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  2. Regulations for Emissions from Vehicles and Engines

Proposed Rule and Correction for Control of Air Pollution From New Motor Vehicles: In-Use Testing for Heavy-Duty Diesel Engines and Vehicles

Proposed Rule and Correction for Control of Air Pollution From New Motor Vehicles: In-Use Testing for Heavy-Duty Diesel Engines and Vehicles
Basic Information
Code of Federal Regulations Citations
  • 40 CFR Part 86

On this page:

  • Rule Summary
  • Additional Resources

Rule Summary

Related Topic
  • Final Rule for Control of Emissions of Air Pollution From New Motor Vehicles: In-Use Testing for Heavy-Duty Diesel Engines and Vehicles

The U.S. Environmental Protection Agency (EPA) is proposing a manufacturer-run, in-use emissions testing program for heavy-duty diesel trucks. This proposal is the first step in implementing a June 2003 settlement agreement between the Engine Manufacturers Association (EMA) and EPA. Under this in-use testing program, manufacturers will measure gaseous and particulate exhaust emissions from diesel engines using portable onboard emission measurement systems. This cooperative effort represents a significant advance in helping to ensure that the benefits of more stringent emission standards are realized under real-world driving conditions.

  • Proposed Rule Correction: Control of Air Pollution From New Motor Vehicles: In-Use Testing for Heavy-Duty Diesel Engines and Vehicles (pdf) (229 KB, published June 21, 2004)
  • Proposed Rule: Control of Emissions of Air Pollution From New Motor Vehicles: In-Use Testing for Heavy-Duty Diesel Engines and Vehicles (pdf) (213 KB, published June 10, 2004)

Additional Resources

  • Fact Sheet: Proposed In-Use Testing Program for Heavy-Duty Diesel Engines and Vehicles (pdf) (116 KB, EPA420-F-04-042, June 2004)
  • Draft Technical Support Document: Proposed In-Use Testing Program for Heavy-Duty Diesel Engines and Vehicles (pdf) (623 KB, EPA420-D-04-003, June 2004)

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Last updated on May 12, 2025
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