Home
gpo.gov
govinfo.gov

e-CFR Navigation Aids

Browse

Simple Search

Advanced Search

 — Boolean

 — Proximity

 

Search History

Search Tips

Corrections

Latest Updates

User Info

FAQs

Agency List

Incorporation By Reference

eCFR logo

Related Resources

The Code of Federal Regulations (CFR) annual edition is the codification of the general and permanent rules published in the Federal Register by the departments and agencies of the Federal Government produced by the Office of the Federal Register (OFR) and the Government Publishing Office.

Download the Code of Federal Regulations in XML.

Download the Electronic Code of Federal Regulations in XML.

Monthly Title and Part user viewing data for the e-CFR is available for download in CSV format.

Parallel Table of Authorities and Rules for the Code of Federal Regulations and the United States Code
Text | PDF

Find, review, and submit comments on Federal rules that are open for comment and published in the Federal Register using Regulations.gov.

Purchase individual CFR titles from the U.S. Government Online Bookstore.

Find issues of the CFR (including issues prior to 1996) at a local Federal depository library.

[A1]

Electronic Code of Federal Regulations

We invite you to try out our new beta eCFR site at https://ecfr.federalregister.gov. We???ve made big changes to make the eCFR easier to use. Be sure to leave feedback using the Help button on the bottom right of each page!

e-CFR data is current as of August 6, 2020

Title 40 → Chapter I → Subchapter C → Part 51 → Subpart CC → §51.1306

Title 40: Protection of Environment
PART 51—REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS
Subpart CC—Provisions for Implementation of the 2015 Ozone National Ambient Air Quality Standards

§51.1306   Redesignation to nonattainment following initial designations.

For any area that is initially designated attainment for the 2015 ozone NAAQS and that is subsequently redesignated to nonattainment for the 2015 ozone NAAQS, any absolute, fixed date applicable in connection with the requirements of this part other than an attainment date is extended by a period of time equal to the length of time between the effective date of the initial designation for the 2015 ozone NAAQS and the effective date of the redesignation, except as otherwise provided in this subpart. The maximum attainment date for a redesignated area would be based on the area's classification, consistent with Table 1 in §51.1303.

[83 FR 63033, Dec. 6, 2018]

Need assistance?