Standard Room Fire Test Development at the National Bureau of Standards

Abstract

Research results with the proposed ASTM standard room fire test for interior finish materials are presented. The materials selected for the study were two untreated plywoods, a fire-retarded plywood, polystyrene, polyisocyanurate, and gypsum board. Three 900-s duration test scenarios were considered. Scenario A is a constant nominal 160-kW ignition source exposure. Scenario B achieves the same maximum exposure after three intervals of 30 s each in which the heat release rate is increased in equal steps of 40 kW. Scenario C evaluates a material over a 300-s exposure at a nominal 40 kW, with another 300-s exposure at a nominal 160 kW, followed by 300 s at zero exposure. This zero exposure allows the material to be screened for self-burning properties afterwards. The study demonstrated that all three scenarios could adequately differentiate material fire behavior, in terms of the maximum degree of fire buildup attained and the time to reach the maximum, for the materials selected. However, Scenario C would allow a more comprehensive evaluation of materials. Thermal radiation incident on the floor and doorway air temperature were found to be the most consistent parameters for determining room fire buildup including room flashover. Surface flame spread and rate of heat release are discussed for the room fires.