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Technical

Highlights

 Printed on Recycled Paper

United States

Environmental Protection

Agency

Air and Radiation EPA420-F-99-044

December 1999

Office of Mobile Sources

Responsibilities for Marine Vessel

Operators with EPA-Certified Diesel

Engines

Which engines are affected by the new emission

standards?

In general, emission standards and related requirements start for new

commercial marine diesel engines manufactured in 2004 or later for

engines with displacement less than 2.5 liters per cylinder. This corresponds to a power rating of about 600 kW for a 12-cylinder engine.

Standards begin to apply for bigger engines that are manufactured in

2007 or later. In some limited cases, the standards also apply to remanufactured or other used engines. We allow certain exemptions and

flexibilities for a wide variety of situations. See the “Scope of Application” fact sheet (EPA420-F-99-047) for more information about when

standards apply for individual engines. We plan to set emission standards for recreational marine diesel engines in the near future.

The U.S. Environmental Protection Agency’s (EPA’s) final rule for

commercial marine diesel engines rated over 37 kilowatts (kW) sets

emission standards that apply to new engines used in the United States.

These standards take effect for new engines manufactured starting in

2004, 2005, or 2007 depending on the size of the engine. This fact sheet

informs marine vessel operators of their responsibilities under the final

rule.
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The emission limits of MARPOL Annex VI apply to engines before the

EPA standards start. Also, EPA standards do not apply to engines with

displacement over 30 liters per cylinder, so the MARPOL Annex VI

limits continue to apply to these engines after the EPA standards start.

See the fact sheet on MARPOL Annex VI (EPA420-F-99-038) for more

information.

What do I need to know about engine labels?

Every certified engine needs a label showing that it meets the requirements that apply to it. The label includes several things, including the

model year and useful life of the engine and its tune-up specifications

and adjustments. The label may also show that the engine is certified

only for certain applications or for a certain fuel.

What requirements apply to rebuilding engines?

Engines with a label must be rebuilt to their original configuration. See

the fact sheet on rebuilding diesel engines (EPA420-F-99-045) for

additional information.

What is tampering?

If you disable the engine’s emission control system or make other

changes to the engine that increase its emissions, you could be guilty of

tampering with a certified engine. You can make changes to the engine

without violating the requirements if you have a reasonable basis to

believe that you are not increasing the engine’s emissions. This should

generally include emission test data showing emissions levels before and

after the change.

How do emission standards affect the

manufacturer’s warranty?

The engine manufacturer must provide a warranty for emission-related

components for the period specified on the engine label. If they provide

you with a longer warranty (either written or negotiated) for components

unrelated to emission controls, that longer warranty period also applies

to all your emission-related components. Emission-related components

generally include anything the manufacturer has added to the engine to

meet emission standards.
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Do emission standards affect the way I maintain my

engines?

The manufacturer may not require you to use specific parts or repair

facilities, but it is still your responsibility to maintain your own engines.

The manufacturer will have maintenance instructions showing what is

needed to ensure that the engine and its emission control systems will

work properly. If you don’t do these things, high emission rates could

occur and the manufacturer’s warranty may no longer be valid.

What aftermarket parts may I use?

Companies may certify their parts to show that the engine will still meet

our requirements, but we don’t require it. If you select or install parts that

disable or seriously compromise the engine’s emission control system,

this may be an engine tampering violation. This could result either from

low-quality parts or from parts that are designed to optimize engine

performance at the expense of emission control.

For More Information

See 40 CFR 94 for additional details. For more information on commercial marine diesel engines, visit the Office of Mobile Sources’ web site

at:

http://www.epa.gov/oms/marine.htm

You can also contact Bob Montgomery at:

U.S. Environmental Protection Agency

Office of Mobile Sources (6403J)

401 M Street SW

Washington, DC 20460

(202) 564-9287

e-mail: montgomery.robert@epa.gov