Evacuation of atria under different uses

Atria are commonly constructed in building complexes of the Far East, including Hong Kong. Fire safety has become a concern as a consequence of several large fires that have occurred since 1996. Atria are usually designed with an appropriate means of escape, but temporary structures or partitions are sometimes placed on the atrium floor. As a result, the evacuation patterns of occupants are then altered significantly from the original design. Safety aspects of evacuating occupants from the atrium floor were studied by considering two atria in Hong Kong under different uses. Simulations of each atrium were carried out to study the evacuation time with a different number of occupants. The first atrium was used to demonstrate how evacuation time would be prolonged by putting in temporary structures, and, the second was used to illustrate how locations of exits should be designed carefully. The software BuildingEXODUS was selected as the simulator. Results illustrated that emergency exits have to be provided carefully, not just by increasing their number. Safety management should be worked out by controlling the number of people staying in the atrium. A good choice is to apply engineering performance-based design. As most of the evacuation software was developed in the Western world, empirical parameters such as preaction time might not be suitable for the Far East. For giving better safety, studies on emergency evacuation are proposed.