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Spot sampling and analysis of a ship’s fuel is becoming increasingly common as a means for port state control officers to verify the actual sulphur content of the fuel in use.

On 22 August 2016 Transport Canada (TC) started to rigorously monitor all ships operating within the Canadian jurisdiction of the North American Emission Control Area (NA-ECA) to ensure they are using fuel containing not more than 0.10 per cent sulphur by mass. According to their Ship Safety Bulletin No.08/2016, Canadian marine safety inspectors may request samples of fuel to be drawn from the ship’s fuel service system during routine inspections and will use portable fuel analysers to measure the sulphur content of the sample. Depending on the results of the analysis, or if a portable analyser is not available, the inspector may also forward the sample to an accredited laboratory to confirm compliance with the fuel oil sulphur content requirements.


The shipping industry is facing increasingly stricter air emission limits all over the world, e.g. through MARPOL Annex VI, EU Directive 1999/32/EC and other regional regulations. Ships berthed in EU ports have used marine fuel with a sulphur content not exceeding 0.10 per cent since 1 January 2010. The 0.10 per cent sulphur cap on fuel in use within the NA-ECA has been in force since 1 January 2015, and in the State of California since 1 January 2014. A more recent example is China’s introduction of a 0.50 per cent sulphur cap in three major port regions. As shipowners and operators continue to meet applicable sulphur oxides emission limits by changing to compliant low sulphur fuel prior to entering one of the regulated areas, use of onboard spot sampling of a ship’s fuel is becoming increasingly common as a means for port state control officers (PSCOs) to verify compliance.


Sulphur “content-in fuel” inspections

A ship may be targeted for a sulphur inspection for various reasons, e.g. the existence of a previous non-compliance or warning received concerning its fuel, the ship is scheduled to bunker at a specific port, or as part of a maritime safety administration’s enhanced verification programme. In the EU for example, a Commission Implementing Decision 2015/253 lays down the rules and establishes a mandatory frequency of sulphur inspections for each Member State based on the number of port calls in the respective state. It also requires a certain percentage of these ships to have the sulphur content of the marine fuel being used on board checked by sampling or analysis or both.

In order to establish whether a ship is in compliance, PSCOs will examine documentation onboard such as bunker delivery notes, ships’ log books, written procedures for fuel oil change-over, International Air Pollution Prevention (IAPP) certificate issued under MARPOL Annex VI, tank plans and diagrams etc. - and frequently a sulphur inspection will be limited to these checks. However, where there is doubt about a ship’s ability to properly manage the lower sulphur fuel oil onboard and prevent it being mixed or contaminated with higher sulphur oils, PSCOs may request to draw samples from the fuel oil supply lines or tanks as well.



  • Prepare for inspections: Masters and engine crews onboard ships operating on two different sulphur grades of fuel oil should familiarise themselves with the sulphur emission limits applicable within their trading area - and be well prepared for a sulphur inspection. In addition to having the relevant onboard documentation in order, and easily available to the PSCO, procedures should ensure that samples of fuel can be drawn safely from the ship’s fuel service system when such sampling is requested by the attending PSCO.
  • Identify suitable and safe locations for sampling: In the absence of a dedicated sample valve approved by the flag state/classification society, the ship’s representative should be able to propose a location for sampling that is representative of the fuel in use, typically downstream of the service tank and as close to the fuel oil combustion machinery as possible. However, as the introduction of sampling points into a pressurised fuel pipeline introduces a risk of fire and explosion, safety is paramount when proposing a location. The sampling location should be shielded from any heated surfaces or electrical equipment so as to preclude impingement of fuel onto such surfaces or equipment under all operating conditions. Arrangements for suitable drainage to a safe location should also be considered.
  • Retain sample bottles onboard: Fuel samples may be taken at more than one location in the fuel service system to try to ensure that the risk of contamination from other sources is unlikely. For each sample drawn during an inspection, the ship’s representative should ensure that a properly sealed and labelled sample bottle is retained onboard the ship. It is advisable to keep the sample bottles for a period of not less than 12 months from the date of collection.

Available guidance

The European Maritime Safety Agency (EMSA) has published a “Sulphur Inspection Guidance” which provides useful advice and information on the PSCO’s approach to the inspection of ships and how they ascertain the vessel’s compliance with applicable sulphur in fuel requirements. i.e. the EU sulphur directive 1999/32/EC as amended. Section 2.7 of the EMSA guidance addresses sample collection and analysis and recommends a location for sampling to fulfil the following conditions:

  • be easily and safely accessible;
  • take into account the different fuel grades used for the fuel-oil combustion machinery items;
  • be downstream of the fuel in use from the service tank; and
  • be as close to the fuel inlet of the fuel-oil combustion item as is possible and in a safe location, taking into account the type of fuels, flow-rate, temperature, and pressure behind the selected sampling point.

Members and clients may also be aware that in February 2016, at its 3rd session, the IMO Sub-Committee on Pollution Prevention and Response (PPR) agreed on a draft MEPC circular on “Guidelines for onboard sampling for the verification of the sulphur content of the fuel used onboard ships” for submission to the forthcoming MEPC 70 in October 2016. The draft MEPC circular’s recommendations on the location for fuel oil sampling seem to be in line with the EMSA guidance.