Assembly buildings are high life risk premises. People often very densely occupy such buildings and they do so in large numbers so they must be given good protection against fire and smoke by the building and by the fire safety management systems in place.
Evacuations from these buildings require careful consideration and management. Voice alarms are usually required as well as effective staff procedures to ensure that the buildings are evacuated quickly and safely. Often, the entertainment that is being provided will cease on actuation of the fire alarm and lighting levels increased. If a stage is being used by performers then it is known that a direct announcement to the crowd by a person on the stage will be very effective at motivating people to evacuate. A recorded voice message is probably not quite so effective but still good.
When inspecting an existing assembly building, the exit widths or staircase widths are not likely to have changed but the seating layout may have done so and this should be checked.