Preface
1 The primary objective of the Guidelines is to establish an agreed method
to monitor the average sulphur content of fuel oils supplied for use on board ships
taking into account the different sulphur limits as required by regulation 14 of the
revised MARPOL Annex VI.
Introduction
2 The basis for these Guidelines is provided in regulation 14.2 of the
revised Annex VI of MARPOL and in Conference Resolution 4 (in MP/CONF.3/35), on
monitoring the worldwide average sulphur content of residual fuel supplied for use on
board ships, and document MEPC 59/24. Among the emissions addressed by Annex VI are
emissions resulting from the combustion of fuel oils containing sulphur. An upper limit
for the sulphur content of fuel oils was set and it was further decided to monitor the
average sulphur content of fuel oils. Monitoring of the worldwide average sulphur
content of distillate fuel supplied for use on board ships is not specified in
regulation 14.2 of Annex VI. However, in the meantime, it was agreed to monitor the
average sulphur content of distillate fuel.
3 The independent testing companies analyse over 100,000 samples 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 publicized regularly and are currently in the order of
2.4% by massfootnote.
Definitions
4 For the purpose of these Guidelines the following definitions should apply:
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.1 Residual fuel:
Fuel oil for combustion purposes delivered to and used on board ships with a
kinematic viscosity at 40˚C greater than 11.00 centistokesfootnote (mm2/s).
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.2 Distillate fuel:
Fuel oil for combustion purposes delivered to and used on board ships with a
kinematic viscosity at 40˚C lower than or equal to 11.00 centistokesfootnote (mm2/s).
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.3 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.
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.4 Reference value Awr:
The value of the worldwide average sulphur content in residual fuels supplied for
use on board ships, based on the first three years of data collected and as
determined on the basis of paragraphs 5 to 11 of these Guidelines.
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.5 Reference value Awd:
The value of the worldwide average sulphur content in distillate fuels supplied
for use on board ships, based on the first three years of data collected and as
determined on the basis of paragraphs 5 to 11 of these Guidelines.
Monitoring and calculation of yearly and three-year rolling averages
Monitoring
5 Monitoring should be based on calculation of average sulphur content of residual and
distillate fuels on the basis of sampling and testing by independent testing services.
Every year the average sulphur content of residual and distillate fuels should be
calculated. After three years the reference value for monitoring will be set as
described in paragraph 11.
Calculation of yearly averages
6 At the basis of monitoring is the calculation, on an annual basis, of the average
sulphur content of residual and distillate fuel.
7 The calculation of the average sulphur content is executed as follows:
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For a certain calendar year, the sulphur contents of the samples analysedfootnote (one sample for each delivery of which the sulphur
content is determined by fuel oil analysis) are recorded. The sulphur contents of
the samples analysed are multiplied by the corresponding mass of fuel oils added
up and then divided by the total mass of bunker analysed. The outcome of that
division is the average sulphur content of residual and distillate fuels for that
year.
8 As a basis for well-informed decisions a graphical representation of the distribution
of the global sulphur content plotted against the quantity of fuel oils associated with
each incremental sulphur content range should be made available by 31 January of each
year:
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.1 residual fuels: in terms of the % sulphur in increments of 0.5% sulphur;
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.2 distillate fuel for sulphur content below 0.5%: in terms of the % sulphur in
increments of 0.1%; and
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.3 distillate fuels for sulphur content above 0.5%: in terms of the % sulphur in
increments of 0.5%.
9 The mathematical formula for the method of calculation described is given in the
appendix to these Guidelines.
Three-year rolling average
10 A three-year rolling average should be calculated as follows:
Setting of the reference values
11 The reference value of the world wide average sulphur content of residual and
distillate fuels supplied for use on board ships should be Awx, where x=r, d,
and Awx = Acr as calculated in January of the year following the
first three years in which data were collected on the basis of these Guidelines.
Aw should be expressed as a percentage.
Providers of sampling and testing services
12 There are presently four providers of sampling and testing services under these
Guidelines.
13 Any additional providers of sampling and testing services will be approved by the
MEPC in accordance with the following criteria:
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.1 be subject to the approval of the Marine Environment Protection Committee,
which should apply these criteria;
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.2 be provided with a technical and managerial staff of qualified professionals
providing adequate geographical coverage and local representation to ensure
quality services in a timely manner;
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.3 provide services governed by a documented Code of Ethics;
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.4 be independent as regards commercial interest in the outcome of monitoring;
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.5 implement and maintain an internationally recognized quality system, certified
by an independent auditing body, which ensures reproducibility and repeatability
of services which are internally audited, monitored and carried out under
controlled conditions; and
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.6 take a significant number of samples on an annual basis for the purpose of
globally monitoring average sulphur content of residual and distillate fuels.
Standardized method of calculation
14 Each of the providers of sampling and testing services should provide the necessary
information for the calculation of the average sulphur content of the residual and
distillate fuels to the Secretariat of IMO or another agreed third party on the basis of
a mutually agreed format, approved by MEPC. This party will process the information and
will provide the outcome in the agreed format to MEPC. From the viewpoint of competitive
positions the information involved should be considered sensitive.
APPENDIX
CALCULATION OF AVERAGE SULPHUR CONTENT BASED ON QUANTITY
Note: wherever "all deliveries" are mentioned, this is meant to refer to
all deliveries sampled and tested for sulphur and being taken into account for the
purpose of monitoring.