Fire Performance Testing of WPCs at the Forest Products Laboratory

Wood-plastic composites represent a growing class of materials used by the residential construction industry and the furniture industry. For some applications in these industries, the fire performance of the material must be known, and in some cases improved. Lab-scale fire performance tests allow for comparisons between WPC formulations. At the Forest Products Laboratory (FPL) oxygen index tests and cone calorimetry are typically used during fire performance evaluations of WPCs. This paper describes these tests and presents a case study applying these methods for evaluation of wood flour-polyethylene composites containing fire retardants. In the case study we compared the results of wood-polyetheylene composites with unfilled polyethylene and solid wood and then evaluated the effect of five additive-type fire retardants on fire performance. Using these test methods we could identify the most promising fire retardants for wood-polyethylene composites.