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Detective Bunker Survey (Fuel Discrepancies & Claims Support) in Valencia, Spain

A Detective Bunker Survey is a structured technical investigation conducted when discrepancies arise between declared bunker quantities and measured fuel onboard.

VALENCIA Marine Services provides independent investigative bunker survey services in Spanish ports to support commercial disputes, charter party claims and insurance matters.

Bunker Quantity Survey (BQS)

A Bunker Quantity Survey (BQS) is an independent verification process that determines the actual quantity of marine fuel delivered and received onboard a vessel through structured measurement and calculation procedures.

OBQ / ROB Survey (Charter Delivery & Redelivery)

An OBQ / ROB Survey establishes the precise quantity of fuel onboard a vessel at charter delivery or redelivery, ensuring contractual transparency between shipowners and charterers.

Detective Bunker Survey (Fuel Discrepancies & Claims Support)

A Detective Bunker Survey is a technical investigation conducted when discrepancies arise between declared and measured fuel quantities, providing structured analysis and documentation for commercial or insurance claims.

Detective Bunker Survey

What Is a Detective Bunker Survey?

A detective bunker survey is performed when:

There is a material difference between the declared BDN quantity and the onboard measurement
A shortage is suspected
Operational irregularities are observed
Documentation inconsistencies exist
A dispute between the owner, charterer, or supplier arises

The objective is to determine, document and technically analyse potential causes.

Detective Bunker Survey

Typical Discrepancy Scenarios

Detective surveys are commonly requested in cases involving:

Quantity shortages
Unexpected ROB differences at charter redelivery
BDN inconsistencies
Measurement methodology disputes
Suspected procedural deviations
Operational irregularities during bunkering

Detective Bunker Survey

Scope of Investigation

Depending on operational access and circumstances, the investigation may include:

Documentation Review

Bunker Delivery Notes (BDN)
Measurement logs
Operational timeline records
Charter party clauses relevant to fuel settlement

Technical Assessment

Re-measurement of bunker tanks (where feasible)
Verification of calibration tables
Review of temperature and density data
Volumetric recalculation
Analysis of the correction factor application

Operational Review

Inspection of accessible pipelines and manifold arrangements
Review of transfer procedures
Assessment of potential measurement or handling errors

METHODOLOGY

Structured Analytical Approach

The investigation focuses on:

Identifying calculation inconsistencies
Evaluating measurement methodology
Determining potential sources of quantity variance
Assessing whether discrepancies fall within a reasonable tolerance

All findings are documented clearly and objectively.

CASES

When Should You Request a Detective Bunker Survey?

Independent investigative attendance is recommended when:

A shortage claim is being considered
Charter redelivery fuel quantities are disputed
There is financial exposure linked to fuel quantities
Parties require a neutral third-party technical evaluation
Insurers or P&I Clubs request structured documentation

VESSELS

Services by Vessel Type

This service is primarily provided for:

Merchant vessels and commercial units
Tankers
Container ships
Bulk carriers
Ferries
Large yachts & specialised units (case-by-case, high-value operations)

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PORTS

Ports Covered in Spain (Mediterranean)

We attend bunker operations across Spanish Mediterranean ports, including:

Mediterranean Ports

Barcelona
Tarragona
Castellón
Valencia
Alicante
Cartagena

Other Ports

Attendance at other Spanish ports may be arranged upon request, depending on logistics and schedule.

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REPORT

Detective Bunker Survey Technical Report

The final report may include:

Measurement findings
Calculation review and reconciliation
Identification of discrepancies
Technical observations
Analytical conclusions based on available data
Supporting documentation references

The report may be used for:

Commercial negotiations
Charter dispute resolution
Insurance review
Claims documentation

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FAQs

Everything you need to know now

What is a Bunker Quantity Survey (BQS)?

An independent verification of delivered/received fuel quantity based on tank measurements before and after supply and corrected volumetric calculations.