To qualify for UL listing as "acceptable," a roof deck assembly
when subjected to a UL 1256, Fire Test of Roof Deck
Constructions, flamespread test must not spread the flame farther
than this standard steel-deck assembly.
Temperature. A roof assembly's time-temperature rating
(given in time units of hours and fractions of hours) is
established by its performance when subjected to the furnace test
as specified in ASTM E 119, Fire Tests of Building Construction
and Materials. The test subjects the tested assembly to a
constantly rising temperature.
Fire-endurance Test. This test measures roof assembly
performance when simultaneously carrying loads and confining
fire. To qualify for a given fire rating, the tested assembly
must: sustain the applied design load, permit no passage of
flame or gases hot enough to ignite cotton waste on the unexposed
surface, and limit the average temperature rise of the unexposed
surface to a maximum 250 degrees F (121 degrees C) above its
initial temperature or a 325 degrees F rise at any point.
Other Tests. For steel assemblies with structural
steel, prestressed, or reinforced concrete beams spaced more than
4 feet (1219 millimeters) on centers, there are several other
complex requirements specified in UL 263, Fire Tests of Building
Construction and Materials.
Design Requirements. Follow MIL-HDBK-1008 Section
entitled "Roof Coverings and Roof Deck Assemblies."