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. Regulations for Emissions from Vehicles and Engines

Petitions to Address Harmful Emissions from Locomotives

Petition Summary

On November 9, 2022, EPA responded to petitions submitted by the California Air Resources Board and the San Joaquin Valley Air Pollution Control District. Both of these petitioners requested that the Environmental Protection Agency undertake rulemaking to adopt more stringent national emission standards under the Clean Air Act regulating nitrogen oxide (NOx) and particulate matter (PM) emissions from locomotives.

Background

In 2008, EPA promulgated regulations addressing air pollutant emissions from locomotives. While that rule put in place lower emission standards for new locomotives and new locomotive engines, in California and elsewhere locomotives remain a significant source of NOX and fine particulate matter emissions, often disproportionately impacting the health of communities near railyards and ports. In addition, the very slow natural fleet turnover of this sector results in older locomotives and locomotive engines remaining in use for decades.

Read the CARB Petition (pdf) (489 KB, 2017) and the San Joaquin Valley petition (2016).

Response to Petitions

As part of EPA’s response to these petitions, the Agency is taking immediate steps to focus resources and expertise on developing options and recommendations for new locomotives as well as those that are already operating in communities nationwide. This includes considering appropriate actions for new locomotives in addition to proposing revisions to our existing locomotive preemption regulations to ensure they don’t inappropriately limit California’s and other states’ authorities under the CAA to address their air quality issues.

Further, EPA has formed a rail study team to evaluate how best to address air pollutant emissions from the locomotive sector. This team will collect information and evaluate the following:

  • A range of technologies that may be available to further reduce locomotive emissions;
  • Policy options to accelerate locomotive fleet turnover to newer, cleaner technology;
  • Policy options to ensure that remanufactured locomotives are as clean as possible.

The team will also engage with stakeholders to gather input as needed to inform the required evaluations.

  • EPA’s Response to CARB’s Petition (pdf) (99.58 KB, November 9, 2022)
  • EPA’s Response to San Joaquin’s Petition (pdf) (102.86 KB, November 9, 2022)
  • Fact Sheet: Information about EPA Strategies to Reduce Air Pollution from Locomotives (pdf) (480 KB, November 2022, EPA-420-F-22-030)

Regulations for Emissions from Vehicles and Engines

  • Onroad
    • Passenger Vehicles
    • Commercial Trucks & Buses
    • Motorcycles
  • Nonroad
    • Aircraft
    • Heavy Equipment
    • Locomotives
    • Marine
    • Recreational Vehicles
    • Small Equipment & Tools
  • Greenhouse Gas
Contact Us About Regulations for Emissions from Vehicles and Engines
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on February 14, 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.