A fire damper is a normally closed valve that can be opened by 24V DC power from the control center or manually. It closes automatically at 280℃ and must be manually reset. Its function is to automatically close the valve when the smoke temperature reaches 280℃, as at this point, the evacuation is mostly complete and smoke extraction is no longer practical. Since the smoke now carries fire, the automatic closure of the valve prevents the spread of the fire. The exhaust air outlets in the system can also be equipped with normally closed fire and smoke exhaust outlets, eliminating the need for fire damper valves on branches. During a fire, the outlets are opened by 24V DC power from the control center or manually, and they automatically close when the smoke temperature reaches 280℃, requiring manual reset. A smoke and fire damper should also be installed at the entrance of the exhaust fan room to prevent the fire from spreading to the floor where the fan room is located.