1.1 These requirements cover the design and construction of ²tin-clad² fire doors which have
demonstrated in fire tests, fire performance properties sufficient to warrant their use in closure assemblies
having a fire-protection rating of up to and including 3 h, when tested in accordance with CAN/ULC-S104,
Standard Method for Fire Tests of Door Assemblies.
1.2 A door conforming to these specifications consists essentially of a core made up of layers of boards
nailed to each other, encased in terne or zinc plates jointed together at their edges and nailed through the
seams to the core.
1.3 The sizes and ratings for three-ply and two-ply doors, constructed in accordance with these
specifications, are given in Table 1. These ratings are designed to enable regulatory bodies to determine
the suitability of the door assemblies described in this Standard for use in locations where a fire resistance
of a specified duration is required. Requirements for the details of the installation of ²tin-clad² fire doors,
including the requirements for vent holes, are included in NFPA 80, Standard for Fire Doors and Other
Opening Protectives.
1.4 Table 1 pertains only to the maximum size of the opening. Doors limited in size by this table fall into
two categories:
A Swinging doors intended to be installed within an opening; and
B All sliding doors and those swinging doors intended for surface mounting outside of the
opening.
Swinging doors in the first category are limited in size to the maximum dimensions specified for the
opening. Doors in the second category must be larger than the maximum opening dimensions to provide
the minimum 100 mm lap at each side and at the top of the door as required by NFPA 80, Standard for
Fire Doors and Other Opening Protectives.