This is due to the large range of available fire retardants found in polyurethane foams, which suggests that the toxicity will likely follow the general trends in the literature for all materials regarding fire retardants. Garrido and Font (2015) reported two main steps in the inert-atmosphere decomposition of flexible polyurethane foams. Hydrogen cyanide is approximately 25 times more toxic than carbon monoxide through the formation of the cyanide ion, which is formed by hydrolysis in the blood (Hartzell 1993). depends on the mass loss rate of the specimen and the available air; for most methods one or both are unknown; will be increased by an unknown factor if products are recirculated into the flame zone. There is some contradiction the literature as to the effect fire retardants have on the overall toxicity of polyurethane foams. The carbon dioxide release by the reaction in Scheme2 can act as a blowing agent in polyurethane foam production and up to a point the amount of water added will be inversely proportional to the density of the foam. Polyol fragments in the gas phase will also begin to decompose at >800C to produce simple organic fragments and PAHs. MDI is a diaromatic diisocyanate compound that boils at 208C and is primarily used in the production of rigid foams. The rigid polyurethane foam produced slightly more CO than the polyisocyanurate at ~2.0 (240mgg1 vs 225mgg1). Busker RW, Hammer AH, Kuijpers WC, Poot CAJ, Bergers WWA, Bruijnzeel, PLB (1999) Toxicity testing of combustion products of polyurethane and polyvinylchloride. National Fire Protection Association, Quincy, MA, pp 5482, Guo X, Wanga L, Zhanga L, Lia S, Hao J (2014) Nitrogenous emissions from the catalytic pyrolysis of waste rigid polyurethane foam. (1986) investigated the toxicity of flexible polyurethane foam and a polyester fabric both separately and together. The applied heat flux must be large enough for burning to continue at oxygen concentrations as low as 5%. The overall toxicity of the polyisocyanurate foam shows a clear increase as the fire became more under-ventilated, while the rigid polyurethane foam showed a slight decrease at 1.242.00. Manage cookies/Do not sell my data we use in the preference centre. Springer Nature. National Bureau of Standards, Washington D.C. Levin BC, Paabo M, Fultz ML, Bailey C, Yin W, Harris SE (1983a) Acute inhalation toxicological evaluation of combustion products from fire-retarded and non-fire retarded flexible polyurethane foam and polyester. The lowest temperature at which a liquid will give off vapors at a sufficient rate to support a momentary flame across its surface is known as its: . Off-gassing & Outgassing: What's the Difference? Where is it From The polyester based foam produced nearly double the amount of HCN between 900 and 1000C than the polyether foam with an increase from 20.8mgg1 to 38.0mgg1. In this modification, the controlled atmosphere cone calorimeter (CACC) (Babrauskas et al. The incapacitating Ct product corresponds to CO at a dose of 35 000LL1min (approximately equal to ppm min), predicting incapacitation at around 1200ppm for 30min exposure, and an exponential relationship for HCN (because asphyxiation by HCN exposure does not fit a linear relationship), predicting incapacitation at around 82ppm for 30min exposure. The authors presented a large set of data for all of the test methods, including a range of test conditions, air flow rates, oxygen concentration, and mass loadings.
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