The introduction of mass flow meters (MFM) for bunker operation in Singapore is a welcome development. Unfortunately it appears that although the equipment has changed, the behaviour of some unscrupulous suppliers has not.

The main objective of supplying bunkers through the MFM was to avoid discrepancies in the quantity of bunker supply.

It has been reported that piping irregularities were discovered on bunker tankers. One implication of such piping fixture irregularities may be that they allow some quantity of bunkers to be siphoned back into the bunker tanker tanks whilst bunkering is in progress. This would mean that the amount registered on the Mass Flow Meter (MFM) total is greater than that delivered to the vessel, with the vessel receiving less than that recorded. Piping fixtures form an integral part of the MFM system, as specified in the Technical Reference for Bunker Mass Flow Metering (TR48). One of the roles of the bunker surveyor is to check the integrity of this system.

Since 1 January 2017, the figure on the Bunker Delivery Note (BDN) presented to the vessel is the figure obtained from the MFM. Bunker barges do not accept figures derived after calculating quantity received on board from soundings, nor do they participate in the sounding process.

Soundings should still be taken on board before and after bunker delivery and, in case of a difference between the vessel figures and the BDN, letters of protest should be issued. Bunker suppliers will not usually accept these letters of protest or will refuse to sign. But in the event of a dispute, they are evidence to show a difference between the MFM figure and the figure obtained by the sounding method. Charterers should be informed of any difference immediately.

The use of a reputable bunker surveyor who can inspect the bunker barge lines for any irregularities in addition to cross checking the seal verification report, inspecting the seals and taking MFM readings, is recommended.