Fire doors may be made of a combination of materials, such as:
Gypsum (as an endothermic fill)
Both the door leaf (the swinging panel of the door) and the door frame are required to meet the guidelines of the testing agency which provides the product listing. The door frame includes the fire or smoke seals, door hardware, and the structure that holds the fire door assembly in place. Together, these components form an assembly, typically called a "doorset" which holds a numerical rating, quantified in hours of resistance to a test fire. All of the components of the fire door assembly must bear a listing agencies label (with the exception of ball-bearing hinges which meet the basic build requirements of ANSI 156.2 and NFPA 80) to ensure the components have been tested to meet the fire rating requirements.