The United States Caribbean Sea Emission Control Area (ECA) (SOx came into effect, under MARPOL Annex VI, on 1 January 2014, bringing in stricter controls on emissions of sulfur oxide (SOx), nitrogen oxide (NOx) and particulate matter (PM) for ships trading in certain waters adjacent to the coasts of Puerto Rico and the United States Virgin Islands.
The ECA was designated under MARPOL amendments adopted in July 2011. There are now four three designated ECAs in effect globally:
- The new United States Caribbean Sea ECA (SOx, NOx and PM);
- the North American ECA (SOx, NOx and PM);
- the Baltic Sea ECA (SOx); and
- the North Sea ECA (SOx).