Fire behaviors of polymers under autoignition conditions in a cone calorimeter

Besides piloted ignition, autoignition is also an important aspect to real fire development as combustible materials may be ignited without independent flame. Fire behaviors of non-charring and charring polymers were then investigated in a cone calorimeter under autoignition conditions. Fire risk of non-charring polymers are higher than those of charring polymers because of high heat release, and the increase of heat release rate is much obvious with a higher heat flux or thickness. Charring polymers seem to have a higher CO yield, while non-charring polymers have a higher CO2 yield. Ignition methods have influences to combustion efficiency of non-charring polymers as effective heat of combustion under autoignition are observed lower than those reference data under piloted ignition conditions. Its influences to charring polymers are not obvious. Both CO and CO2 yields under flaming combustion are higher than those under non-flaming combustion, but mass percent of carbon seem to has limited effect. Experimental data in this study can provide a guidance to fire risk evaluation of non-charring and charring polymers.