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Reviewing National Ambient Air Quality Standards (NAAQS)

Updates to Information Presented in the Scope and Methods Plans for the Ozone NAAQS Health and Welfare Risk and Exposure Assessments, May 2012 Memo

You may also be interested in other planning documents from the current ozone National Ambient Air Quality Standards (NAAQS) review.

After the Clean Air Science Advisory Committee (CASAC) Ozone Panel conducted a consultation on EPA’s Scope and Methods Plans for the ozone NAAQS health and welfare risk and exposure assessments in May 2011, EPA began moving forward in developing the first drafts of the risk and exposure assessments for health and welfare effects of ozone. As this work proceeded, EPA determined that changes were needed to certain elements of the scope and methods plan. This memorandum provides an overview of those changes, and reasons for them, to inform the CASAC Ozone Panel and the public as they prepare to review the first drafts of the Risk and Exposure Assessments.

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