Fuel oil sampling points become mandatory

The amendments are designed to support procedures for sampling and verification of the sulphur content of fuels and were approved at the IMO’s Marine Environment Protection Committee (MEPC 75) in November 2020.

Three types of fuel oil samples have been defined in MEPC.324(75): in-use, on board, and MARPOL delivered.

Three types of fuel oil samples now defined in MARPOL – in-use sample, onboard sample, and MARPOL delivered sample. Lloyd’s Register explains:

In-use sample: a sample of fuel oil in use on a ship (typically taken downstream of the in-use fuel oil service tank and close to the fuel oil combustion machinery).

Onboard sample: a sample of fuel oil intended to be used or carried for use onboard that ship (a sample of the fuel oil in the fuel oil tank).

MARPOL delivered sample: the sample of fuel oil delivered during the bunker operation (the existing bunker sample requirement).

The requirements apply to vessels 400gt and above. For new ships with keel laid on or after 1 April 2022), they are required on delivery. For existing ships, they are required by the first International Air Pollution Prevention (IAPP) renewal survey undertaken on or after 1 April 2023.

Gard notes that the requirements apply to all fuel oil intended for combustion purposes including that used for main engines, auxiliary engines, incinerators, inert gas generators, boilers, and emergency equipment. They don’t apply to low-flashpoint fuels.

The sampling points are to be clearly marked and easily and safely accessible. They must be located in a position shielded from any heated surface or electrical equipment. The shielding should be sturdy enough to endure leaks, splashes or spray under design pressure of the fuel oil supply line don’t allow fuel oil onto surface or equipment.

Any modification of fuel oil systems and verification of compliance with MARPOL Annex VI must be followed up by a ship’s classification society. Gard notes that plan approval and survey requirements are likely to differ amongst classification societies.

A 95% confidence boundary will be allowed for in-use and onboard sample testing. A sample will be considered acceptable if the test result does not exceed 0.53% sulphur (for the 0.50% limit). However, MARPOL delivered samples must not exceed 0.50% sulphur.

Gard’s insight “Are you 95% confident that your very low sulphur fuel is on spec and MARPOL compliant?” provides additional information on the new test procedures, as well as on some of the dilemmas that may arise from the different verification standards.

More information is available from Gard here.