THE EFFECTIVENESS OF COATINGS ON THE FLAME SPREAD BEHAVIOR OF ELECTRIC CABLES

摘要

The effectiveness of coatings on the flame spread behavior of electric cables with six differentrninsulation/jacketing materials was assessed using the ASTM E-2058/ISO 12136 Fire PropagationrnApparatus (FPA). Two types of coatings (an intumescent coating and an ablative coating) werernseparately applied to each of the six cable types. The coated cables as well as uncoated cables werernsubjected to piloted ignition tests and vertical fire propagation tests in the FPA. The results from theserntests were used to derive a fire propagation index (FPI) for each sample. The FPI was taken as thernratio of one-third power of the maximum chemical heat release rate per unit circumference of therncoated or uncoated cable to the ignition resistance expressed as a thermal response parameter (TRP).rnThis index has previously been correlated to the extent of flame propagation of electric cables inrnintermediate-scale parallel panel tests using a 60 kW sand burner as an ignition source. Time tornignition, TRP, peak chemical heat release rate, and FPI are shown to be important parameters inrnassessing the performance of coated cables. In addition, the performance of the coatings is shown tornbe impacted by the different insulation/jacketing materials to which they are applied.