Policy initiatives > Air pollution from ships > IMO MARPOL Convention

IMO MARPOL Convention

The International Maritime Organization is a UN body for international shipping.

Following its ratification by 15 countries, Annex VI to the International Convention on the Prevention of Pollution from Ships (MARPOL) came into force on 19 May 2005. It was originally signed in 1997.

Annex VI sets limits on the sulphur content of marine heavy fuel oils (with a global cap of 4.5 per cent) and on the emissions of NOx from new ship engines. These standards are however so weak as to be hardly likely to have any appreciable effect.

On the other hand, the annex also sets a limit of 1.5 per cent sulphur for heavy fuel oil used by ships sailing in Sulphur Emission Control Areas (SECAs), which should lead to reductions in the two designated areas, the Baltic Sea and the North Sea.

At its first meeting after the entry into force of the Annex VI, in July 2005, the IMO's Marine Environment Protection Committee (MEPC) agreed on the need to undertake a review aiming at a possible strengthening of the Annex.

The review, originally scheduled to be completed by 2007, should result in new, stricter ship emission standards for SO2 and NOx as well as consideration of measures for reducing emissions of fine particles (PM).

In July 2007, the MEPC created an expert group to examine ways of reducing emissions of SOx. The expert group report, which was published on 21 December, does not make explicit recommendations, but its findings have been submitted to both the IMO’s Bulk Liquids and Gases (BLG) sub-committee and the MEPC for consideration (see Acid News 1/08).

Negotiations on future ship emission standards are now scheduled to be finalized during 2008, primarily at the next meeting of the MEPC to be held in the first week of April, and a final deal is expected to be rubber-stamped by the MEPC in October.