Technical Circular No: 061/2022

Subject: MARPOL requirements on In-use sampling point.

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1. The amendment to MARPOL Annex VI related to fuel oil sampling and verification procedures for the sulphur content of fuel oil were adopted by Resolution MEPC.324 (75). The amendment introduced requirement of two new fuel oil samples for confirming compliance with MARPOL Annex VI sulphur requirements, namely the “in-use sample” and On-board sample”.

On board Sample: On board sample means a sample of fuel oil intended to be used or carried for use on board that ship.

In-use sample: In-use sample means a sample of fuel oil in use on a ship.

2. In- use sampling point(s) is to be fitted or designated for the purpose of taking representative samples of the fuel oil being used on board the ship taking into account “2019 Guidelines for onboard Sampling for the Verification of the Sulphur Content of the Fuel Oil Used on board Ships (MEPC.1/Circ.864/ Rev.01)”. The sampling point meant to take in-use sample to represent fuel oil in use at the time and for which sampling point is designated.

3. Application of the requirement:

a. Applicable to the fuel oil supply systems for all new and existing ships of 400 GT and above engaged on international voyages as well as all fixed or floating drilling rigs and other platforms. This applies to all fuel oil intended for combustion purposes for both propulsion and on-board operations, meaning that all fuel oil systems serving main engines, auxiliary engines, boilers, incinerators, IG generators, emergency equipment and other consumers shall be fitted with designated sampling points. The requirements are not applicable to a fuel oil service system for low-flashpoint fuel having a flashpoint less than 60°C.

b. New ships:  For ships with keel laid or which is at a similar stage of construction on or after 1 April 2022

c. Existing Ships:  For ships the keel of which is laid or which is at a similar stage of construction before 1 April 2022, the first IAPP renewal survey carried out on or after 1 April 2023.

4. Action required by ship Owners/ Managers:

a. Where existing sampling points meeting the requirement of MEPC.1/Circ.864/Rev.1 are available, the same may be designated as in- use sampling points. If not, new sampling points are to be fitted.

b. Proposal for fitting or designating in-use sampling points is to be submitted for consideration of IRS.

5. The requirements for fitting or designating in-use sampling points:

a. Fuel oil sampling points are required to be fitted or designated for the purpose of taking representative samples of the fuel oil being used on board the ship, taking into account MEPC.1/Circ.864/Rev.1.

b. The requirements for sampling points required by MEPC.1/Circ.864/Rev.1 are as follows:

1) be easily and safely accessible;

2) take into account different fuel oil grades being used for the fuel oil combustion machinery item;

3) be downstream of the in-use fuel oil service tank;

4) be as close to the fuel oil combustion machinery as safely feasible taking into account the type of fuel oil, flow-rate, temperature, and pressure behind the selected sampling point;

5) be clearly marked for easy identification and described in either the piping diagram or other relevant documents;

6) each sampling point should be located in a position shielded from any heated surface or electrical equipment and the shielding device or construction should be sturdy enough to endure leaks, splashes or spray under design pressure of the fuel oil supply line so as to preclude impingement of fuel oil onto such surface or equipment; and

7) the sampling arrangement should be provided with suitable drainage to the drain tank or other safe location.

6. The design requirements for fitting new in-use sampling point:

a. The design and location of sampling point is to enable samples of fuel oil to be taken easily and in a safe manner.

b. The position of a sampling point is to be such that the sample of the fuel oil is representative of the fuel oil quality at its location within the system e.g. by ensuring steady state flow past the sampling point.

c. The sampling points are to be provided with a shut-off valve and a self-closing valve.

d. The pipes and their valves and fittings are to be of steel or other approved material. Ordinary cast iron valves may be used in piping system where the design pressure is lower than 7 bar and the design temperature is below 60°C

e. The pipes conveying oil heated above 60°C are to be of seamless steel or other approved material having flanged or welded joints.

f. The materials used for pipes are to comply with recognized standards. The materials used for pipes of Class I & II are to be IRS Certified.

g. Pressure ratings of flanges/valves are not be lower than the maximum working pressure of the FO system, and not to be lower than 14 bar for fuel oil systems with working pressure above 7 bar & a working temperature above 60°C and other fuel oil system not to be lower than 3 bar.

h. Pipe thickness are not be less than as required by IRS Rules Pt.4, Ch.2, Section 1.

i. Drip trays are to be arranged below the sampling points to ensure suitable drainage to a drain tank or other safe location.

j. After installation a function test is to be carried out.

7. Ship Owners / managers and masters are advised to be guided by above and accordingly plan for the fitting or designating of sampling points as required by revised MARPOL Annex VI, Reg. 14.

8. IRS HO may be contacted for further guidance in this regard.



This Technical Circular and the material contained in it is provided only for the purpose of supplying current information to the reader and not as an advice to be relied upon by any person. While we have taken utmost care to be as factual as possible, readers/ users are advised to verify the exact text and content of the Regulation from the original source/ issuing Authority. 

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