Testing should be carried out on an entire door assembly, rather than individual components. This is because the testing procedure is meant to check how an actual door installation performs under fire conditions – not just a single door element. So, a door leaf must be tested along with the elements it will be installed with – such as the door frame, any glazing, door closer, door lock and smoke seals etc.
The door assembly is fixed in a wall similar to the one installed on-site. Then, one face of the door will be exposed to a controlled fire conditions that would be expected in a fire situation as per NFPA 252. During the testing, the door will be observed for stability and integrity. Combustible dry cotton will be placed on the unexposed side of the door to see when it ignites.