Federal Register

The Federal Register is the official daily publication for rules, proposed rules, and notices of federal agencies and organizations. EPA publishes the following actions relating to air quality State Implementation Plans (SIPs) in the Federal Register:

• Proposals for approval of SIP revisions;
• Public participation opportunities for proposed SIP actions; and
• Final approval actions.

Daily issues are available online at Federal Register.

How to comment on proposed SIP actions in the Federal Register

EPA makes electronic copies of state SIP submissions available to the public. The Federal Register notice for each rulemaking action contains information about how to locate the public docket at www.regulations.gov for reviewing and submitting comments.

Many state air quality agencies also make SIPs available for public review on their own websites.

Code of Federal Regulations

Once approved by EPA, SIPs are published in the Code of Federal Regulations. 

The annual version of the Code of Federal Regulations (CFR) contains EPA's official actions on SIPs (see Title 40, Part 52).

The Electronic Code of Federal Regulations (e-CFR) contains current updates to the CFR (generally within two business days). However, for legal research purposes, the e-CFR is not an official edition of the CFR. It is an unofficial editorial compilation of CFR material and Federal Register amendments.

While every effort has been made to ensure that the e-CFR is accurate, those relying on it for legal research should verify their results against the official editions of the CFR, Federal Register, and List of CFR Sections Affected - available online at www.fdsys.gov. Visit the e-CFR Frequently Asked Questions for more information about the legal status of the e-CFR.