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Regulations for Emissions from Vehicles and Engines

Final Rule for Technical Amendments to the Highway and Nonroad Diesel Regulations

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Rule Summary

EPA is taking direct final action to correct, amend, and revise certain provisions of the Highway Diesel Rule, and the Nonroad Diesel Rule. This action corrects additional errors and omissions from the previous rules, and it makes minor changes to the regulations to assist entities with regulatory compliance. This action also makes technical amendments that resulted from discussions with various diesel stakeholders. These technical amendments will: provide a temporary increase in the sulfur testing tolerance, revise the designate and track provisions to account for non-petroleum diesel fuels (i.e., biodiesel) and fuel that meets the California Air Resources Board’s diesel fuel standards, and amend the alternative defense provisions to account for conductivity additives and red dye. This action is intended to help facilitate compliance with the diesel fuel regulations and ensure a smooth transition to ultra low sulfur diesel fuel.

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