The Environmental Protection Agency's (EPA) Office of Mobile sources initiated this study in order to assess the existing and potential impact of aircraft emissions on localair quality at ten selected cities. The scope of this study: (1) selected ten cities with current or potential local air quality problems; (2) estimated the emissions from commercial jet aircraft only (on board auxiliary power units excluded); (3) relied on the methodology in EPA's Procedures for Emission Inventory Preparation, Volume 4: Mobile Sources, 1992 (PB92-209386); (4) sought data from sources that are national in scope and readily available, and (5) used 1990 as the base year, with 2010 as the projection year for potential emissions growth. This study confirms that commercial aircraft emissions significantly contribute to air pollution in the ten study areas. This study creates a basis understanding of ground-level aircraft emissions contribution, verifies that investigation of cost-effective control options on aircraft emissions is warranted, and highlights the need for improvements in the quality of national level data if more certainty is desired.

"April 1999."

Introduction -- Estimating commercial jet aircraft emissions -- Aircraft emissions analysis results -- Aircraft emissions contribution -- Conclusions -- Appendices: A. Health effects of aircraft emissions -- B. Emissions calculation methodology -- C. Ozone nonattainment area maps -- D. Airport activity projections -- E. Time- in- mode data and assumptions -- F. Aircraft/ engine emission factor database -- G. Facility- specific and regional emissions summaries -- H. EPA regional emission estimates for 1990 and 2010.