Flexible Polyurethane Foams: A Comparative Measurement of Toxic Vapors and Other Toxic Emissions in Controlled Combustion Environments of Foams With and Without Fire Retardants

摘要

A series of experiments were performed to measure the toxic vapor emissions of fires involving flexible polyurethane foams (FPUF) with and without flame retardants (FR). FPUF were covered with FR and non-FR fabrics to simulate cushion conditions. Testing was performed to both maximize detection of gases in small scale testing and measurement of exposure concentrations in realistic fire conditions in a room sized enclosures. A standard smoke box with load cell, open flame ignition source and Fourier transform infra-red spectrometer (FTIR) fit with a 2 m gas cell was used to monitor gas emission real time during testing with filter samples analyzed for acid gases and chloro-dioxins and furans. An NFPA 286 room was used to measure realistic smoke emissions from three seat furniture mock-ups with non-combustible frames. Oxygen consumption calorimetry, smoke opacity and smoke toxicity were measured during these tests. FTIR and grab sampling were performed during the room fires. Grab sampling using evacuated metal canisters were used to collect combustion gasses at various stages of the fire followed by analysis using EPA method TO-15 indoor air pollutants. In addition chloro-dioxins and furans were measured using a particulate filter collection system. The results of the study indicated that both FR and non-FR FPUF gave very similar results for smoke toxicity and both were less than what would be produced by an equivalent mass of wood. Use of fire barrier materials increased the toxicity of smoke produced from non-FR FPUF due to the creation of oxygen limited conditions. Use of fire barrier materials with FR FPUF would not sustain ignition and ended up producing less toxic smoke for up to 19 kW ignition source.