Intermediate-Scale Free-Standing Box Tests for Fire Performance of Sandwich Panels

With regard to reaction-to-fire tests for building materials in Japan, ISO 5660-1 (small-scale test cone calorimeter) is de facto the only method for evaluation, according to the current building standard law of Japan [1], which actually also designates ISO/ TS 17431 (intermediate-scale test) as analternative not being implemented very often, however, bythe industry. It is noted that it is impossible to predict the fire performance of sandwich panels when they are actually used in real buildings only from small scale tests such as ISO 5660-1. This is not a deficiency regarding the ISO 5660-1 as a test method but it is difficult to use the small scale results on a horizontal surface (100 mm by 100 mm) in order to predict the fire performance of sandwich panels in real applications.. The reason is that in actual building fires, both ceilings and walls made of sandwich panels are heated from various directions and weak points are the joints and seals which can never be evaluated with a small-scale test. Therefore, in this study, the authors firstly modified ISO/TS 17431 model box test with free-standing specimens, referring to ISO 13784-1, and different types of sandwich panels were chosen to be the specimens, and the results are discussed comparing with ISO 5660-1 results. K e y wo r d s : Sandwich panel , intermediate-scale box test , free-standing, reaction-to-fire, ISO/TS 17431.