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Clean Air Markets

Clean Air Interstate Rule Historical Reports

The Clean Air Interstate Rule (CAIR) began in 2010 and covers 27 eastern states and the District of Columbia. CAIR was designed to address interstate transport of ozone and fine particulate matter (PM2.5) pollution. The reduction in ozone and PM2.5 formation resulting from implementation of the CAIR programs provides health benefits as well as improved visibility in national parks and improved stream quality in the eastern United States.

The 2009 progress report highlights the results of CAIR. In 2010, EPA began producing reports that combined the results of CAIR, the Acid Rain Program, and the former NOx Budget Trading Program into a single yearly report.

Return to Historical Reports to view progress reports for other programs.

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