Learning objectives
- Describe the sulphur limits applicable to marine fuels and the relevant Emission Control Areas (ECAs).
- Safely conduct or supervise a bunkering operation.
- Manage fuel sampling and quality verification.
- Carry out and check a bunker survey, from volume measurement to metric tonnes.
- Handle a commercial dispute over fuel quality or quantity.
- Identify fuel consumption optimisation levers.
- Understand the management implications of the transition to alternative fuels.
- Place the cost of carbon — EU ETS and FuelEU Maritime — within procurement decisions.
The regulatory framework on sulphur limits
Module objectiveRecognise what Regulation 14 of MARPOL Annex VI requires on sulphur content and in which distinct ways a ship can be compliant.
Limits, ECAs and compliance
The global limit is 0.50% m/m and the ECA limit 0.10% m/m. The Mediterranean has applied since 1 May 2025; Canadian Arctic and Norwegian Sea requirements apply from 1 March 2027; the North-East Atlantic enters into force on 1 September 2027 with operational effect in 2028.
The carriage ban concerns non-compliant fuel carried for use. Residues and fuel not intended for use must be classified and documented; there is no indiscriminate discharge rule for every residue.
An EGCS is an equivalent method only when approved, monitored and managed under applicable conditions, including local washwater restrictions.
Key takeaways
- The sulphur ECAs are not four but five and will become eight: in the Mediterranean the limit applies from 1 May 2025.
- The carriage ban prohibits carrying non-compliant fuel for use, not merely burning it: the residue is fuel to be discharged.
- The FONAR under Regulation 18.2 is a self-declaration of breach, not an exemption, and must be preceded by evidence of best effort.
Planning the bunkering operation
Module objectiveRecognise the eight stages of a bunkering operation and the role of the pre-bunker meeting as the foundation of the entire operation's safety.
The transfer plan
Before connection, verify tank plan, capacity and maximum filling limits, compatibility, segregation, tank sequence, valve line-up, rate and pressure.
Ship and supplier agree communications, emergency stop, slow-down/stop criteria, responsibilities, SIMOPS, weather and relative movement.
Monitoring continues through draining, disconnection, final measurements, BDN, samples, records and discrepancy management.
Key takeaways
- A well-planned bunkering operation reduces the risk of spills, commercial disputes and operational delays.
- The meeting with the supplier before transfer sets roles, responsibilities, emergency procedures and communication arrangements.
- Skipping or shortening the pre-bunker meeting exposes the operation to risks disproportionate to the time actually saved.
Safety during bunkering
Monitoring and stop criteria
Qualified personnel continuously attend the stations designated by the plan; no universal formula requires everyone to remain only at the connection point.
Levels, vents and overflow, manifold, rate and pressure, moorings, scuppers, containment, lighting and communications are monitored together.
Leakage, loss of communication, alarm, abnormal pressure or exceeded limits trigger slow-down or stop under procedure.
Sampling and quality verification
Module objectiveDistinguish the three samples of MARPOL Annex VI and recognise by which test the result of each one is judged.
Three samples, two procedures
The delivered sample already existed; MEPC.324(75) formalised definitions and procedures for in-use and onboard samples and their sampling points.
Appendix VI Part 1 verifies the delivered sample using the mean of two valid subsamples; Part 2 applies limit plus 0.59R to in-use/onboard samples as an analytical decision rule, not a ship margin.
Systems serving only low-flashpoint or gas fuel fall within Regulation 14.12 exclusions. Sampling, sealing, custody, laboratory and retention remain traceable.
Key takeaways
- The delivered sample is drawn at the receiving ship's manifold, by a continuous method throughout the transfer.
- The delivered sample is judged with no margin, while the 95% confidence interval applies to the in-use and onboard samples.
- «In-use» sampling points are a modification to the installation, one that belongs in the maintenance plan, not a procedure.
The Bunker Delivery Note and documentation
Module objectiveRecognise what the Bunker Delivery Note records about a fuel delivery and why it should be checked before signing, not after.
BDN, flashpoint and retention
The oil-fuel BDN minimum content is in Appendix V. Since 1 May 2024 it includes measured flashpoint or a statement that it is at least 70°C under MEPC.362(79).
MEPC.385(81), in force from 1 August 2025, introduces a specific BDN regime for low-flashpoint and gas fuel.
Retain the BDN for three years and the delivered sample for at least twelve months. The seal number supports sample traceability but is not a mandatory Appendix V field.
Key takeaways
- The BDN’s minimum content is not a list of good intentions: Appendix V of MARPOL Annex VI fixes it.
- A declaration signed by the supplier’s representative attests that the fuel supplied conforms to Regulations 14 and 18.
- The BDN is kept on board for three years and the delivered sample for twelve months: two different periods.
Quantity: measuring, comparing, protesting
Module objectiveVerify the quantity of fuel received, recognise where the tonnes go missing and know what is worth protesting.
Tank gauging and MFM
Tank gauging uses sounding/ullage, temperature, tank table, trim/list and density: document method, measurement points and uncertainty.
An MFM reduces conversions but is not immune to air, configuration, zero drift, bypass or anomalies. Check certification, totaliser, events and applicable parameters.
There is no universal four-measurement rule, mandatory one-hour settling time or protest wording that automatically shifts burden of proof. Contract and port standard govern.
Key takeaways
- The bunker survey is four sets of measurements: the ship’s and the barge’s tanks, before and after the transfer.
- Tank volume becomes invoiced mass through the Volume Correction Factor at 15 °C and the air buoyancy correction.
- The Letter of Protest is issued before the barge lets go, stating the discrepancy in figures and its declared origin.
Managing quality disputes
Module objectiveRecognise the signs of off-specification fuel and handle the dispute as a structured process, with ISO 8217 as the reference.
Off-spec and off-quality
The order or contract must incorporate the ISO 8217 edition, grade and additional limits. Families and limits vary and should not be reduced to one universal classification.
MARPOL and commercial samples have different purposes and chains of custody; each may matter in its context.
Segregate suspect fuel, notify, preserve samples and records, then assess safety impact, causal link, notice and mitigation. Clause 5 does not automatically decide the claim.
Key takeaways
- A fuel can meet every numerical parameter and still be unusable: Clause 5.2 covers precisely that case.
- Between the 40 and 60 mg/kg of aluminium and silicon at delivery and the roughly 15 at the engine inlet lies shipboard treatment.
- The more time passes before the challenge is formalised with a Letter of Protest, the weaker the ship's position becomes.
Fuel consumption optimisation
Module objectiveRecognise the operational levers that reduce fuel consumption and what each of them acts on.
Measure distinct phenomena
Tonnes/day measures absolute consumption, tonnes/nm normalises distance and g/kWh describes engine efficiency; EEOI and CII include transport work or capacity proxies.
Each comparison accompanies fuel and distance with speed, draft, weather, fouling, power, operating mode and period.
Reducing fuel and energy can lower ETS emissions and affect FuelEU compliance balance and penalty exposure, even though unchanged fuel mix does not automatically change gCO2eq/MJ intensity.
Key takeaways
- Consumption optimisation is part of fuel management and has a direct impact on operating costs and CII performance.
- Slow steaming reduces consumption per unit of distance and is the operational lever with the greatest impact.
- Hull and propeller cleaning reduces hydrodynamic resistance and optimal trim improves propulsive efficiency.
Onboard stock management
ROB, compatibility and risk
Measured ROB, measurement uncertainty, unpumpable/unusable quantity, minimum stock and safety reserve are different quantities.
New bunkers remain segregated until compatibility, analysis and the use plan permit commingling.
Procurement compares price with useful energy, quality, treatment loss, carbon exposure, supplier reliability and operational risk.
The transition to alternative fuels
Module objectiveRecognise what changes in fuel management when the fleet diversifies its fuel sources, from bunkering procedures to dual-fuel competencies.
One plan for each fuel
SOLAS II-1 Part G and the IGF Code form the general framework; detailed provisions and interim guidelines vary for LNG, alcohol fuels, LPG, ammonia, hydrogen and low-flashpoint oil.
Toxicity, flammability, cryogenics, material compatibility, ventilation, detection, PPE, exclusion zones and emergency response require fuel-specific risk assessment and bunkering plans.
STCW V/3 is not a generic certificate for every fuel. In 2026, fuel-specific training guidance for alcohol fuels and ammonia also applies according to ship, role and operation.
Key takeaways
- Each fuel already has its regime: the IGF Code, interim guidelines for methanol and ammonia, ISO 20519 for LNG.
- Bunkering infrastructure for alternative fuels is still limited, and that constrains route planning.
- Those who handle HFO or VLSFO are not automatically ready for methanol or ammonia: specific training is necessary, not optional.
The cost of carbon: ETS, FuelEU and what the IMO still lacks
Module objectiveNavigate the cost of carbon on marine fuel: ETS allowances, the FuelEU trajectory and the state of the IMO framework.
Two compliance architectures
EU ETS: 40% of 2024 emissions, 70% of 2025 and 100% from 2026, surrendered in the following year; CH4 and N2O enter from reporting year 2026.
ETS scope is generally 100% intra-EEA and in port and 50% EEA–extra EEA, subject to port-call definitions, exclusions and derogations. FuelEU instead uses annual well-to-wake intensity, compliance balance and its own flexibilities.
At August 2026 no global IMO pricing mechanism has been adopted. Regional, national, port, tax and contractual regimes still require checking.
Key takeaways
- Since 2024 the company surrenders allowances for 40% of verified emissions, 70% in 2025 and 100% from 2026.
- The ETS puts a price on the quantity of emissions, FuelEU a limit on intensity: against FuelEU, burning less does not help.
- The Net-Zero Framework has not been adopted: the decision is deferred to the extraordinary session of 4 December 2026.
The role of fuel management in the chartering relationship
Module objectiveRecognise why fuel decisions concern the commercial side too and require explicit coordination between functions.
Contractual allocation
Speed warranty, weather criteria, slow steaming, due despatch and CII cooperation are read together: there is no automatic conflict between warranted speed and CII.
The charter should allocate quality, quantity, sampling, notices, claims, ROB and redelivery, including data and decision times.
ETS allowances and FuelEU compliance balance, costs and data need dedicated clauses; commercial allocation does not change the regulated entity.
Key takeaways
- Guaranteed speed clauses in the charter party can conflict with slow steaming decided for CII compliance.
- Disputes over declared versus actual consumption are a common source of contention with charterers.
- Fuel choice is not cost-neutral: it has a direct impact on OPEX costs.
Fuel management KPIs
Module objectiveRecognise the KPIs that make up a fuel management dashboard, how they are calculated and why each one matters.
An actionable dashboard
Each KPI states definition, unit, period, baseline, normalisation, source, uncertainty and action owner.
Quantity discrepancy and quality rate are segmented by method, supplier, port, grade and conditions; otherwise they mix different causes.
CII is a shared outcome of ship and commercial decisions, not the fuel manager’s exclusive KPI.
Key takeaways
- Specific consumption is comparable only between similar ships in similar conditions: without normalisation it says nothing.
- Quantity shortfall is the KPI most often missing, and the one that pays for itself first.
- The fleet CII rating links fuel management to environmental compliance and, for ships trading in Europe, to the cost of allowances.
Emerging trends
Current, interim, proposed
Real-time data and digital BDNs add value only with calibration, data quality, cybersecurity and governance.
Multi-fuel operation multiplies interfaces, compatibility checks, training, spare strategy and documentary evidence.
Label each development as in force, future operational date, interim guidance or unadopted proposal; the IMO Net-Zero framework remains under monitoring.
Recurring mistakes
From the Mistake Library of SuperbaKnowledge, filtered to the subjects this course covers. This view selects and organises content published in SuperbaKnowledge; it does not modify or replace it. The linked Knowledge page remains the reference version, while official texts remain authoritative.
| Topic | Mistake | Typical consequence | Topic sheet |
|---|---|---|---|
| Bunker Delivery Note | MARPOL sample not taken, or taken without a traceable procedure | Unable to prove fuel compliance in a subsequent check | See the topic sheet |
| Bunkering Operations and Fuel Quality Control | Pre-bunkering safety checklist completed as a formality without genuine verification of conditions | Spill risk not adequately mitigated | See the topic sheet |
| North-East Atlantic ECA | Passage planning and chart updates postponed close to the entry-into-force date (1 September 2027) | Risk of sailing in the new ECA without properly planned changeover procedures | See the topic sheet |
| Ammonia Engines | Crew training on alternative fuels treated generically, without distinguishing the specific protocols for ammonia's toxicity | Inadequate response in the event of release or exposure, given the different risk profile | See the topic sheet |
| New 2026 ECAs: Canadian Arctic and Norwegian Sea | The two new ECAs (Canadian Arctic and Norwegian Sea) confused with the future North-East Atlantic ECA, treating them as a single 2027 deadline | Non-compliant navigation in Arctic/Norwegian waters as early as 2026-2027, wrongly believing the deadline is single and further away | See the topic sheet |
Glossary of acronyms
| Acronym | Definition |
|---|---|
| BDN | Bunker Delivery Note |
| CII | Carbon Intensity Indicator |
| ECA | Emission Control Area (SECA where it covers sulphur only) |
| ETS | Emissions Trading System, the EU allowance trading scheme |
| FAME | Fatty Acid Methyl Esters, the biodiesel component of blends |
| FONAR | Fuel Oil Non-Availability Report |
| HFO | Heavy Fuel Oil |
| IAPP | International Air Pollution Prevention Certificate |
| IGF Code | International Code of Safety for Ships using Gases or other Low-flashpoint Fuels |
| ISO 8217 | International standard specification for marine fuels, seventh edition 2024 |
| LOP | Letter of Protest |
| MDO | Marine Diesel Oil |
| MFM | Mass Flow Meter |
| MGO | Marine Gas Oil |
| RFNBO | Renewable Fuels of Non-Biological Origin |
| ULSFO | Ultra Low Sulphur Fuel Oil |
| VCF | Volume Correction Factor, to standard volume at 15 °C |
| VLSFO | Very Low Sulphur Fuel Oil |
References and sources
Consolidated list of the sources cited. Updated as of August 2026.
| Category | Instrument, status and use |
|---|---|
| Primary statutory sources | MARPOL Annex VI regs 14 and 18; MEPC.320(74), MEPC.324(75), MEPC.362(79), MEPC.385(81), MEPC.392(82), MEPC.407(84). Status and operational dates checked separately. |
| Fuel quality and measurement | ISO 8217:2024 (7th edition), as contractually incorporated; applicable port MFM standard, including SS 648:2024 for Singapore. |
| EU carbon instruments | Regulation (EU) 2023/1805 (FuelEU Maritime); current EU ETS and MRV instruments. Their scopes and metrics are not identical. |
| Contract guidance | BIMCO FuelEU Maritime Clause 2024, CII Operations Clause 2022 and relevant ETS clauses: examples only, not automatically applicable law. |
| Sources to monitor | IMO Net-Zero Framework and future mandatory alternative-fuel provisions: not adopted or not yet mandatory as labelled; verify current status before use. |
This course is educational material for training purposes and does not constitute a professional certification or qualifying credential. Read the full disclaimer.