Independent Bunker Surveyor in Spain (BQS • OBQ/ROB • Detective Surveys)
VALENCIA Marine Services provides independent bunker quantity verification for merchant vessels operating in Spain.
We attend bunkering and charter change operations to deliver evidence-grade measurements and calculations that reduce disputes and protect commercial interests
Bunker Quantity Survey (BQS)
Quantity delivered/received verification
OBQ / ROB surveys
Charter change transparency and contract protection
Detective Surveys
Investigation of shortages, procedures, and discrepancies
SERVICES
Bunker Survey Services in Spain
Bunker Quantity Survey (BQS)
OBQ / ROB Survey During Charter Changes
Detective Survey for Bunker Supply Discrepancies
Need attendance fast? We operate with rapid mobilisation for port operations and time-critical schedules
Bunker Quantity Survey (BQS)
OBQ / ROB Survey During Charter Changes
Detective Survey for Bunker Supply Discrepancies
A Bunker Quantity Survey (BQS) determines the actual quantity of fuel delivered onboard through independent technical verification.
Our BQS typically includes:
Tank measurements before and after supply (ship and/or barge/shore, as applicable)
Volumetric calculations with temperature correction
Verification of tank calibration tables
Density control and application of conversion factors (e.g., to a standard reference)
Supervision of fuel transfer operations
Cross-checks against nomination and Bunker Delivery Note (BDN)
Objective: prevent financial losses and contractual disputes by validating the true received quantity.
During a charter change, quantity determination is critical:
ROB (Remaining On Board): fuel remaining at the end of the contract
OBQ (On Board Quantity): quantity onboard at delivery into the new charter
Why it matters: OBQ/ROB disputes create immediate commercial friction between charterers and owners. Independent measurement ensures contractual clarity.
A Detective Survey is performed when there is a significant gap between declared and measured quantities.
The assessment may include:
Review of bunkering procedures and operational steps
Inspection of pipelines, valves, and manifold arrangements (as accessible)
Review of records (logbook entries, timing, transfer documentation)
Technical evaluation of potential losses, measurement errors, or irregularities
Use case: shortage claims, charter party disputes, and insurance / P&I documentation.
SERVICE
Applied Technical Methodology (What makes the numbers defensible)
Calculations
Fuel density determination and corrected quantity computation. Verification of tank tables and measurement conditions
Tanks
Fuel density determination and corrected quantity computation. Verification of tank tables and measurement conditions
Reconciliation
Clear reconciliation between measured results and supplied documentation
OUR VESSELS
Vessel Types We Support
Tankers
Oil tankers, Chemical Tankers, Gas Carriers
Containers
All Sizes
Merchant
Multipurpose ships, Ro-Ro Units, Others
Bulk Carriers
All types
PAX
Ferries and Cruise Ships
Yachts
Large Yachts & Specialised Units
OUR REPORTS
Bunker Survey Technical Report (Evidence-grade deliverable)
Technical Evidence
Pre/post measurements, calculations and corrections factors, observation and anomalies, quantities, photographic supports
Designed for
Owners, charters, traders, P&I Clubs, and insurers
Electronic
PDF format, downloadable.
OUR MAIN OPERATIONS PORTS
Coverage in Spain (Ports)
We attend operations across Spain depending on schedule and access, including major commercial ports such as:
01
VALENCIA
Base Port, Includes Valencia Port, Sagunto Port ang Gandia Port
02
CASTELLÓN
Castellón Port, Burriana Port, Vinarós Port
03
ALICANTE
Alicante Port, Santa Pola Port, Tabaerca port, Torrevieja Port
04
TARRAGONA
Tarragona port, Sant carles de la Rápita
05
BARCELONA
Barcelona Port, Vilanoba i la Geltrú port.
06
CARTAGENA
Cartagena Port.
OUR CUSTOMERS
Who We Work For?
We typically act for:
A Shipowners & operators
Charterers
Bunker traders / fuel suppliers (independent verification when required)
P&I Clubs
Marine insurers
Law firms and claims teams
FAQs
Everything you need to know now
What is a Bunker Quantity Survey (BQS)?
A BQS is an independent survey that determines the actual fuel quantity delivered and received by measuring tanks before and after supply and applying correction calculations.
When do I need an OBQ/ROB survey?
At charter delivery/redelivery or any contract handover where fuel quantities impact commercial settlement between parties.
What triggers a detective bunker survey
When the quantity on the BDN or declared onboard differs materially from measurements—or when procedures suggest potential loss, error, or irregularity.
Can your report be used for claims?
Yes—the report is structured as technical evidence with a transparent calculation trail and observations
Request Attendance / Get a Quote
Send Send:
Vessel name + IMO (if available)
Port + ETA/ETB
Fuel grades and expected quantities
Supply method (barge/shore
Required service (BQS / OBQ-ROB / Detective
CTA: Email / WhatsApp / Call (24/7 ops)
VALENCIA Marine Services
Camino del Canal 91
Real Club Náutico de Valencia Block 3 Office 21 Valencia (Spain)
MarineBunkerSurvey.com
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