Effects of storage height on critical delivered flux of representative fuels

Fire suppression experiments were conducted to determine the critical delivered fluxes (CDFs) of representative fuels. The objective was to evaluate the CDF-based commodity classification for sprinkler protection purposes with emphasis on the effects of storage height. The experiments were carried out in 2- and 5-tier double-row, rack storage configurations, which, together with previous 3-tier work, provide a complete set of CDF measurements at different storage heights. The experimental results show that the 5-tier CDFs correlate well with full-scale sprinkler testing experiences. The comparison of CDFs also reveals the storage height effects for different fuels: the CDF values scale linearly for the cartoned commodities, while nonlinearities are observed for the uncartoned plastic commodities. Based on these results, a commodity classification method is proposed to assess solid combustible materials in the real world with separate treatment of cartoned and uncartoned fuels.