| Many local codes require that exhaust fans installed in fire-rated ceilings must be protected by dampers, which, in case of fire, protect against the spread of heat and flame. Being fire-rated means the ability of a wall, floor/ceiling, or roof/ceiling to withstand the effects of fire for a specified period of time. NuTone ceiling radiation dampers are designed to protect the openings in 1-, 2-, or 3-hour fire-rated floor-ceiling and roof-ceiling designs. When the temperature of the air passing through the damper exceeds 165°F, the fusible link melts and the thermal fabric across the damper closes automatically to interrupt the airflow by becoming a flame and heat barrier, preventing rapid spread of fire to other areas. |
