Polyurethane is a material that can be found in many products that we use in our daily lives. Heating of polyurethanes or polyurethane containing-articles may be necessary during processing and/or product applications. Under normal processing conditions, this may not result in thermal decomposition. However, when heated above normal processing temperatures such as during hot work activities, polyurethanes and other polymers may break down and produce airborne particulates, gases, and/or vapors (i.e., smoke). This breakdown is often referred to as thermal degradation.
Thermal degradation can take place when the material is burning (i.e., flaming) or when it is exposed to elevated temperatures without burning (i.e., non-flaming). All combustible materials, whether natural or synthetic, produce smoke when burned and smoke does contain toxic chemicals. This document highlights potentially hazardous chemicals that may be of concern when polyurethanes undergo thermal degradation, and it provides guidance for worker safety and health as it relates to this topic.