This SAE Recommended Practice is intended for use as a test procedure to determine the gaseous emission levels of diesel engines. Its purpose is to provide a map of an engine's emissions characteristics which, through use of the proper weighting factors, can be used as a measure of that engine's emission levels under various applications. The emission results for hydrocarbons, nitrogen oxides, carbon monoxide, and carbon dioxide are expressed in units of grams per kilowatt hour (grams/brake horsepower hour) and represent the mass rate of emissions per unit of work accomplished. The emissions are measured in accordance with SAE Recommended Practices J177, J215, and J244 using nondispersive infrared equipment for CO and CO2, a heated flame ionization analyzer for HC, and a high performance NDIR or a chemiluminescence analyzer for NOx. All emissions are measured during steady-state engine operation.