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Regulations for Emissions from Vehicles and Engines

Final Rule for Procedures for Testing Highway and Nonroad Engines and Omnibus Technical Amendments

Rule Summary

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The U.S. Environmental Protection Agency (EPA) is revising the procedures for testing various categories of nonroad engines. We are also applying these same procedures to heavy-duty highway engines. This common set of test requirements is intended to streamline laboratory efforts for EPA and industry and to form the basis for internationally harmonized test procedures for nearly all categories of engines. This final rule also covers a wide range of amendments to EPA regulations for most highway and nonroad sectors.

Rule History

Additional Resources

Fact Sheet

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