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Regulations for Emissions from Vehicles and Engines

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

On this page:

Rule Summary

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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.

Rule History

Proposed Rule and Related Materials

Additional Resources

Technical Support Document

Fact Sheet

Regulations for Emissions from Vehicles and Engines Home