OBQ / ROB Survey During Charter Changes in Valencia, Spain
An OBQ / ROB Survey is an independent technical verification that determines the exact quantity of fuel onboard a vessel during charter delivery and redelivery.
MarineBunkerSurvey.com provides professional OBQ/ROB attendance in Spanish ports to ensure contractual transparency and prevent disputes between shipowners and charterers.
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.
OBQ / ROB Survey
What Is an OBQ / ROB Survey?
An OBQ/ROB survey establishes accurate bunker quantities at key contractual moments:
OBQ (On Board Quantity): quantity of fuel onboard at delivery (start of a charter)
ROB (Remaining On Board): quantity of fuel remaining at redelivery (end of a charter)
These quantities often impact financial settlement, hire calculations, and dispute resolution under charter party terms.
OBQ / ROB Survey
Why OBQ/ROB Matters at Charter Delivery & Redelivery
Fuel onboard is a direct commercial value. Without independent verification, disputes may arise due to:
Differences between declared and measured quantities
Measurement method inconsistencies
Tank table or temperature correction errors
Incomplete or unclear documentation
Operational constraints during tight port schedules
An independent OBQ/ROB survey provides a neutral, auditable determination.
OBQ / ROB Survey
Scope of Attendance (What We Do)
Our OBQ/ROB service may include:
Pre-Measurement Preparation
Review of tank arrangement and access
Verification of applicable tank calibration tables
Establishment of measurement method (ullage/sounding as applicable)
Tank Measurements & Data Recording
Manual and/or electronic tank measurements
Temperature readings
Density determination, where applicable
Clear logging of measurement conditions
Quantity Determination
Volumetric calculations
Temperature correction application
Density and conversion factor application (as required)
Final reconciliation of quantities for OBQ and/or ROB
METHODOLOGY
Calculation Methodology (Transparent and Defensible)
Accuracy depends on a chain of calculations that can be audited.
Our methodology may include:
Measurement recording per tank
Application of calibration tables
Temperature correction and standardisation were required
Density-based conversion for quantity determination
Consolidation into total OBQ/ROB quantities
Clear assumptions and limitations are stated in the report
CASES
Typical Use Cases
OBQ/ROB surveys are typically requested for:
Charter delivery (on-hire) and redelivery (off-hire)
Fleet management bunker reconciliations
Contract handovers involving multiple grades (VLSFO, MGO, etc.)
Dispute prevention prior to hire settlement
Claims support when discrepancies are suspected
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)
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.
REPORT
OBQ / ROB Survey Technical Report
Your report typically includes:
Measurement records per tank
Applied calculations and correction factors
Final OBQ and/or ROB quantities
Fuel grades and relevant observations
Notes on measurement conditions and any anomalies
The report may be used for:
Charter party settlement support
Commercial reconciliation
Dispute prevention and claims documentation
Insurance and P&I review
OBQ / ROB Survey
When Should You Request an OBQ / ROB Survey?
You should consider independent attendance when:
A charter delivery or redelivery is scheduled
There is high fuel value onboard
Multiple fuel grades are involved
Prior discrepancies have occurred
Settlement depends on accurate bunker quantities
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.
When do I need an OBQ/ROB survey?
At charter delivery/redelivery or any handover where fuel quantity impacts settlement between parties.
When is a detective bunker survey required?
When there is a material discrepancy between declared and measured quantities or when procedural anomalies require technical investigation.
Request Attendance / Get a Quote
To confirm availability and quote accurately, please send:
Vessel name + IMO (if available)
Port + ETA/ETB
Fuel grades and expected quantities (MT)
Supply method (barge/shore/truck/STS)
Required service (BQS / OBQ-ROB / Detective)
VALENCIA Marine Services
Camino del Canal 91 Real Club Náutico de Valencia Block 3 Office 21 Valencia 46024 (SPAIN)
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