AIRCRAFT BLANKET IGNITION AND TOXIC EMISSION IN SIMULATED AIRCRAFT CABIN FIRES USING THE CONE CALORIMETER

摘要

The toxicity and flammability of aircraft cabin blankets was investigated, using a controlledrnatmosphere cone calorimeter with a compartment around the test specimen which was used for controlledrnfire ventilation. A calibrated heated FTIR was used to analyse the toxic gases from the raw fire product gasrnusing a heated gas sampling system. The blankets were tested at a heat flux representative of a developedrnfire and in a ventilation controlled atmosphere at 15 air changes an hour or 20 g/m~2s, typical of that foundrnin an aircraft passenger cabins. The FTIR was calibrated for the analysis of 65 species including all thernsignificant toxic emissions. Six different aircraft blankets were investigated and three that had significantlyrndifferent compositions were fire tested and these included fire retarded and non-fire retarded blankets.rnVertical fire propagation was also investigated. Two phases of burning were observed, flaming andrnsmoldering combustion. The highest toxicity was during the flaming phase, but during the smolderingrnphase there were high concentrations of irritant gases. HCN was the most dominant toxic gas for the twornhigh fuel bound nitrogen blankets and acrolein for the low fuel bound nitrogen specimen blanket. Therernwas evidence of HCl from halogenated flame retardants in the smoldering period. The controlledrnatmosphere cone calorimeter was shown to be a good method for testing materials for their toxic gasrnproduction under realistic ventilation controlled compartment fire conditions. It was recommended thatrnmaterials that could be part of fire initiation in aircraft cabins or elsewhere, should be subject to fire testsrnthat access toxicity levels at realistic fire ventilation conditions. This work shows that some fire blanketsrncould be eliminated from use if test procedures reflected their toxic gas yields, rather than just their firernpropagation and smoke production rates, which is the basis of current aircraft fire material tests.