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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.

  • Proposed Rule (PDF) (14 pp, 390 K, published September 6, 2019)
    A public hearing related to this proposal is currently planned for 9:30 a.m. on September 20, 2019, at the Maine Maritime Museum in Bath, Maine. See the proposed rule for additional information. Check this page for any changes before traveling to the hearing. Audio access to the hearing will be available with a listen-only teleconference line at (844) 884-8829 (Conference ID = 6273319).

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