As previously explained in ClassNK Technical Information TEC-0620 issued on 3 February 2005 and TEC-0627 issued on 20 April 2005, SOx Emission Control Areas (hereinafter referred to as SECA) are specified in MARPOL ANNEX VI (hereinafter referred to as ANNEX VI). Ships are subject to stricter SOx emission controls in SECA compared with other sea areas. In this regard, the application of greater SOx emission controls will commence on 19 May 2006 for the Baltic Sea area, which has recently been designated as a SECA.
This ClassNK Technical Information provides information relating to the above matter.

The requirements related to SECA are specified in Regulation 14 of ANNEX VI and are summarized below.

1. Sea areas designated as SECA
The Baltic Sea area and North Sea area have been designated as SECA so far. The definitions of these sea areas are specified in Regulation 10(1)(b) of MARPOL ANNEX I and in Regulation 5(1)(f) of MARPOL ANNEX V, respectively.

2. Time of commencement of SOx emission controls in new SECA
(1) At the Baltic Sea area, the control will commence on 19 May 2006.
(2) At the North Sea area, the control will commence on 22 November 2007.

3. Details concerning SOx emission controls in SECA
While ships are within SECA, either the sulphur content of any fuel oil used onboard ship must not exceed 1.5%m/m*, or otherwise an SOx reducing device must be applied in order to reduce the total emissions of sulphur oxides from the ship to 6.0g/kWh or less.
In the former case, when compliance with the requirements is achieved by changing over to a low sulphur fuel oil from the fuel oil normally used**, it is required that sufficient time be allowed for the fuel oil changeover before entering the SECA, so that the sulphur content of the fuel oil used in the SECA attained by mixing fuel oils does not exceed 1.5%m/m. In addition, the volume of low sulphur fuel oils in each tank as well as the date, time, and position of the ship when any fuel oil changeover is completed, are to be recorded in a log-book.
* The unit "%m/m" means "percent by mass".
** The sulphur content of any fuel oil used onboard ship shall not exceed 4.5%m/m outside SECA.
(To be continued)