While land-based industry has been subject to strenuous emissions regulations over the past decades, air emissions from sea-going ships’ machinery has so far been largely unregulated. As a result, according to EU statistics, ships have become the single biggest source of sulphur dioxide (SO2) within the EU. The US EPA (US Environmental Protection Agency) reports similar findings, i.e., that the proportion of air pollutants released which can be attributed to the shipping industry is increasing. MARPOL Annex VI aims to reduce emissions from ships through international regulations, which hopefully will discourage states from enacting unilateral regulations problematic to the shipping industry.

MARPOL Annex VI Regulation 14 restricts SO2 emissions from ships by introducing a maximum Sulphur content in marine fuels of 4.5 per cent. In addition, MARPOL Annex VI identifies SO2 emission control areas (SECA); in these areas the maximum Sulphur content of marine fuels used is 1.5 per cent. Ships found not to be in compliance with Annex VI may be detained by port state control inspectors. Also, sanctions for violations may be determined by local law where the violation occurs or the law of the flag state.

Ship owners must ensure that all ships of 400 GT or above, and all platforms and drilling rigs engaged in voyages to ports and waters where the MARPOL convention applies, have a valid International Air Pollution Prevention Certificate (IAPPC) confirming compliance with both the equipment and operational requirements of Annex VI.

In order to reduce SO2 emissions many ship owners are fitting gas scrubbers and catalysers to reduce emissions from their vessels, however, the efficiency of these systems should be constantly monitored to ensure compliance with the regulations.

Up until now monitoring systems have been units designed for large combustion processes which were not designed for the task. CODEL has now designed an in-situ SO2 analyser specifically designed for sea-going duty and for the aggressive environment found on ships. For further information please contact our marine industry partner Azurtane Ltd who are experts in marine emissions abatement technology and monitoring gaseous emissions,