ANNEX
GUIDELINES FOR MONITORING THE WORLD-WIDE AVERAGE
SULPHUR CONTENT OF RESIDUAL FUEL OILS
SUPPLIED FOR USE ON BOARD SHIPS
Preface
1 The primary objective of the guidelines is to establish an agreed method to monitor the average sulphur content of residual fuel oils supplied for use on board ships. A further objective of the guidelines is to re-open the discussion in MEPC on measures to reduce SOx emissions from ships, should the average sulphur level in fuels, calculated on the basis of these guidelines, show a sustained increase.
Introduction
2 The basis for these guidelines is provided in regulation 14 (2) of Annex VI of MARPOL 73/78 and in Conference Resolution 4 (in MP/CONF.3/35), on monitoring the world wide average sulphur content of residual fuel oil supplied for use on board ships. Among the emissions addressed by Annex VI are emissions resulting from the combustion of fuels containing sulphur. An upper limit for the sulphur content of fuels was set and it was further decided to monitor the average sulphur content of fuel.
It is estimated that independent testing companies undertake up to 50,000 tests annually, which cover between 25 and 35% of all deliveries. From the data gathered by these testing services the current average figures for the sulphur content of residual fuels can be derived. These figures are publicised regularly and are currently in the order of 3% by mass.
Definitions
3 For the purpose of these guidelines the following definitions shall apply:
(1) Residual fuel:
Fuel oil for combustion purposes delivered to and used on board ships with a kinematic viscosity at 100℃ greater than or equal to 10.0 centistoke.1
(2) Provider of sampling and testing services:
A company that, on a commercial basis, provides testing and sampling services of bunker fuels delivered to ships for the purpose of assessing quality parameters of these fuels, including the sulphur content.
(3) Reference value Aw:
The value of the world-wide average sulphur content in residual fuel oils supplied for use on board ships, based on the first three years of data collected and as determined on the basis of paragraph 4 and 5 of these guidelines.
1 Reference is made to ISO Standard 8217, 1996
