DNV has issued some 2,100 EAPP (Engine Air Pollution Prevention) statements of compliance to engine manufacturers all around the world since 1999, suggesting that the battle to significantly reduce NOx (nitrogen oxides) emissions from ships is being won.

In September 1997, Regulation 13 of Annex VI to MARPOL, which was laid out for ratification among all IMO member states, required certification from all diesel engines installed in ships after January 2000, with respect to NOx emissions.

All work regarding NOx certification is handled by DNV's Machinery Section in its Maritime Technology and Production Centre, a service that was established in 1999 and is still growing with respect to the amount of engines DNV is asked to certify.

MARPOL Annex VI is most likely to be ratified within a matter of months, as 14 of the 15 IMO Member States needed to ratify the protocol have already signed up to the Convention. Several others have indicated that they will sign soon. Annex VI will enter into force 12 months after ratification.

The certification process is divided into two parts: witnessing of emission tests and plan approval of documentation. The first part should be performed by local surveyors from the DNV stations normally seconded to engine manufacturers, while all documentation approval is performed at DNV's dedicated plan approval centre. The approval centre issues the statement or certificate of approval and complies with the requirements for testing and documentation as laid down in the NOx Technical Code to MARPOL.