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Regulations for Emissions from Vehicles and Engines

Amendments Related to Marine Diesel Engine Emission Standards – Final Rule

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Rule Summary

EPA is amending the national marine diesel engine program to provide relief provisions to address concerns associated with obtaining and installing certified Tier 4 marine diesel engines in certain high-speed commercial vessels. The relief is in the form of additional lead time for qualifying engines and vessels. EPA is also modifying the marine diesel engine certification program by streamlining engine certification requirements.  These changes will promote Tier 4 certification of engines with high power density.

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