Glazing forms an integral part of a fire door assembly. Incorrectly specified glass can fail very rapidly. Only tested proprietary glazing systems can be used in a fire door, with the appropriate glazing bead, intumescent and fixings. Fanlights and sidelights must also be considered as part of the complete assembly.

It must also be noted that clear fire rated glass must be identified with an etched or sandblasted decal on each pane. This will identify the type of glass and associated fire rating.