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Regulations for Emissions from Vehicles and Engines

Direct Final Rule for Heavy-Duty Engine and Vehicle, and Nonroad Technical Amendments

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Rule Summary

EPA and National Highway Traffic Safety Administration (NHTSA), on behalf of the Department of Transportation, are each adopting corrections to provisions in our respective Medium- and Heavy-Duty Greenhouse Gas Emissions and Fuel Efficiency final rule issued on September 15, 2011. These amendments eliminate duplicative reporting requirements, reduce inadvertent minor differences between the EPA and NHTSA programs regarding such matters as voluntary early model year compliance, better align testing procedures to market realities, and reduce unnecessary testing burdens. 

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