A comprehensive literature review on the thermal decomposition products and combustion toxicity of phenolics is presented. The major decomposition products of phenolics appear to be CO, CO2, H2O, and methane. Smaller quantities of H2, formaldehyde, and other volatile organics, including phenol, methylphenols, and dimethylphenols, also appear to be produced. The types and quantities of thermal decomposition products and the temperatures at which they are produced depend on numerous factors, including the resin structure and formulation and the conditions of degradation. Phenolics produced products that were indicated to be more acutely toxic than other cellular plastics tested by one researcher and were described as “more toxic than wood” by another researcher. Carbon monoxide appears to be the major toxicant produced by the combustion of phenolics. Sensory irritation as indicated by reduced respiratory rate may be due to formaldehyde production; however, sensory irritation is lower than that produced by wood.
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