Mass Flow Meter (MFM)
Bunker surveys with the Mass Flow Meter (MFM)
Since the MFM requirement took effect, more and more bunker barges measure the delivered fuel quantity with a Mass Flow Meter instead of manual gauging. As an independent bunker surveyor, we check these measurements and make sure the documentation, sealing and procedure around the MFM are correct.
Since a few months ago, the use of a Mass Flow Meter (MFM) has been mandatory for bunker deliveries above 300 tonnes in the port of Rotterdam, under the bunker permit issued by the Harbour Master's Division. Antwerp-Bruges has a comparable requirement under the Harbour Police Regulation, article 12.5.4.1.5. Both frameworks refer to ISO 22192, the international standard for mass flow metering systems in bunkering operations.
For permit holders and bunker barges, this means that alongside the physical installation, the correct documentation must be on board and the bunker surveyor must be given access to the system. We know these requirements from daily practice and check them at every delivery.
Documentation we check on board
A fixed set of documents must be on board and up to date for every MFM delivery. We check these before and during the bunkering operation.
- MFM system diagram and sealing points – a diagram of the metering system with all seal locations
- Cargo system piping diagram – an up-to-date piping diagram with valves, bypasses, drain, sampling and stripping points
- Document stating Qmin, Qmax and MMQ – the operational limits approved by the meter manufacturer
- Meter seal verification report and meter zero verification report
- Mass flow metering system seals checklist, meter reading record form and meter totalizer log to ISO 22192
- Bunker Metering Ticket (BMT) and Bunker Delivery Note (BDN) for each delivery
Procedure for quantities below the MMQ or Qmin
If the quantity to be delivered is below the meter's minimum measured quantity (MMQ) or minimum flow rate (Qmin), the MFM is not accurate enough. We guide this exception according to the set procedure.
- Known in advance: a photo of the nameplate showing Qmin/MMQ, written agreement from the receiving vessel and the Bunker Requisition Form are submitted to the port authority beforehand
- Not known in advance: immediate notification to the Harbour Master's Division or Harbour Master Service, with the same documents submitted afterwards
- A surveyor is always present for a delivery below the MMQ; we provide our name and company details to the port authority
Sealing of the MFM installation
All openings between the MFM and the transfer point are sealed to prevent backflow and tampering. We check this operational sealing at every delivery.
- Numbered, tamper-evident seals; every seal is traceable to whoever placed it
- Sealing is carried out by the bunker barge's crew or by an authorised surveyor; our presence is not mandatory but customary
- Any seals we place ourselves are logged in the MFM metering system seals checklist
- Seals may only be broken by the bunker barge's crew, and during an operation only with the knowledge of the bunker surveyor or the receiving vessel's Chief Engineer
Open versus closed measuring (ADN 2025)
ADN 2025 requires closed sampling and measuring for dangerous goods. A transitional arrangement applies to conventional bunker fuels such as gasoil and fuel oil.
- If a bunker barge does not yet have a partly closed sampling device, a manual measurement through the open opening is still allowed until 1 January 2027 – the ILT is temporarily not enforcing this until that date
- If a closed device is present but the tank calibration has not yet been adjusted, the same temporary transitional arrangement applies
- If the sampling device is defective, article 7.2.4.22.8 allows a temporary fallback to an open measurement, provided the defect is recorded in writing or digitally
- Every manual measurement is carried out with calibrated and certified equipment; when we perform this measurement on behalf of the receiver, we bring our own equipment
Our role as bunker surveyor on MFM deliveries
Permit holders are required to facilitate the bunker surveyor. In practice, we request access before, during and after every delivery to:
- The MFM system certificates and tank tables
- The tank radar readings, before and after delivery
- The totalizer data, in both directions
- The sealing checklist and the placing of operational seals
- The data generated by the MFM system, including raw meter data on request
- The piping system, before and after the bunkering operation
Questions about an MFM delivery?
Get in touch — we're happy to help you get the documentation and procedure right.