This concerns the retrofit of NOx-reduction arrangements on large marine diesel engines installed on vessels constructed between 1 January 1990 and 1 January 2000

APPROVED METHOD FOR MAN B&W S50MC ENGINES

On 11 August 2011, the Administration of Denmark notified IMO that they had certified an approved method for engine type MAN B&W S50MC.
IMO published this information on 12 August 2011 in MEPC.1/Circ.765.

This means that all vessels keel-laid between 1 January 1990 and 1 January 2000 that have this engine type installed must
comply with MARPOL Annex VI Reg.13.7 by installing the approved method specified in MEPC.1/Circ.765. This has to take place
no later than the first renewal survey for the IAPP certificate occurring on or after 12 August 2012 (one year after the notification).

It is the shipowner’s responsibility to ensure that the installation takes place within the time limit allowed. However, in order to assist our customers in following
up the requirement, DNV will issue an RR (Retroactive Requirement) for the relevant vessels with this type of engine.

Unfortunately, we may be unable to identify a few vessels. Hence, we urge shipowners to consider whether their vessels are affected by the requirement.

IAPP CERTIFICATE
If the IAPP annual survey is performed before the approved method is installed, “Approved Method exists” is to be ticked in table 2.2.1 in the IAPP Certificate.
When the Approved Method has been installed, both “Approved Method exists” and “Approved Method installed” are to be ticked. It could be worth noting that, for engines
installed on vessels constructed between 1 January 1990 and 1 January 2000 for which no approved method has yet been certified, compliance with Tier I limits is
not required.

In the IAPP Certificate this will be made visible by ticking “Approved Method not commercially available.

SUMMARY OF AVAILABLE APPROVED METHODS AS AT 1 SEPTEMBER 2011:

Please download attached document

Infomarine On-Line Technical Library

File	Description	File size
Retrofit_NOx.pdf	Retrofit of NOx-reduction arrangements on large marine diesel engines.	72 Kb