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Regulations for Emissions from Vehicles and Engines

Improvements for Heavy-Duty Engine and Vehicle Test Procedures, and other Amendments – Proposed Rule

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Rule Summary

EPA is proposing changes to the test procedures for heavy-duty engines and vehicles to improve accuracy and reduce testing burden. This proposed rulemaking would modify existing test procedures for heavy-duty engines and vehicles. These test procedure changes would improve accuracy, and in some cases, reduce test burden.

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

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