EPA proposed new regulations on April 30 to reduce nitrogen oxides (NOx) and particulate matter (PM) from new large marine diesel engines used primarily for propulsion power on ocean-going vessels such as container ships, tankers, bulk carriers and cruise ships. While the vessels that use these engines can be flagged in the United States
and in other countries, the proposed standards would apply only to engines on U.S.-flagged vessels. Manufacturers of these marine diesel engines have already implemented engine changes to reduce NOx emissions. The marine diesel engine contribution to local NOx inventories can be high in commercial ports where they operate, which are often located in ozone non-attainment areas. In Baton Rouge/New Orleans, La., and Wilmington, N.C., these marine engines contribute about seven percent of mobile source NOx. In Miami/Fort Lauderdale, Fla., and Corpus Christi, Texas, they account for about five percent of NOx. In addition, these ships can have a significant impact on inventories in coastal areas without large commercial ports such as Santa Barbara, Calif., where it is estimated that engines on ocean-going marine vessels contribute about 37 percent of total NOx. Large marine diesel engines account for about three percent of national mobile source PM emissions. PM exposure from diesel exhaust can irritate and inflame lungs and potentially aggravate asthma symptoms, especially in children. Most of the particulate emissions from these engines is a result of the high sulfur content of the fuel used. EPA is also requesting comment on whether a fuel sulfur content limitshould be set for the fuel used in these engines. An April 30 deadline to have a proposed rulemaking signed is part of EPA's settlement agreement with the Earth Island Institute. The proposal and related documents are available at: www.epa.gov/otaq.