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Regulations for Emissions from Vehicles and Engines

Improvements for Heavy-Duty Engine and Vehicle Test Procedures - Final Rulemaking

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Rule Summary

EPA is finalizing changes to the test procedures for heavy-duty engines and vehicles to improve accuracy and reduce testing burden.

EPA is also making other regulatory amendments concerning light-duty vehicles, heavy-duty vehicles, highway motorcycles, locomotives, marine engines, other nonroad engines and vehicles, and stationary engines.

These amendments affect the certification procedures for exhaust emission standards and related requirements. EPA is finalizing similar amendments for evaporative emission standards for nonroad equipment and portable fuel containers.

These amendments would:

  • Streamline the regulations which will reduce industry costs
  • Increase compliance flexibility
  • Harmonize with other requirements
  • Clarify existing requirements
  • Correct errors

Additional Resources

Regulations for Emissions from Vehicles and Engines Home