Toxicant production in under-ventilated compartment fires assessed by laser absorption spectroscopy

The production of incomplete combustion products from the burning of wood, medium density fiberboard (MDF), and nylon in an under-ventilated compartment fire was investigated using a reduced-scale compartment. Species measurements of carbon monoxide (CO) and carbon dioxide (CO 2 ) were performed using Fourier Transform Infrared Spectroscopy (FTIR) and methane (CH 4 ), hydrogen cyanide (HCN), benzene (C 6 H 6 ), ethylene (C 2 H 4 ) and acetylene (C 2 H 2 ) were measured with Laser Absorption Spectroscopy (LAS) with three different interband cascade lasers. The fuels were burned in three different crib configurations; only wood, only MDF, and a mixture of wood and nylon, to examine the production of different toxicants. During the experiments, measurements were collected of CO, CO 2 , CH 4 , HCN, C 2 H 2 , and C 6 H 6 species from the gas exiting the compartment, gas temperature from inside the compartment, and the flow into and out of the compartment. Consistent with under-ventilated combustion, the temperature inside the compartment typically exceeded 600 °C. CO was measured during all experiments and was two orders of magnitude less than the measured CO 2 concentration. Significant amounts of unburned hydrocarbons were measured during all of the experiments, while HCN was only detected during the wood-nylon tests. Higher toxicant yields were measured for wood-nylon compared to pure wood and MDF.