The Marine Environment Protection Committee (MEPC) of the International Maritime Organization (IMO) unanimously adopted amendments to the MARPOL Annex VI regulations to reduce harmful emissions from ships even further.

The main changes will see a progressive reduction in sulphur oxide (SOx) emissions from ships, with the global sulphur 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 Sulphur Emission Control Areas (SECAs) will be reduced to 1.00%, beginning on 1 July 2010 (from the current 1.50 %); being further reduced to 0.10 %, effective from 1 January 2015. Progressive reductions in nitrogen oxide (NOx) emissions from marine engines were also agreed, with the most stringent controls on so-called "Tier III" engines, i.e. those installed on ships constructed on or after 1 January 2016, operating in Emission Control Areas.

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

MARPOL Annex VI
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.

Revised NOx Technical Code
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 based on the agreed approach for NOx regulation of existing (pre-2000) engines established in MARPOL Annex VI, 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. Revised Guidelines for Exhaust Gas Cleaning Systems and Guidelines for the development of a VOC management plan were also adopted.

Monumental Decision
Speaking following the adoption of the MARPOL Annex VI amendments, IMO Secretary-General Efthimios Mitropoulos hailed the landmark achievement as "a monumental decision in IMO's history, a decision that proves, once again, that the Organization is focused, united and relevant as the international body capable of dealing with all items on its agenda, an organization that sets global standards in a global environment". The revised measures are expected to have a significant beneficial impact on the atmospheric environment and on human health, particularly that of people living in port cities and coastal communities.

Tacit Amendment Procedure
The amendments enter into force six months after the deemed acceptance date, 1 January 2010, unless within the acceptance period an objection is communicated to the Organization by not less than one third of the Parties or by the Parties the combined merchant fleets of which constitute not less than 50 per cent of the gross tonnage of the world's merchant fleet. Source: https://www.imo.org/[IMO]