These are installed during the HVAC ductwork and so are triggered to shut whenever they sense smoke. Smoke dampers usually are manufactured from aluminum and have a motorized actuator that closes the damper. If you wish to cancel your flight, the equilibrium are going to be credited again for you https://aircontroldampersforengin12344.laowaiblog.com/35560535/air-control-dampers-for-hot-climates-an-overview