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Visibility and Haze

Final Clean Air Visibility Rule Will Restore Visibility in America's National Parks and Wilderness Areas

On June 15, 2005, EPA issued final amendments to its July 1999 regional haze rule. These amendments apply to the provisions of the regional haze rule that require emission controls known as Best Available Retrofit Technology, or BART, for industrial facilities emitting air pollutants that reduce visibility. These pollutants include fine particulate matter (PM2.5), and compounds which contribute to PM2.5 formation, such as nitrogen oxides, sulfur dioxides, certain volatile organic compounds, and ammonia. The amendments include final guidelines, known as BART guidelines, for states to use in determining which facilities must install controls and the type of controls the facilities must use.

The memo posted to correct errors (June 27, 2005) prior to the rule publication is available below. Also available are the rule fact sheet and the Regulatory Impact Analysis.

Note: the most recent revisions to the Regional Haze Rule were finalized in January 2017. 2017 Regional Haze Final Rule

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