Two-Hour-Rated, Metal-Stud-and-Gypsum Assembly
Two-Hour-Rated, Spray-Applied, Fire-Resistive Material Assembly
Two-Hour-Rated, Metal-Panel-and-Gypsum Assembly
UL’s testing process involves placing test assemblies in a furnace and exposing one face to fire to determine the fire rating. In the case of glass assemblies (shown here), the fire is evident during the testing process.
In the case of opaque assemblies, the testers must rely more on temperatures collected by thermocouples inside the furnace. After the test fire is extinguished, UL technicians can compile the temperature data, along with information such as roof-deck deformation (shown here) and material failure to help determine the rating (in hours) that each assembly receives.
Column assembly after testing.
