Damper is a part of AHU which when adjusted with intake flow of air allows AHU to take a fixed amount of fresh air in the AHU and clean room, maintaining the environmental freshness and oxygen level in the clean room.
In the event of any fire, when AHU remains working the fresh air keeps on flowing inside the room and fire may get out of control. Therefore inorder to keep the fire within control AHU are required to be put off so that oxygen supply is cut off and fire is controlled. This is also done with automatic Fire damper which gets closed with external thermal sensors mounted in a clean room which upon sensing the fire gets closed automatically with motorised closing Valve and stops fresh air supply thereby preventing the spread of fire.
These dampers may also be equipped with a thermal breaker which upon sensing high temperature melts down and closes damper doors of the AHU with spring action.
This safety equipment is required in a manufacturing area where flammable or combustible material is handled.
In Inorder to make the facility fire proof, AHU ducts supplying air to the clean room are covered with fire rated nitrile rubber sheets. Even the panels of the facility can be designed with fire resistant panels.