UL 1256:2018 PDF Download

The UL 1256:2018 standard provides requirements for fire test methods used to evaluate the performance of metallic and nonmetallic roof deck constructions when exposed to internal fire exposures. The purpose of these tests is to determine the contribution of the roof covering material, insulation, and other components to the spread of fire within a building. It is important to note that these requirements are not intended to describe or define the fire hazard or risk of fire under actual fire conditions.

This standard does not include tests to evaluate other potential hazards to roof deck constructions, such as structural integrity under fire exposure or wind uplift. Instead, it focuses specifically on the fire performance of the roof deck constructions. The standard describes two fire test methods, referred to as Part i and Part ii. The selection of the appropriate test method is based on an assessment of fire test experience.

Part i describes a large-scale fire test method used for roof deck constructions that have been known to contribute extensively to underdeck fire spread or are eligible for classification based on experience. Part ii describes a small-scale fire test method using the Steiner fire test chamber. Conditions of acceptance for this test method were initially established by analyzing data from a specific construction that exhibited adequate performance in the large-scale test method described in Part i.

For roof deck constructions that are dissimilar to any previously evaluated under Part i, the large-scale fire test method is to be conducted. The standard provides specific guidance on the test methods and conditions of acceptance for evaluating the fire performance of different types of roof deck constructions.