The proposal requires IMO to designate these waters as an ’emission control area’, mandating any large ship including tankers, container vessels and cruise ships operating in these areas to use cleaner fuel or install better emission control technology.

In addition, the new regulation will need the ships that are built after January 1, 2016 to meet more stringent standards for nitrogen oxides if they operate in the Caribbean emission control area.

By 2020, the measurements are estimated to reduce the emissions of sulfur dioxides from ships by 96%, fine particles by 86% and nitrogen oxides by nearly 30% at the emission control area from the levels they would otherwise have been at without the designation.

The area of the proposed US Caribbean emission control area includes waters adjacent to coasts of the Commonwealth of Puerto Rico and the US Virgin Islands, while the northern and southern boundaries would extend 50 and 40 nautical miles, respectively, from the main island of Puerto Rico.

EPA regional administrator Judith Enck said that the sulfur, soot and other harmful air pollutants from large ships reach from ports to inland communities, the designation will result in cleaner air for residents of Puerto Rico and the US Virgin Islands and the millions of tourists who visit these islands.