Skip to main content
U.S. flag

An official website of the United States government

Here’s how you know

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

HTTPS

Secure .gov websites use HTTPS
A lock (LockA locked padlock) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

    • Environmental Topics
    • Air
    • Bed Bugs
    • Cancer
    • Chemicals, Toxics, and Pesticide
    • Emergency Response
    • Environmental Information by Location
    • Health
    • Land, Waste, and Cleanup
    • Lead
    • Mold
    • Radon
    • Research
    • Science Topics
    • Water Topics
    • A-Z Topic Index
    • Laws & Regulations
    • By Business Sector
    • By Topic
    • Compliance
    • Enforcement
    • Laws and Executive Orders
    • Regulations
    • Report a Violation
    • Environmental Violations
    • Fraud, Waste or Abuse
    • About EPA
    • Our Mission and What We Do
    • Headquarters Offices
    • Regional Offices
    • Labs and Research Centers
    • Planning, Budget, and Results
    • Organization Chart
    • EPA History

Breadcrumb

  1. Home
  2. State and Local Transportation

Current Law, Regulations and Guidance for State and Local Transportation

  • Clean Air Act - Conformity Section This link includes Clean Air Act Section 176(c) as amended by the 2005 transportation act known as “SAFETEA-LU".
  • Transportation Conformity Regulations (pdf) (42 pp, 288 KB, EPA-420-B-12-013, April 2012) This document reflects all transportation conformity rulemakings promulgated by EPA as of April 13, 2012, including the Restructuring Amendments final rule and the MOVES Regional Grace Period Extension final rule.
  • Chronological List of Transportation Conformity Rulemakings EPA has published rule amendments in the Federal Register since transportation conformity was enacted as part of the 1990 Clean Air Act. These rulemakings include preamble text explaining rule provisions that remain in effect today.
  • Baseline Year for the Baseline Year Test (in 40 CFR 93.119) Refer to this page for a table showing the baseline year to be used for each NAAQS and the regulatory provision where it is found.
  • Policy and Technical Guidance: EPA and the U.S. Department of Transportation have issued a number of guidance documents that provide additional information on implementing the conformity regulations.

For more information, contact Laura Berry at 734-214-4858 or berry.laura@epa.gov.

State and Local Transportation

  • Transportation & Conformity
  • Vehicle Emissions Inspection & Maintenance (I/M)
  • Greenhouse Gas Planning
  • State Implementation Plans (SIPs)
  • Modeling & Calculator Tools
Contact Us About State and Local Transportation
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on April 22, 2025
  • Assistance
  • Spanish
  • Arabic
  • Chinese (simplified)
  • Chinese (traditional)
  • French
  • Haitian Creole
  • Korean
  • Portuguese
  • Russian
  • Tagalog
  • Vietnamese
United States Environmental Protection Agency

Discover.

  • Accessibility Statement
  • Budget & Performance
  • Contracting
  • EPA www Web Snapshot
  • Grants
  • No FEAR Act Data
  • Plain Writing
  • Privacy
  • Privacy and Security Notice

Connect.

  • Data
  • Inspector General
  • Jobs
  • Newsroom
  • Regulations.gov
  • Subscribe
  • USA.gov
  • White House

Ask.

  • Contact EPA
  • EPA Disclaimers
  • Hotlines
  • FOIA Requests
  • Frequent Questions
  • Site Feedback

Follow.