Fire door set testing is carried out to ensure that the product being produced will do its job of slowing the spread of fire and smoke. Once it is established that a manufacturers specification is meeting the required standardisation, they will then be considered for certification. Once certification is gained, fire doors are then identifiable through stickers found on the door set. When determining the FD rating of fire doors, manufacturers have their fire doors assessed through a testing procedure as specified in BS 476-22:1987 or BS EN 1634-1:2014. Tests are carried out on a complete fire door set: i.e.. the fire door and door frame with all the required ironmongery (e.g. locks, latches, hinges, etc). The door set is fixed in a wall representing its use in within a building. The test procedure consists of exposing one face of the door to the heat conditions anticipated in a fire while observing the door for stability and integrity. The passable standard requires the tests to be carried out with the upper part of the door under a small positive pressure, thus simulating the conditions likely to occur in a fire. It also provides a method of identifying the loss of integrity of a fire door by the implementation of a combustible fibrous pad on the unexposed side of the door to see at what time it ignites. A fire door should be tested from each side to establish its performance with either face exposed to fire conditions, two sets are required. It is predicted that all fire doors and door frames manufactured to the same specification as the two supplied sets, will then achieve the same fire resisting properties.