They're installed within the HVAC ductwork and they are triggered to shut once they perception smoke. Smoke dampers are frequently made from aluminum and possess a motorized actuator that closes the damper. Smoke dampers kick in when they detect smoke during the air, closing off elements of the ventilation program https://remingtonargvi.madmouseblog.com/17248849/the-smart-trick-of-air-control-dampers-for-engine-sheds-that-no-one-is-discussing