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General Conformity

General Conformity Training Module 1.4: More Information

1.4.1 Revisions to the General Conformity Regulations

EPA initially promulgated the General Conformity rule in 1993. Subsequently EPA collected information from other federal agencies on how to maintain the same environmental protections while streamlining the General Conformity implementation process. This information was used to develop and propose revisions to the General Conformity rule.  After soliciting comments on these revisions from the public, EPA issued a final rule revision on April 5, 2010. This revised rule  improves the process federal entities use to demonstrate that their actions will not contribute to a NAAQS violation, provides tools to encourage better communication and air quality planning between states and federal agencies, and encourages both the federal agencies and the states to take early actions to ensure projects will conform to the state’s plans to implement the NAAQS. The revised General Conformity rule and additional information are available on EPA's General Conformity website at

1.4.2 General Conformity Questions and Answers

On June 05, 2006, EPA released a memorandum noting recent revisions to EPA's general conformity regulations questions and answers document. The memo is available on EPA's General Conformity website,, under "Revision to General Conformity Applicability Questions and Answers."

1.4.3 General Conformity: Airports

On September 30, 2004 and September 25, 2002, the Federal Aviation Administration and EPA released documents regarding General Conformity Regulations as applied to airports. These documents are available on EPA's General Conformity website,

1.4.4 General Conformity: Contact Information

You can learn more about how General Conformity affects your area by contacting your local or state air quality office or the EPA Regional Office. Links to these air quality offices can be found at

1.4.5 Where can I get more information on General conformity?

The General conformity regulations, initially published on November 30, 1993 and revised on March 24, 2010, are found at 40 CFR part 93, subpart B

List of nonattainment and maintenance areas