Environmental Technology

SOx – shipping’s newest target

Malcolm Latarche
Malcolm Latarche

08 November 2018

SOx – shipping’s newest target

As this a is article is being completed there is just over a year for shipowners to determine what strategy they will adopt to meet the 2020 reduction on the global cap on permitted sulphur content in fuels.

The reduction from a maximum of 3.5% sulphur to just 0.5% is aimed at dramatically cutting the level of SOx emissions attributable to the shipping industry. Emissions are covered by the same MARPOL Annex VI as NOx but the rules and the timelines involved are quite different. As with NOx, individual states are free to impose different regulations on vessels entering their ports or waters and this has been done in several areas of the world, notably the EU and China.

The Regulation of SOx began when Annex VI became effective in 2005. This was done in two ways. Firstly, the level of sulphur permitted in fuels was regulated according to a reducing level over a period of 15 to twenty years through to 2020 or 2025. The permitted levels are as follows:

Outside an ECA established

to limit SOx and particulate matter emissions

Inside an ECA established to limit SOx and particulate matter


4.50% m/m prior to 1 January 2012

1.50% m/m prior to 1 July 2010

3.50% m/m on and after 1 January 2012

1.00% m/m on and after 1 July 2010

0.50% m/m on and after 1 January 2020 (2025)*

0.10% m/m on and after 1 January 2015

*The final reduction of the global cap was to be decided following a review of the likely availability of compliant fuel that was to be completed by the end of 2018. In the event this review was done in 2016 and the 2020 date was confirmed.

Secondly, MARPOL Annex VI allows the designation of certain areas as emission control areas (ECAs) the first of these was the Baltic Sea which was designated as a SECA (sulphur emission control area) in 2005 with the rules applying from 2006. A second SECA – The North Sea SECA was established the following year.

Seven years later the first of two ECAs in the Americas was established followed by another two years later. In these two ECAs both NOx and SOx are controlled. These four regions are currently the only places were SOx is controlled by international regulation but there is talk of a new ECA being established in the Mediterranean and there are other places around the globe where local regulations exist. In these areas, the permitted level of sulphur allowed in fuels or the level of SOx emitted is significantly reduced.

The timeline for SOx regulation covered in Annex VI is as follows:

  • • 26 Sept 1997 - Annex VI formally adopted
  • • 19 May 2005 - Annex VI enters into force Sulphur level in fuel set at – 4.5% global, 1.5% ECA
  • • 19 May 2006 - Baltic Sea SECA established
  • • 11 Aug 2007 - EU implements North Sea SECA prematurely
  • • 21 Nov 2007 - Official IMO date for North Sea SECA
  • • 17 Jul 2009 - MEPC approves proposed US/Canada ECA (SOx, NOx and PM)
  • • 1 July 2010 - SOx 1.0% ECA
  • • 1 July 2011 - MEPC approves proposed US Caribbean ECA (SOx, NOx and PM)
  • • 1 Jan 2012 - SOx 3.5% global
  • • 1 Aug 2012 - Implementation of US/Canada ECA
  • • 1 Jan 2014 - Implementation of US Caribbean ECA
  • • 1 Jan 2015 - SOx 0.1% ECA
  • • October 2016 – MEPC 70 Completes of review into availability of low-sulphur fuel
  • • 1 Jan 2020 - SOx 0.5% global

EU SOX Regulations

The basic EU legislation for regulating sulphur emissions from ships was Directive 1999/32/EC. This was amended by Directive 2005/33/EC, which designated the Baltic Sea, the North Sea and the English Channel as sulphur emission control areas (SECAs) approved and adopted by the IMO and limited the maximum sulphur content of the fuels used by ships operating in these sea areas to 1.5%. The same fuel standards also applied to passenger ships operating on regular service in EU waters outside of the controlled areas.

From 1st January 2010 when the 2005 directive came into force, as well as reinforcing the limits of sulphur for vessels operating in SECAs and limiting the sulphur content of fuels used ashore in the EU, it also introduced legislation governing the maximum sulphur content of fuels used by inland waterway vessels and ships at berth in Ports which are part of the European Community. The limit for ships in ports was set at 0.1% Sulphur, which is the maximum sulphur content of Gas Oil under ISO standards.

The rules permit some leeway in that they allow ‘sufficient time’ for the crew to complete any necessary fuel changeover operation as soon as possible after arrival at the berth and as late as possible before departure. Ships in port for period less than one hour of those that connect to shore electricity supplies are exempt from the requirement.

Considering the IMO timeline for sulphur levels, the EU is now only out of step in applying the 0.1% limit to ports outside of the two SECA zones.

Just as the EU was premature in imposing regulation in the two European SECAs, it has also done this in respect of reducing the global cap from 3.5% to 0.5%. Although the IMO only took that decision in 2016, EU Directive 2012/33/EU had already laid down a maximum sulphur content of 0.5% for fuel used outside the European ECAs in the territorial waters and exclusive economic zones of EU member countries for the year 2020.

Chinese Regulation

China is another country that has imposed its own regulation with the Air Pollution Control (Marine Light Diesel) Regulation 01/04/2014. This introduced a new sulphur content cap of 0.05% for the locally supplied marine light diesel (MLD). In addition, Hong Kong’s Environmental Protection Department has required all ocean-going vessels to use low-sulphur fuel, defined in the new legislation as fuel with sulphur content not exceeding 0.5% by weight, when at berth in Hong Kong waters. All such ships must initiate fuel switch upon arrival at berth, complete the switch to low sulphur fuel within one hour, then use low sulphur fuel throughout the berthing period until one hour after departure.

On 4 December 2015, China announced the establishment of further ship ECAs in the Pearl River Delta, the Yangtze River Delta and the Bohai Bay rim area. The regulation applies to all merchant ships navigating, anchored or under operation in the waters of the control areas. With effect from 1 January 2016, ships were required to follow the requirements current international conventions or local laws/regulations (whichever is stricter) on the emission control of SOx, particulates and NOx. If the port condition allows, ports within control areas may implement stricter requirements than current conventions, regulations such as requiring use of fuel with 0.5% m/m Sulphur content or below.

The implementation schedule for the Chinese requirements is:

  • • 1 January 2016, some ports (if the port condition allows) within the control areas may implement the requirement for use of fuel with 0.5% m/m sulphur content or below when ships are alongside or at anchor. Note that this is for any port within the control area, not just the key/core ports;
  • • 1 January 2017, key/core ports of control areas implement the requirements for use of fuel with 0.5% m/m sulphur content or below when ships are alongside or at anchor;
  • • 1 January 2018, all ports within control areas shall implement requirements for use of fuel with 0.5% m/m sulphur content or below when ships are alongside or at anchor; and
  • • 1 January 2019, ships entering into control areas shall use fuel with 0.5% m/m sulphur content or below.

It should be noted that following an assessment of the effects of the above actions China will possibly implement requirements for use of fuel with 0.1% m/m Sulphur content or below after 31 December 2019. The requirements for ships at berth or at anchor are applicable from one hour after ships are berthed to one hour before departure. Ships may use other alternative measures to reduce emissions, such as shore power, clean energy systems or scrubbers.