When is a Building FLS Evacuation Supervisor required to be on duty in a Class B office building?

In the context of a Class B office building, the requirement for a Building Fire Life Safety (FLS) Evacuation Supervisor to be on duty is primarily based on the presence of occupants in the building. This is crucial for ensuring the safety and well-being of all individuals during an emergency situation, as the Evacuation Supervisor plays a vital role in effectively managing evacuations and overseeing safety protocols.

Having an Evacuation Supervisor on duty when occupants are present allows for immediate response to any emergencies that may arise, guiding individuals to safety and coordinating with emergency services. This role becomes particularly important in maintaining order and ensuring that safety measures are followed.

The other options, while they may touch upon considerations for safety in various scenarios, do not encapsulate the fundamental principle that the Evacuation Supervisor's presence is essential whenever there are occupants in the building, as their primary responsibility is to safeguard these individuals during emergencies.