Bunker Quantity Surveys — Why and When to Appoint One

What a bunker survey is

A bunker quantity survey is an third-party witness to a bunker delivery. The surveyor attends onboard and on the barge, witnesses opening and closing soundings, verifies gauging equipment and procedures, monitors the transfer, supervises sampling, and issues a written report documenting findings and any discrepancies.

Cost versus value

Surveyor fees typically range from a few hundred to low-thousands of dollars per attendance, depending on location and stem size. For a stem of 1,000+ tonnes where even a 0.5% discrepancy represents material value, the survey cost is almost always well-justified. For small stems (say, 50 tonnes of LSMGO), the economics are tighter.

When a survey is particularly valuable

High-value stems (large quantity or premium grades). New supplier relationship without commercial trust history. Port known for quantity disputes. Vessel without modern tank gauging systems. Contracts that require joint survey. Where the stem is disputed or contested before it happens (e.g., known delivery barge history of short delivery).

What a survey cannot do

A surveyor witnesses procedure and records measurements. They cannot determine fuel quality beyond visual observation and basic tests. Laboratory analysis of retained samples is required for quality disputes. They also cannot force commercial parties to agree — they document facts, which then inform commercial resolution.

Choosing a surveyor

Reputable surveyor firms include names known to the bunker industry — SGS, Saybolt, Intertek, Inspectorate, Camin Cargo, and several regional specialists. Independence is critical — the surveyor must not have conflicts with supplier or vessel. Appointment should be made in writing with clear scope and fee basis.

Survey report content

Typical survey report includes: vessel and barge details, personnel present, opening tank inventories on both sides, temperature and density measurements, flow meter readings if applicable, transfer duration and rates, closing tank inventories, calculated quantity, any observed irregularities, and sealed sample details. The report is the basis for commercial settlement if dispute arises.