Spark-Ignition Engine Emission Deterioration Factors for the Draft NONROAD2004 Emissions Model

摘要

This report addresses the emission deterioration rates for spark-ignition engines currently being used in the draft NONROAD2004 model. The specific deterioration inputs used in NONROAD and their basis will be addressed for spark-ignition engines at or below 25 horsepower and over 25 horsepower, as well as liquid petroleum gas (LPG) and compressed natural gas engines (CNG). Deterioration inputs for compression-ignition (diesel) engines are addressed in the report, Exhaust Emission Factors for Nonroad Engine Modeling - Compression Ignition (NR-009b). The EPA welcomes comments and suggestions concerning our approach to modeling nonroad engine emissions deterioration.