"EPA is proposing changes to the regulations at 40 CFR part 80, subpart I, to allow for distribution and sale of distillate diesel fuel that complies with the 0.50 percent (5000 ppm) global sulfur standard contained in MARPOL Annex VI starting in 2020. These regulatory changes will accommodate the supply and distribution of distillate diesel fuel as global marine fuel.
Ocean-going vessels and large ships traditionally used “bunker fuel” with sulfur levels as high as 5%, or 50,000 ppm, sulfur. Bunker fuel burned on these ships was a large source of harmful air pollution in the U.S.
An international treaty designated two Emission Control Areas (ECA) covering U.S. waters. The North America ECA extends 200 miles from the shores of North America, and the U.S. Caribbean Sea ECA covers waters around Puerto Rico and the U.S. Virgin Islands. The sulfur content of the fuel used in marine vessels operating in these ECAs may not exceed 0.10 weight percent (1000 ppm).
Note that a global sulfur cap of 3.50 weight percent applies outside of ECA boundaries. This limit decreases to 0.50 weight percent in 2020."
