Thomas L. Darlington, President


Mr. Thomas Darlington is President of Air Improvement Resource, a company formed in 1994 specializing in mobile source emission modeling. He is an internationally recognized expert in mobile source emissions modeling. He has evaluated the emission benefits and cost effectiveness of nearly every major on-road and off-road regulation proposed and adopted since 1988 in the U.S. and Canada. He has also reviewed and commented on the all of the emission models developed by the EPA and the California Air Resources Board in the 1990s. He has been called upon to testify on such regulations at EPA workshops and hearings, and at ARB workshops and Board Hearings in Sacramento. He also provided expert advice to the National Academy of Sciences during their review of EPA’s MOBILE model. Mr. Darlington currently serves on EPA’s Modeling Working Group reporting to the Mobile Source Technical Review Subcommittee FACA at the request of both the Alliance of Automobile Manufacturers and the Engine Manufacturers Association. The MWG is a stakeholder group of industry, transportation, and government (state and federal) officials that provide feedback to EPA on a broad range of modeling policy issues

Professional Experience

  • 1994-Present -- President, Air Improvement Resource, Inc.
  • 1993-1994 -- Director, Mobile Source Programs, Systems Application International
  • 1989-1994 -- Senior Engineer, General Motors Corporation, Environmental Activities
  • 1988-1989 -- Senior Project Engineer, Detroit Diesel Corporation
  • 1979-1988 -- Project Manager, U.S. EPA, Ann Arbor, Michigan

Recent Major Projects

  • Evaluated the emission benefits of industry alternatives to the California "LEV-II" proposal for cars and light trucks using ARB’s MVEI7G emission model and modeling methods.
  • Modified Canada’s MOBILE5C model to estimate the emission benefits of various vehicle technology and fuel options, and estimated emission benefits across Canada.
  • Analyzed ambient PM10 trends and PM emission inventories in the U.S. over the past ten years, and the implications of further PM controls. This work was published in the Journal of Air and Waste Management.
  • Created an advanced version of the MOBILE6 model that added off-cycle emissions, reduced in-use deterioration, and improved light-duty truck projections, which was used to estimate the benefits of vehicle and fuels options for EPA’s Tier 2 Study for passenger cars and light-duty trucks.
  • Evaluated the emission benefits and cost effectiveness of on-highway emissions control technology applied to off-road large spark ignited engines for the Engine Manufacturers Association and Outdoor Power Equipment Institute.
  • Conducted a comprehensive study of the full fuel cycle emissions of electric vehicles in New York State for the automobile manufacturers.
  • Evaluated the relationship between NOx and ozone in the South Coast Air Basin and in New York on weekends versus weekdays for Navistar International Transportation Corporation.
  • Reviewed all of the EPA technical reports for light- and heavy-duty vehicles for MOBILE6.
  • Evaluated the emission benefits and cost effectiveness of Tier 2 emission standards for small gasoline engines for Engine Manufacturers Association


B. Sc., (Materials and Metallurgical Engineering), University of Michigan, Ann Arbor, 1979

Post Graduate Courses (Business Administration), University of Michigan, Ann Arbor, 1982

.                             Copyright © 2007-2023, Air Improvement Resource, Inc, All Rights Reserved.                               .