This study addresses the fire behavior of bed assemblies, including a mattress, foundation and bedclothes. The focus is on development and application of a reproducible means of simulating the thermal impact which burning bedclothes materials impose on a mattress. Twelve dtfferent sets of bedclothes were burned on top of an inert mattress to obtain data on heat release rate, flame spread rates and, to a lesser degree, heat flux to nearby objects. Six of these sets were selected for characterization of the heat flux patterns they impose on an inert mattress surface. A unique, infrared imaging technique was developed for this purpose. The results, in terms of peak heat flux, duration and area, were used to develop a pair of propane burners which impose on the side and top of a mattress heat flux patterns which mimic those imposed at a typical, fixed location by burning bedclothes. These burners were applied to a set of five mattress designs, including one typical of current residential mattresses; the four other designs included potentially less flammable design elements to permit a wide range of fire behaviors. This facilitated a broad assessment of the ability of the gas burners to predict the fire behavior of mattresses. The duration of the burner application was varied. Also, as a check on the burner-induced behavior, the same mattress designs were tested with one bedclothes combination. All of the altered designs offered some modification in fire behavior but they differed strongly in overall effect. The effects ranged from a delay in the time to reach an undiminished heat release rate peak to greatly reduced mattress involvement in the fire. The burners successfully predicted the behavior of four of the mattress designs. They failed to predict the fire behavior (with burning bedclothes) of one design since the bedclothes produced a phenomenon (internal overpressurization and seam rupture) which the burners did not produce.
Citation: NIST Interagency/Internal Report (NISTIR) - 6497Report Number:
NIST Pub Series: NIST Interagency/Internal Report (NISTIR)
Pub Type: NIST Pubs
mattresses, flammability, methodology, beds (furniture), bedding, fire spread, heat flux, heat release rate, fire behavior, gas burners