US EPA

The EPA Office of Air Quality Planning and Standards (OAQPS) and Office of Research and Development's Center for Public Health and Environmental Assessment (CPHEA) are preparing an Integrated Review Plan (IRP) and an Integrated Science Assessment (ISA) as part of the latest review of the air quality criteria and the National Ambient Air Quality Standards (NAAQS) for ozone (O3) and related photochemical oxidants.

The IRP will summarize the plan for the review, including the initial identification of policy-relevant issues and questions to frame the review. The ISA will build on the scientific assessment conducted for the last O₃ review, focusing on assessing newly available information since the last assessment. Interested parties are invited to assist the EPA by submitting information regarding significant new O₃ research and policy-relevant issues for consideration in this review of the primary (health-based) and secondary (welfare-based) O₃ standards.

In its periodic review of the air quality criteria, the EPA reviews the currently available scientific information and prepares an ISA. The ISA and other key documents prepared in the review receive independent and expert scientific review by the CASAC.

Photochemical oxidants, including O₃, are one of six “criteria” pollutants for which EPA has established NAAQS, and O₃ is the current indicator for that NAAQS. The O₃ NAAQS were most recently revised in fall of 2015. In consideration of the statutory deadline for the next periodic review of the air quality criteria and standards, the EPA is accelerating initiation of the planning phase for the review, including development of the IRP for the review.

The IRP will describe the overall plan for the review, outlining the anticipated schedule, process, and approaches for evaluating the relevant scientific information, as well as the key policy-relevant issues that will frame the review. We intend that the IRP will build upon key documents from the last review (available from: https://www.epa.gov/​naaqs/​ozone-o3-air-quality-standards). Such documents include the preamble to the final rulemaking decision, which included detailed discussions of policy-relevant issues central to that review (80 FR 65292, October 26, 2015), and the Integrated Science Assessment (ISA) for Ozone and Related Photochemical Oxidants (Final Report, Feb. 2013), EPA/600/R-10/076F.

Interested parties are invited to assist the EPA by submitting information regarding significant new O₃ research and policy-relevant issues for consideration in this review of the primary (health-based) and secondary (welfare-based) O₃ standards.

To ensure this final statutory requirement is fully met, elsewhere in the June 26, 2018 Federal Register, EPA is issuing a call for information that would facilitate the committee's consideration of these issues.

EPA will consult with the CASAC on the IRP and will also solicit comments from the public. As the review proceeds, the EPA will also request CASAC review of, and provide an opportunity for public comment on, other draft documents prepared for the review, which generally include the ISA, a risk/exposure assessment (REA), as warranted, and a policy assessment (PA). The EPA intends to provide the CASAC with a standardized set of key charge questions to consider in providing advice to the Administrator throughout the entire review, supplementing these questions with more detailed requests as necessary.

More information on the updated process for the forthcoming ozone NAAQS review, including statutory, standardized charge questions, is contained in the Administrator's May 9, 2018 memorandum, “Back-to-Basics Process for Reviewing National Ambient Air Quality Standards.”