Skip to Content

We invite you to try out our new beta eCFR site at We’ve made big changes to make the eCFR easier to use. Be sure to leave feedback using the 'Feedback' button on the bottom right of each page!

Proposed Rule

Release of the Policy Assessment for the Review of the Primary National Ambient Air Quality Standards for Oxides of Nitrogen

Document Details

Information about this document as published in the Federal Register.

Document Statistics
Document page views are updated periodically throughout the day and are cumulative counts for this document. Counts are subject to sampling, reprocessing and revision (up or down) throughout the day.
Published Document

This document has been published in the Federal Register. Use the PDF linked in the document sidebar for the official electronic format.

Start Preamble


Environmental Protection Agency (EPA).


Notice of availability.


The Environmental Protection Agency (EPA) is announcing the availability of the final document titled Policy Assessment for the Review of the Primary National Ambient Air Quality Standards for Oxides of Nitrogen (NO2Start Printed Page 17948PA). Nitrogen dioxide (NO2) is the component of oxides of nitrogen (NOX) for which we have the greatest concern for public health. Accordingly, the current primary (health-based) National Ambient Air Quality Standards (NAAQS) for NOX are in terms of NO2. The NO2 PA presents considerations and conclusions relevant for the EPA's review of the primary NO2 NAAQS. The primary NO2 NAAQS are set to protect the public health from exposures to NO2 in ambient air.


The NO2 PA will be available on or about April 12, 2017.


The NO2 PA will be available primarily via the Internet at:​naaqs/​nitrogen-dioxide-no2-primary-standards-policy-assessments-current-review.

Start Further Info


Ms. Breanna Alman, Office of Air Quality Planning and Standards (Mail Code C504-06), U.S. Environmental Protection Agency, Research Triangle Park, NC 27711; telephone number: 919-541-2351; email:

End Further Info End Preamble Start Supplemental Information


Two sections of the Clean Air Act (CAA) govern the establishment and revision of the NAAQS. Section 108 (42 U.S.C. 7408) directs the Administrator to identify and list certain air pollutants and then to issue air quality criteria for those pollutants. The Administrator is to list those air pollutants that in his “judgment, cause or contribute to air pollution which may reasonably be anticipated to endanger public health or welfare;” “the presence of which in the ambient air results from numerous or diverse mobile or stationary sources;” and “for which . . . [the Administrator] plans to issue air quality criteria . . .” Air quality criteria are intended to “accurately reflect the latest scientific knowledge useful in indicating the kind and extent of all identifiable effects on public health or welfare which may be expected from the presence of [a] pollutant in the ambient air . . .” 42 U.S.C. 7408(b). Under section 109 (42 U.S.C. 7409), the EPA establishes primary (health-based) and secondary (welfare-based) NAAQS for pollutants for which air quality criteria are issued. Section 109(d) requires periodic review and, if appropriate, revision of existing air quality criteria. Revised air quality criteria reflect advances in scientific knowledge on the effects of the pollutant on public health or welfare. The EPA is also required to periodically review and, if appropriate, revise the NAAQS based on the revised criteria. Section 109(d)(2) requires that an independent scientific review committee “shall complete a review of the criteria . . . and the national primary and secondary ambient air quality standards . . . and shall recommend to the Administrator any new . . . standards and revisions of the existing criteria and standards as may be appropriate . . .” Since the early 1980s, this independent review function has been performed by the Clean Air Scientific Advisory Committee (CASAC).

Presently, the EPA is reviewing the criteria and the primary NAAQS for NOX. The EPA released the final Integrated Science Assessment for Oxides of Nitrogen—Health Criteria (the ISA) in January 2016. Drawing from the ISA, a draft NO2 PA was prepared by the EPA's Office of Air Quality Planning and Standards, within the Office of Air and Radiation. The draft NO2 PA presented preliminary staff conclusions on the adequacy of the current standards and addressed key policy-relevant science issues that guided the review. The draft NO2 PA was reviewed by the CASAC at a public meeting on November 9-10, 2016, and a teleconference on January 24, 2017. The CASAC's advice on the draft NO2 PA was conveyed in a letter to the Administrator dated March 7, 2017.[1] The final NO2 PA being released at this time reflects consideration of the CASAC's advice and public comments received on the draft NO2 PA.

Start Signature

Dated: April 10, 2017.

Stephen Page,

Director, Office of Air Quality Planning and Standards.

End Signature End Supplemental Information


[FR Doc. 2017-07558 Filed 4-13-17; 8:45 am]