The latest version of the internationally recognised standard for marine fuel specification, ISO 8217, has been released by the International Organization for Standardization (ISO). This seventh edition, ISO 8217:2024, is one of the most significant revisions to date, featuring substantial updates to grades and parameters, new terminology for bio products, and the addition of two tables to categorise residual marine fuels. These tables distinguish between fuels with sulphur content up to 0.5% (predominantly VLSFO) and those above 0.5%, as well as a table for bio-residual marine fuels.
UPDATES AND ADDITIONS TO CLAUSES
Clause 5.1: Updated to be more inclusive in terms of the fuel composition (renewables & synthetics)
Clause 5.2: Updated to reference added substances and chemical species
Clause 5.3: Referenced inorganic acids & organic chlorides, and fuels shall be free of these compounds
Clause 6-10: Define test methods, interpretation of results, and other general requirements (new)
Bunker suppliers must ensure fuel deliveries are free from organic chlorides and other harmful substances according to the latest standard.
LIST OF TABLES IN ISO 8217:2024
Table 1 – Distillates and bio-distillate marine fuels (DM/DF grades)
- Up to 100% FAME for DF grades
- Reporting of FAME content & Net Heat of Combustion for DF grades
- Minimum Cetane Number & Oxidation Stability requirements for DF grades
- Removal of winter/summer quality variation for Cloud Point & Cold Filter Plugging Point
Table 2 – Residual fuels with sulphur content up to 0.50% by mass (RM low sulphur grades) – New
- New grades – 0.10% & 0.50% sulphur
- De minimis level of FAME
- Expanded stability parameter requirement and reporting
- Removal of winter/summer quality variation for Pour Point
- Minimum Kinematic Viscosity requirements
Table 3 – Bio-residual marine fuels (RF grades) – New
- New grades – Up to 100% FAME
- Reporting of FAME content & Net Heat of Combustion
- Expanded stability parameter requirement and reporting
- Removal of winter/summer quality variation for Pour Point
- Minimum Kinematic Viscosity requirements
Table 4 – Residual fuels with sulfur content above 0.50% by mass (RM high sulphur grades)
- Reduced number of grades
- De minimis level of FAME
- Two options for stability parameter accepted for reporting
- Removal of winter/summer quality variation for Pour Point
- Minimum Kinematic Viscosity requirements
In addition, all tables now include a general requirement to comply with clauses 5-10, ensuring comprehensive adherence to the latest fuel standard.
UPDATED ANNEXES (ANNEX A to K)
Annex A: Bio-based liquid fuels including FAME – Expanded
Annex B: Composition of marine fuels – Expanded
Annex C: Ignition characteristics of residual marine fuels
Annex D: Hydrogen sulfide
Annex E: Acid Number
Annex F: Cold flow characteristics – New
Annex G: Ash – formerly Annex F
Annex H: Stability of residual fuels – New
Annex I: Unrefined used lubricating oil – formerly Annex G
Annex J: Specific energy – formerly Annex H
Annex K: Characterization of residual marine fuels – New
In practical terms, the latest ISO 8217:2024 update provides clearer parameters and specific requirements. It stipulates that all tables must adhere to “General Requirements – Clauses 5 to 10,” which reduces ambiguity and limits subjective interpretation when delivering to this standard.
To maintain best practices, it is crucial to ensure that charterparties and bunker contracts clearly specify the required version of fuel standards, the fuel grade, and any modifications to the reference standards for the fuel being supplied. This helps mitigate the risk of bunker disputes.
Shipowners are advised to understand these changes and review their operational and contractual practices to align with and stay updated on the latest fuel standards.