The air quality provisions of the Clean Air Act as amended establish restrictions on emission reductions from transportation sources. While Moving Ahead for Progress in the 21st Century Act (MAP-21) is the active transportation legislation providing authorizations for the Federal-aid Highway Program (FAHP) and is codified in Title 23 of the United States Code. The other links provide access to the National Ambient Air Quality Standards (NAAQS) for the criteria pollutants as required by the Clean Air Act, the American Recovery and Reinvestment Act of 2009 and the National Environmental Policy Act (NEPA).
- MAP-21, the Moving Ahead for Progress in the 21st Century Act (P.L. 112-141), was signed into law by President Obama on July 6, 2012. Funding surface transportation programs at over $105 billion for fiscal years (FY) 2013 and 2014, MAP-21 is the first long-term highway authorization enacted since 2005.
- American Recovery and Reinvestment Act of 2009 - President Obama signed the Recovery Act into law on February 17, 2009.
- Clean Air Act - This law defines EPA's responsibilities for protecting and improving the nation's air quality. The last major change in the law was the Clean Air Act Amendments of 1990. Several minor changes have been made since then.
- National Ambient Air Quality Standards (NAAQS) - Details on air quality standards for criteria pollutants, along with information related to the implementation of control programs for each pollutant.
- National Environmental Policy Act (NEPA) - Contains the laws, regulations, and guidance that guide NEPA implementation at FHWA.
- SAFETEA-LU - On August 10, 2005, the President signed into law the Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU). With guaranteed funding for highways, highway safety, and public transportation totaling $244.1 billion, SAFETEA-LU represents the largest surface transportation investment in our Nation's history.
- Title 23, United States Code - Highways