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In Maine, EPA Finalizes Action on Certain Marine Diesel Engines Providing Regulatory Relief for American Lobstermen and Pilot Boat Captains

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Kennebunkport, Maine (August 20, 2020) — Today, at a press conference with the Maine Lobstermen’s Association, U.S. Environmental Protection Agency (EPA) Administrator Andrew Wheeler finalized amendments to the national marine diesel engine program to address the lack of available certified Tier 4 marine diesel engines for use in certain high-speed commercial vessels. This final rule provides much needed regulatory relief to boat builders and manufacturers of lightweight and high-power marine diesel engines. Specifically, this action will benefit America’s hardworking lobster fishermen and pilot boat captains, who rely on these engines for safe and productive operations in their high-speed commercial vessels.

“This relief gives boat builders and operators flexibility to meet EPA standards during the next several years,” said EPA Administrator Andrew Wheeler. “Lobstermen and pilot boat captains are at a particular disadvantage when changes in emission rules occur, because the larger market for diesel engines can’t build new models quickly enough for marine users – putting these operators in potential violation of pollution rules through no fault of their own.”

“This is great news for the First District and our ports,” said U.S. Congressman Earl L. “Buddy” Carter (GA-01). “This rule will ensure bar pilots in Savannah and Brunswick are able to get the boats they need to do their jobs. Without this change to the rules, the pilots could have been forced to scale back their critical work which is required for every ship to enter and exit both the Ports of Savannah and Brunswick. The ports could have been devastated without this rule change. Instead, they will now be able to keep cargo traffic moving. I thank the EPA for their hard work on this issue.”

“We appreciate the EPA listening to and addressing the concerns of hard working Lobstermen and boatbuilders from Maine. Delaying the implementation of the Tier 4 requirements for Commercial Fishing boats allows the industry to better address safety and availability issues,” said Maine Lobstermen's Association President Kristan Porter.

“Due to the unique design of Maine lobster boats, at this time there are not Tier 4-compliant diesel engines available on the market that can safely fit in these types of vessels. This delay in the implementation of the Tier 4 emission standards for commercial lobster-style boats should provide engine manufacturers time to design and certify engines that will both comply with Tier 4 emission standards and work safely and efficiently in these boats. It also prevents lobstermen from being burdened by requirements that are impossible to meet with the currently available technology,” said U.S. Senators Susan Collins and Angus King and U.S. Representatives Chellie Pingree and Jared Golden in a joint statement. “We are pleased to have worked together with the EPA to find a commonsense solution that supports Maine boat builders and lobstermen.”

Without today's regulatory relief, boat builders would be unable to build these types of high-speed vessels, leaving those in the market for a new boat the choice between either purchasing underpowered, unsuitable vessels or using existing vessels with older, dirtier engines.

This final action amends EPA’s existing rules to allow for the continued installation of Tier 3 engines in new vessels for a limited time – until 2022 or 2024, depending upon the size and type of vessel. This in turn will help those boat builders who have found themselves unable to obtain the certified engines they need to construct the specialized vessels with the size and power characteristics required by their customers, such as lobster fisherman and pilot boat operators. In addition, the final amendments provide for a waiver process to accommodate the situation should suitable Tier 4 engines continue to be unavailable in the future.

The rule also streamlines the engine certification process to reduce the costs of  compliance and certification for engine manufacturers. This will promote entry into the market engines with the sort of high power density characteristics that these specialized, high performance vessels require. As a result, EPA predicts the retirement of older vessels with dirtier engines and their replacement by new vessels utilizing cleaner high-performance Tier 4 engines.


In 2008, EPA adopted Tier 4 emission standards for new commercial marine diesel engines at or above 600 kW. The deadline for compliance with these new standards depended on an engine’s power rating, with some new engines being required to comply in 2014 and others in later years, with the final compliance deadline coming in 2017. After the Tier 4 standards were fully in effect for all engine sizes, EPA came to learn that, for certain types of high-speed commercial vessels that utilized engines with rated power between 600 and 1,400 kW and which required engines with high power density (as measured in kW per liter displacement), certified Tier 4 engines with these performance characteristics remained wholly unavailable for new vessel construction. This action responds to those regulatory problems in a focused manner that accommodates the needs of these small but vital commercial interests, while at the same time being careful to preserve the progress EPA has been making in reducing emissions from marine diesel engines.

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