On 19 May 2005 entered into force new Annex VI of MARPOL Convention – Regulations for the Prevention of Air Pollution from Ships and NOX Technical Code for Diesel Engines. In October 2008 at its 58th session the IMO Marine Environment Protection Committee has been adopted the revisions of actual air pollution prevention requirements. Revised requirements will enter into force on 1 July 2010. This paper presents significant among the revisions which are the phased-in reductions for NOX and SOX emissions and the extended application of NOX emission limits to existing engines;Kołwzan, Krzysztof;Adamkiewicz, Andrzej