The world's top maritime nations are expected to agree to cut the amount of sulfur in fuel used by oceangoing vessels by more than 85 percent in four years.

Cargo ships create about 13 percent of the world's sulfur-dioxide emissions - sizeable, but lower than other industries such as electricity production.  The United Nations World Health Organization says the pollution causes respiratory ailments, and can aggravate existing heart disease.  Hundreds of thousands of premature deaths can be avoided if the shipping sector implements new regulations on sulfur in fuel by the year 2020, instead of delaying it until 2025 as some shippers wish.

The shipping sector is going through one of its worst downturns.  Executives say it would cost the teetering industry around US$40 billion to meet the new rules, and some of the outlays will have to start very soon.  Another problem is availability.  Even if the require to cut sulfur in fuel is pushed back by five years, operators say they doubt refineries would be able to ramp up and make enough of the cleaner fuel to supply the industry even it were to start in 2021.

The International Maritime Organization (IMO) is conducting meetings in London this week to discuss the new emissions rule.  These changes are coming - at issue is whether it will be required by 2020, or if the new rule will be delayed for half a decade.

"The IMO will seek a consensus decision and many major shipping nations have expressed their intention to adopt the 2020 deadline," says a source close to the new regulation as quoted by the Wall Street Journal.  "But it's one country-one vote and if objections are raised it will go to a vote.  In that case, it will be close and can go either way."