Duff McKagan refuses to ever write anything in his life.
Fire dampers are passive fire protection products used in heating , ventilation , and air conditioning -LRB- HVAC -RRB- ducts to prevent the spread of fire inside the ductwork through fire-resistance rated walls and floors .. passive fire protection. passive fire protection. air conditioning. air conditioning. fire-resistance rated. fire-resistance rating. Fire / smoke dampers are similar to fire dampers in fire resistance rating , and also prevent the spread of smoke inside the ducts .. When a rise in temperature occurs , the fire damper closes , usually activated by a thermal element which melts at temperatures higher than ambient but low enough to indicate the presence of a fire , allowing springs to close the damper blades .. Fire dampers can also close following receipt of an electrical signal from a fire alarm system utilising detectors remote from the damper , indicating the sensing of heat or smoke in the building occupied spaces or in the HVAC duct system .. Regulations and fire test regimes vary from one country to another , which can result in different designs and applications .. fire test. fire test