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Regulations for Emissions from Vehicles and Engines

Amendments Related to Tier 3 Motor Vehicle Emission and Fuel Standards, Nonroad Engine and Equipment Programs, and MARPOL Annex VI Implementation

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Rule Summary

On February 19, 2015, EPA issued a Direct Final Rule to clarify regulations for the light-duty Tier 3 motor vehicle emissions and fuel standards and for several other mobile source regulations.

The Direct Final Rule included amendments as follows: Corrections to the Tier 3 motor vehicle emission and fuel standards and the Quality Assurance Program; Revisions to the test procedures and compliance provisions for nonroad spark-ignition engines at or below 19 kW; Changes to address ambiguity regarding permissible design approaches for portable fuel containers meeting evaporative emission standards; Revisions to align with current requirements that apply to marine vessels with diesel engines as specified under MARPOL Annex VI; and Corrections to typographical errors in regulatory changes finalized in the Voluntary Quality Assurance Program rulemaking.

EPA received adverse comment on three Tier 3 fuel-related amendments in the Direct Final Rule notice.  EPA withdrew these amendments from the Direct Final Rule and acted on them separately. With the exception of these withdrawn amendments, all of the amendments included in the Direct Final Rule became effective on May 5, 2015.

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