United States Federal Government
  Agency for Healthcare Research and Quality
  Department of Transportation, Federal Highway Administration
  Environmental Protection Agency
  Health Resources and Services Administration
  Institute of Museum and Library Services
  National Institutes of Health
  Small Business Administration
State and Local Governments
  Alaska Department of Environmental Conservation
  Arizona Department of Environmental Quality
  California Air Resources Board
  City of Sacramento
  Georgia Department of Natural Resources
  Houston Advanced Research Center
  Massachusetts Department of Environmental Protection
  Metropolitan Washington Council of Governments
  Pennsylvania Department of Environmental Protection
  Pennsylvania Department of Transportation
  Port Authority of New York/New Jersey
  Sacramento Metropolitan Air Quality Management District
  Tennessee Department of Transportation
  Texas Commission on Environmental Quality
  Virginia Department of Transportation
Regional Air Planning Organizations
  Central States Air Resource Agencies
  Lake Michigan Air Directors Consortium
  Mid-Atlantic/Northeast Visibility Union
  Ozone Transport Commission
  Visibility Improvement State and Tribal Association of the Southeast
  Western Governors Association
Other Organizations
  Center for Climate Strategies
  Coordinating Research Council