful airborne substances that may be present during an incident, particularly in the event of a fire or smoke in the cabin.

The equipment typically consists of a hood that provides a supply of breathable air, allowing the crew to perform necessary duties safely, such as conducting an evacuation or addressing a fire onboard. This protective capability ensures that the crew can maintain their ability to act and communicate effectively despite dangerous conditions, enhancing overall safety.

While the other options involve elements of emergency response or cabin safety, they do not accurately describe the specific purpose of the PBE, which is distinctly focused on protecting crew members from toxic fumes rather than assisting passengers, providing oxygen supply, or maintaining cabin pressure.