NFPA 80, NFPA 105, and NFPA 252 details fire rated doors and their inspections. The doors we inspect have two (2) criteria, fusible links and magnetic holds. 

 

Fusible Link Door include various types of doors. Doors that have vertical or horizontal movement of operation  are either held open by a chain attached to a fusible link or the release (fire) spring is maintained open by the chain and fuse link. Normal operation of these doors are open and close but regardless of the doors position if the fusible link is heated past it’s rated temperature the door will shut and remain closed till the spring is rewound and the latching mechanism is reset.

 

Some examples are: Pharmacy windows, billing reception desk, kitchen scullery, jail and military armories. Most of these windows have a roll-up door overtop of them that in normal operation can be pulled down and locked as a security door. 

 

Other examples are garage doors with manual or motor driving openers. These doors could be throughout the building and not just at the loading dock. Garage doors separate rooms housing chemicals, paint, explosive or combustible material, warehouse stock, or even boiler rooms from the main building.