Heat Flux Pipe In Large-scale Fire Tests

Abstract

This paper presents the results from a series of commodity classification tests conducted with a unique flame heat flux instrument, i.e., Heat Flux Pipe. In the early 1990’s, FM Global established the ranking of combustible products with a commodity classification test using benchmark commodities. The methodology used heat release rate calorimetry to determine the hazard level of a commodity. It is well known that flame heat flux is closely linked to flame spread and heat release rates associated with various commodities. In the present test series, the initial sprinklered tests were conducted with Class II and Standard Plastic commodities and a distinct difference in maximum flame heat flux was measured, i.e., 114 kW/m 2 and 192 kW/m 2 respectively. Subsequent freeburn commodity classification tests with Class II, wood pallet and Standard Plastic showed large measured maximum flame heat fluxes, 140 kW/m 2 , 190 kW/m 2 and 440 kW/m 2 respectively. This difference in flame heat flux between commodities can be exploited to better quantify the commodity hazards and hence the corresponding protection requirements. Also, the Heat Flux Pipe has been shown to be a robust instrument in large fires, up to 30 MW, and withstanding flame heat flux level of up to 440 kW/m 2 . The Heat Flux Pipe can clearly be used in other fire scenario where flame