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Regulations for Emissions from Vehicles and Engines

Final Rule for Control of Emissions of Air Pollution from 2004 and Later Model Year Heavy-Duty Highway Engines and Vehicles; Revision of Light-Duty On-Board Diagnostics Requirements

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Rule Summary

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In this rule, EPA finalized a new program to reduce emissions from on-highway, heavy-duty engines and vehicles. These reductions will provide for cleaner air and greater public health protection, primarily by reducing ozone pollution. This program was the first phase of a multi-phase strategy to reduce emissions from heavy-duty engines and vehicles.

Rule History

Additional Resources

Fact Sheet


Regulations for Emissions from Vehicles and Engines Home