The North American Emission Control Area (ECA) is part of the Environmental Protection Agency's coordinated strategy to reduce emissions from large marine diesel engines and their fuels. ECA engine standards and fuel sulfur limits ensure that emissions from all ships that operate in U.S. ports and waters, including foreign vessels, will be reduced significantly, delivering substantial benefits to large segments of the population, as well as to marine and terrestrial ecosystems. In Senate Report 114-281, Congress instructed EPA to consider revising the North American ECA program with respect to ships that generate less than 32,000 horsepower to avoid modal shift resulting in higher emissions. This document provides Congress with a report outlining efforts the EPA has taken to study potential transportation mode shift and describes a new study EPA will perform to answer the Senate Appropriations Committee’s questions.You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.