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  2. Regulations for Emissions from Vehicles and Engines

Final Rule for Control of Emissions of Air Pollution From Highway Heavy-Duty Engines

Final Rule for Control of Emissions of Air Pollution From Highway Heavy-Duty Engines
Basic Information
Code of Federal Regulations Citations
  • 40 CFR Part 9
  • 40 CFR Part 86

On this page:

  • Rule Summary
  • Rule History
  • Additional Resources

Rule Summary

The Environmental Protection Agency (EPA) is adopting a new combined emission standard for oxides of nitrogen (NOx) and hydrocarbons (HC) for model year 2004 and later heavy-duty diesel engines used in trucks and buses. The new standard represents a 50 percent reduction in NOx from the 1998 and later model year NOx standard.

  • Final Rule: Control of Emissions of Air Pollution From Highway Heavy-Duty Engines (PDF)(37 pp, 432 K, published October 21, 1997)
  • Final Regulatory Impact Analysis (PDF)(144 pp, 3 MB, EPA-420-R-97-011, September 1997)
  • Summary and Analysis of Comments: Control of Emissions of Air Pollution from Highway Heavy-Duty Engines (PDF)(81 pp, 8 MB, September 1997, EPA-420-R-97-102)

Rule History

Proposed Rule and Related Materials

  • Proposed Rule (PDF)(25 pp, 359 K, published August 31, 1995)

Additional Resources

Technical Support Document

  • Estimated Economic Impact of New Emission Standards for Heavy-Duty On-Highway Engines (PDF)(87 pp, 422 K, EPA-420-R-97-009, March 1997)

Fact Sheet

  • New Emission Standards For HeavyDuty Diesel Engines Used In Trucks And Buses (PDF)(4 pp, 14 K, EPA-420-F-97-016, October 1997)

Regulations for Emissions from Vehicles and Engines

  • Onroad
    • Passenger Vehicles
    • Commercial Trucks & Buses
    • Motorcycles
  • Nonroad
    • Aircraft
    • Heavy Equipment
    • Locomotives
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  • Greenhouse Gas
Contact Us About Regulations for Emissions from Vehicles and Engines
Contact Us About Regulations for Emissions from Vehicles and Engines to ask a question, provide feedback, or report a problem.
Last updated on April 18, 2024
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