How long does it take to put on a PBE during a fire emergency?

In a fire emergency, wearing a Protective Breathing Equipment (PBE) is critical for crew members to ensure their safety while performing necessary tasks. The correct choice of 10 seconds reflects the practical time needed to don a PBE effectively under pressure, such as during a fire.

The 10-second timeframe allows for the necessary steps to securely fit the equipment on the head, ensure the seal is effective to prevent smoke inhalation, and check that all components are functioning properly. This timing is established based on training protocols and industry standards, emphasizing the importance of quick but thorough preparation in emergencies.

While the other options might suggest quicker times, they do not account for the critical need to ensure that the PBE is fitted correctly, which could be compromised if rushed. Safety and effectiveness are paramount in emergency scenarios, making the 10-second mark a practical and safe estimation for this action.