10 October 2008

At its 58th session in London, the Marine Environment Protection Committee (MEPC) of the International Maritime Organization (IMO) unanimously adopted amendments to the MARPOL Annex VI regulations to introduce more stringent emission standards and fuel sulfur requirements for ships.

The main changes to MARPOL Annex VI will see a progressive reduction in sulfur oxide (SOx) emissions from ships, with the global sulfur cap reduced initially to 3.50% (from the current 4.50%), effective from 1 January 2012; then progressively to 0.50%, effective from 1 January 2020, subject to a feasibility review to be completed no later than 2018.

The limits applicable in Sulfur Emission Control Areas (SECAs) will be reduced to 1.00% from 1 July 2010 (from the current 1.50%); being further reduced to 0.10% effective 1 January 2015.

While heavy fuel oil (bunker fuel) is allowed if it meets the applicable sulfur limit, the new requirements are expected to create increased demand for marine distillate fuels. Alternative measures are also allowed (in the SECAs and globally) to reduce sulfur emissions, such as through the use of scrubbers.

Progressive reductions in NOx emissions from marine engines were also agreed, with global Tier II emission standards effective from 2011. The most stringent Tier III standards apply to ships constructed on or after 1 January 2016, operating in Emission Control Areas. Under the adopted amendments, the Tier I (year 2000) standards also become applicable to large pre-2000 engines (built from 1 January 1990 to 31 December 1999), subject to availability of approved engine upgrade kits.

Adopted Tier II standards—to be met by combustion process optimization—require approximately 20% emission reduction from the current Tier I NOx emission level. The Tier III standards require an 80% NOx emission reduction, expected to be met through such technologies as various forms of water induction into the combustion process (with fuel, scavenging air, or in-cylinder), exhaust gas recirculation, or selective catalytic reduction.

The revised Annex VI will allow for an Emission Control Area to be designated for SOx and PM, or NOx, or all three types of emissions from ships, subject to a proposal from a Party to the Annex, which would be considered for adoption by the IMO, if supported by a demonstrated need to prevent, reduce and control one or all three of those emissions from ships.

There are now only two SECAs—the North Sea and the Baltic. It is expected that European Union countries, the United States, Japan, Singapore and Australia will be declared SECA by 2015.

The revised Annex VI will enter into force on 1 July 2010, under the tacit acceptance amendment procedure.

MARPOL Annex VI Regulations for the Prevention of Air Pollution from Ships entered into force in May 2005 and has, so far, been ratified by 53 countries, representing approximately 81.88% of the gross tonnage of the world’s merchant shipping fleet.

The MEPC also adopted amendments to the associated NOx Technical Code, to give a revised NOx Technical Code 2008. The amended Code includes a new chapter outlining NOx regulation of existing (pre-2000) engines, and provisions for direct measurement and monitoring methods, a certification procedure for existing engines, and test cycles to be applied to Tier II and Tier III engines.

Source: IMO