Fire-Rated Doors

FIRE-RATED DOORS are typically doors opening on to rated corridors or stair wells or through occupancy or area separation walls. Such doors are there to preserve the integrity of the fire rated walls they penetrate, and usually stay closed or are held open by either a "fusible link", an element that burns through and allows the door to close in a fire, or a magnetic hold-open whose release is activated by the building's fire alarm or sprinkler system.