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Regulations for Emissions from Vehicles and Engines

Final Rule for Control of Emissions of Air Pollution From Nonroad Diesel Engines and Fuel

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Rule Summary

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Referenced Tier Level

  • Tier 4

In 2004, EPA finalized Tier 4 emission standards for nonroad diesel engines and sulfur reductions in nonroad diesel fuel will dramatically reduce harmful emissions and will directly help States and local areas recently designated as 8-hour ozone nonattainment areas to improve their air quality. This comprehensive national program regulates nonroad diesel engines and diesel fuel as a system.

Rule History

Additional Resources

Fact Sheet

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