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Regulations for Emissions from Vehicles and Engines

Amendments Related to Marine Diesel Engine Emission Standards – Proposal

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Rule Summary

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EPA proposes to amend the national marine diesel engine program to provide relief provisions to address concerns associated with finding and installing certified Tier 4 marine diesel engines in certain high-speed commercial vessels. The proposed relief is in the form of additional lead time for qualifying engines and vessels. The proposal also includes waiver provisions to allow for continued installation of Tier 3 engines for certain vessels if suitable Tier 4 engines continue to be unavailable. We are also proposing adjustments to the requirements for certifying marine diesel engines, especially as it relates to demonstrating the durability of emission controls, to promote certification of engines with high power density.

EPA is also making a technical correction to the diesel fuel regulations to allow U.S. fuel manufacturers and distributors to sell distillate diesel fuel that complies with the global sulfur standard that applies internationally instead of the fuel standards that otherwise apply to distillate diesel fuel in the United States. Please see the separate final rule for this action here.

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