The International Consortium for Fire Safety, Health, and the Environment (ICFSHE), with funding provided by the Outdoor Power Equipment Institute, awarded a contract to the SP Swedish National Testing and Research Institute (SP) for a “Scientific Evaluation of the Risk Associated with Heightened Environmental Requirements on Outdoor Power Equipment.” As part of this study ICFSHE requested that the Building and Fire Research Laboratory of the National Institute of Standards and Technology (BFRL/NIST) provide experimental support to SP. A work statement was adopted that involved characterizing the ignition of typical outdoor fuels by ignition sources representative of those expected for outdoor power equipment exhaust systems. This report summarizes the findings of the BFRL/NIST investigation. One series of experiments was designed to simulate the ignition behaviors of fuels that come into direct contact with a heated surface.