What is the primary concern of Protective Breathing Equipment when used?

The primary concern of Protective Breathing Equipment (PBE) is to supply oxygen in case of smoke. PBEs are designed to protect crew members and passengers from the harmful effects of smoke inhalation during in-flight emergencies. They provide a breathable air supply that helps maintain a safe environment for individuals in areas where smoke may compromise their ability to breathe effectively. This is critical in situations such as onboard fires or smoke from aircraft systems, as adequate oxygen supply is essential for maintaining consciousness and rational thinking until the situation can be resolved or the aircraft can land safely.

In contexts like turbulence, comfort might be a consideration, but it is not the primary function of PBE. Similarly, assisting in landings and regulating cabin air pressure are more related to aircraft systems and procedures rather than the specific purpose of PBE. Their main focus remains on ensuring that individuals can breathe in the presence of smoke or hazardous conditions, making the provision of supplemental oxygen their essential role.