Off-hire bunker ROB discrepancy: 7 steps when owner and charterer figures don't match

Short answer. If the owner’s and charterer’s ROB figures differ at redelivery, act before the vessel sails. Hold the tanks, align both figures by tank, grade, mass, density and time, recheck the calculations, re-gauge the disputed tanks together, compare the result with the ship’s records, and record any unresolved difference in the survey report. Apply the charter party’s pricing terms after that. Most evidence remains available only while the vessel stays at the redelivery point.

Scope. For technical managers, superintendents, masters, chief engineers and charterers’ operators on tankers and dry bulk carriers. It covers ROB disagreements at delivery or redelivery under a time charter. NYPE 2015 and SHELLTIME 4 (2003 edition), Clause 15 as quoted in an English court judgment, serve as reference forms. Your fixture, rider and governing law determine the position. Our bunker survey guide covers measurement method. This guide excludes quality disputes and shortfalls against a supplier’s delivery figure, which Apeks Marine’s bunker quantity survey page covers. This is an operational checklist, not legal advice.

Two meanings of “off-hire”

The term appears in two places, both involving bunkers.

• The off-hire survey is a joint survey before redelivery, at the latest at the last discharging port. NYPE 2015 Clause 5 requires joint on-hire and off-hire surveys “for the purpose of ascertaining the quantity of bunkers on board and the condition of the Vessel”.
• An off-hire period under Clause 17 is time lost through breakdown, detention or a similar cause, during which hire stops. Clause 17 places all bunkers used while off-hire on owners’ account.

A redelivery ROB dispute can involve an off-hire period. Fuel burned during a breakdown is part of the consumption record that the surveyors reconcile, and it is counted there once.

What the charter party has already decided

Read these clauses before discussing a tonne.

Question	NYPE 2015	Where to look if you use another form
Who surveys	Each party appoints a surveyor at its own cost; a joint survey produces one report signed by each surveyor, with separate reports permitted for disputed items (Clause 5)	Survey or on/off-hire clause
Non-attendance	The absent party is bound by the other party’s report (Clause 5)	Same clause; check the rider
Survey time	Charterers bear time lost on the off-hire survey (Clause 5)	NYPE 93 put it on owners’ time
Who buys the ROB	Charterers on delivery and owners on redelivery take over and pay for all bunkers remaining on board (Clause 9(a)(i))	SHELLTIME 4 Clause 15: owners pay for bunkers remaining on board at redelivery
Price	The parties enter it in 9(a)(i), or use the net contract price paid, evidenced by invoice, under 9(a)(iii)	SHELLTIME 4 (2003 edition) Clause 15: price actually paid, first-in-first-out, supported by paid invoices; the court read “price actually paid” as the price paid when the bunkers were stemmed
Quantity on redelivery	”Unless agreed otherwise”, same grades and “about the same quantities” as on delivery, always appropriate and sufficient to allow the Vessel to reach safely the nearest port with fuels of the required types (Clause 9(g)); 9(a)(iii) uses similar words	BIMCO Types and Quantities of Bunkers on Redelivery Clause 2011 has the same structure and also opens with “Unless agreed otherwise”
Deduction	Unless option 9(a)(ii) or (iii) applies, charterers may deduct redelivery-bunker value from the last sufficient hire payment(s); parties settle any hire and bunker difference within five Banking Days after redelivery (Clause 11(e))	Hire payment clause
Logs	The master keeps full and correct deck and engine logs and supplies true copies showing bunker consumption when required (Clause 15)	Logs clause

The printed NYPE 2015 text gives no number for “about the same quantities”. Clause 9(g) opens with “Unless agreed otherwise”, and Clause 9(a)(i) leaves a blank for “bunker quantities and prices on delivery/redelivery”. The BIMCO 2011 clause opens with the same words. BIMCO’s notes say its bunker clause suite is not meant to deal with the actual pricing or quantities of bunkers, which the charter party already covers, and warn users to make sure added clauses do not conflict with existing ones. How a figure in the 9(a)(i) blank, a rider quantity clause and the printed 9(g) wording work together depends on the drafting of each charter. Read the recap, the rider and the printed form side by side for every fixture, and take legal advice where they point in different directions.

Where the Clause 11(e) deduction applies, it comes off the last hire payment(s), which can fall due while the vessel is still on her way to redelivery. The figure deducted may therefore be an estimate made before the off-hire survey.

The 7 steps

1. Hold the tanks before you argue

As soon as two figures appear, stop activities that alter them.

• Do not transfer fuel between bunker tanks until the parties settle the figures. If operations require a transfer, log its time, tanks and quantity.
• Record each measurement in ship’s time and state the UTC offset in force. Consumption between measurement times creates a gap even where both sides measured without error.
• Record draughts, trim and list at gauging. The calibration tables require them.
• Keep both surveyors on board until step 6 ends, if the redelivery schedule permits.

2. Put both figures on one basis

Request each figure by tank and grade, then place them side by side. Comparing totals hides the cause.

Column	Why it matters
Tank and grade	A gap in one tank points to measurement; a gap across tanks points to density or basis
Observed sounding or ullage	Shows whether both sides read the same level
Trim and list correction applied	Different corrections change volume from the same reading
Observed temperature	Sets the volume correction
Density at 15 °C used, and its source	A BDN figure, laboratory result or assumed grade value produces different masses
Mass basis	Weight in air and weight in vacuum differ; both sides need the same basis
Time of measurement	Shows consumption hours between readings
Tanks included	Shows settling, service, overflow and drain tanks included by one side and omitted by the other

If the difference closes at this stage, the parties used different bases. The remainder is a measured difference.

3. Re-run the arithmetic line by line

Start with the tank showing the largest gap. Check that both sides used the vessel’s current calibration tables, the same trim and list correction, and the same volume correction factor for the density. Our bunker quantity calculator calculates the observed-volume-to-VCF-to-mass chain in the browser and shows each step. It starts with volume corrected for trim and list and does not model tank geometry. The bunker survey guide gives the full method from sounding to tonnes.

Check for a transposed density, superseded calibration table or wrong trim entry before requesting a re-gauge. Those checks take minutes.

4. Re-gauge together while the ship is still there

If the calculations agree but readings differ, measure again together. Apeks Marine’s on/off-hire survey guide describes joint attendance; the following points decide a disputed tank.

• Re-gauge disputed tanks with both surveyors and the chief engineer present.
• Cross-check a remote gauge with a manual sounding where tank arrangement and the safety regime permit.
• Take temperature at more than one depth in heated tanks.
• Dip for water and record free water and sludge on lines separate from fuel.
• Record any tank that cannot be measured with confidence as a limitation and give the reason. A report that presents an estimate as a measurement weakens the whole record.

After sailing, consumption changes each tank and parties cannot measure the redelivery ROB again. The written survey record then carries the evidence.

5. Reconcile against the ship’s own records

The ship maintains a running fuel account, and the redelivery figure must fit it. Use one formula, per grade:

Expected redelivery ROB = delivery ROB + bunkers received during the charter − total fuel consumed from delivery to redelivery

Line	Source	In the formula
Delivery ROB	On-hire survey report	Add
Bunkers received during the charter	Bunker delivery notes and Oil Record Book Part I code H entries	Add
Total fuel consumed, delivery to redelivery, off-hire periods included	Noon reports and engine log	Subtract once
Fuel used during each off-hire period	Engine log for the off-hire period	Do not subtract again; it is already inside total consumption. Keep it for the hire statement in step 7

• Bunkering records. IMO guidance on Oil Record Book entries, MEPC.1/Circ.736/Rev.2, records each bunkering under code H by grade and total quantity in metric tonnes, with the quantity added to each tank and that tank’s resulting content. Inspectors also check for an accurate Oil Record Book, as our review of engine-room inspection risks explains.
• Consumption records. NYPE 2015 Clause 15 requires the master to keep full and correct deck and engine logs and to supply true copies showing bunker consumption when charterers require them.
• Off-hire fuel. Clause 17 decides who pays for fuel used while off-hire. It does not change how much fuel is left in the tanks.

If the measured figure differs from the expected figure, the technical manager needs to examine consumption reporting, a tank omitted from daily soundings, or a calibration problem before the commercial discussion.

6. Put the disagreement in the survey record

If steps 2 to 5 leave a gap, record it before attendance closes.

• NYPE 2015 Clause 5 requires one report signed by each surveyor and preserves each surveyor’s right to file a separate report on disputed items. Use it. Signing a disputed figure without a record leaves your side arguing against its own document.
• The master or chief engineer issues a letter of protest stating both figures by grade, the ship’s supporting measurements, measurement times and recorded limitations.
• Under the printed Clause 5, non-attendance binds your side to the other party’s report. Send a representative or record written acceptance of the other report.
• Keep sounding sheets, temperatures, densities and their sources, calculation sheets, gauge photographs and the step 5 reconciliation together.

7. Let the charter party price the difference, then settle

Convert tonnes into money after the evidence is fixed.

• Identify the fixture’s bunker option: NYPE 2015 9(a)(i) with agreed prices, 9(a)(iii) with invoice prices, or a tanker form such as SHELLTIME 4 (2003 edition) Clause 15 using price actually paid on a first-in-first-out basis supported by paid invoices.
• Check the last hire statement. Unless option 9(a)(ii) or (iii) applies, charterers may deduct redelivery-bunker value from the last sufficient hire payment(s); parties settle any hire and bunker difference within five Banking Days after redelivery under Clause 11(e). The deduction may already use an estimate.
• If an off-hire period occurred during the charter, the hire statement carries two money items for it: hire that stopped for the time lost, and the value of bunkers used while off-hire, which Clause 17 places on owners’ account. Both are money items, usually settled in the hire statement; the printed clause does not set the netting method. Neither changes the measured redelivery ROB in tonnes.

The off-hire and bunker settlement calculator on apeks.net calculates off-hire time to the minute with each UTC offset, hire for that period, fuel used while off-hire, and the bunker difference by grade in tonnes and dollars. It does not determine off-hire status, the applicable price or netting against hire. The charter party determines those points.

What it means for the operator

For the technical manager and superintendent. The redelivery ROB starts with the ship’s figure. If the chief engineer’s daily soundings and ORB do not support it, the commercial team negotiates from a weak record. Run the step 5 reconciliation a few days before redelivery, while the crew can correct a sounding practice or tank table.

For the master and chief engineer. Your signature on the joint report and your letter of protest provide evidence. Record limitations and times with the UTC offset. Keep transfers stopped until surveyors finish.

For the charterer’s operator. Unless option 9(a)(ii) or (iii) applies, charterers may deduct redelivery-bunker value from the last sufficient hire payment(s), and parties settle any hire and bunker difference within five Banking Days after redelivery under Clause 11(e). Your estimate sets the deduction. Base it on the latest tank-by-tank figures from the ship and expect an adjustment once the joint report is issued. The same division between contract and regulation applies to EU ETS allowances, which the owner-or-charterer ETS tool explains.

For records beyond the charter. The same tank figures feed emissions monitoring. Under Regulation (EU) 2015/757, Annex I, Method A combines BDNs with periodic stocktakes of fuel tanks; the European Commission’s fuel monitoring guidance notes that ships using Method A still need to measure fuel in tanks to make the balance. A ROB figure corrected in the commercial settlement but left unchanged in monitoring records produces two versions of the same fuel.

Checklist to print

• Internal transfers stopped; any forced transfer logged
• Measurement times recorded in ship’s time with the UTC offset
• Draughts, trim and list recorded at gauging
• Both figures shown tank by tank and grade by grade
• Same density source, mass basis (air or vacuum) and tanks included
• Current calibration tables confirmed; arithmetic re-run for the largest gap
• Disputed tanks re-gauged jointly; water and sludge recorded on separate lines
• Unmeasurable tanks recorded as limitations with the reason
• Reconciliation per grade: delivery ROB + received (BDN, ORB code H) − total consumed (logs, off-hire periods included)
• Off-hire fuel listed separately for the hire statement only, not subtracted a second time
• Separate report on disputed items; letter of protest with both figures
• Bunker option, price basis and any quantity provision identified in the recap, rider and printed form
• Last hire statement checked for a Clause 11(e) deduction
• Settlement arithmetic shared with the other side step by step

Next step

Use the off-hire and bunker settlement calculator to check settlement arithmetic against your figures. Apeks Marine provides a joint on/off-hire bunker and condition survey for vessels in Türkiye if both parties prefer a single independent figure at delivery and redelivery. According to Apeks Marine’s own figures, the company, which is part of the same group as Apeks Tech, attends 100–120 off-hire bunker surveys a year and identifies over 3,500 MT of fuel quantity discrepancies across those attendances (company figure).