Fuel Quality Specifications
A specification tells you what a fuel must be. This guide maps the standards that govern marine fuel, diesel, jet and biodiesel, the tests behind them and how they appear on a certificate of quality.
Every fuel cargo is bought against a specification: a standard that lists properties, limits and test methods. The standard may be international (ISO), European (EN), American (ASTM), or a company or pipeline specification built on one of them. The seller warrants that the product meets it, and the certificate of quality shows the test results that support that warranty.
Specifications are revised over time, so the edition matters. A contract that says "ISO 8217" without a year leaves room to argue about which limits apply. Our terminal team works to the specification and edition named in each storage agreement, and plans segregation, sampling and handling around it from the first receipt to the last delivery.
Which standard governs which fuel
The table maps the specifications most often named in contracts for the products we store and move. Several products have parallel US and European standards with similar but not identical limits, so a cargo can meet one and fail the other. Always test against the document the contract names.
| Product | Specification | Notes |
|---|---|---|
| Marine fuels, distillate and residual | ISO 8217:2024 | Grades such as DMA, DMZ and RMG 380; sulfur is set by MARPOL, not by the standard |
| Diesel fuel, US | ASTM D975 | Grades include No. 1-D and No. 2-D in S15, S500 and S5000 sulfur classes; up to 5% biodiesel |
| Automotive diesel, Europe | EN 590 | Sulfur max 10 mg/kg, FAME up to 7% v/v, cetane number min 51 |
| Jet fuel (Jet A, Jet A-1) | ASTM D1655; DEF STAN 91-091 | Freeze point max -40°C for Jet A and -47°C for Jet A-1 |
| Synthetic jet blends (SAF) | ASTM D7566 | Blends certified to D7566 are treated as meeting D1655 |
| Biodiesel (FAME) blendstock | ASTM D6751; EN 14214 | B100 for blending; EN 14214 requires ester content of at least 96.5% m/m |
| Paraffinic diesel (HVO, GTL) | EN 15940 | Renewable diesel with low density and high cetane |
| Gasoline | ASTM D4814; EN 228 | Volatility classes vary by season and region |
ISO 8217:2024 in brief
ISO 8217 sets requirements for marine fuels as delivered to the ship. Distillate grades start with DM (DMX, DMA, DMZ, DMB) and residual grades with RM. In a residual grade the number is the maximum kinematic viscosity at 50°C in mm²/s, so RMG 380 is limited to 380 cSt at 50°C. The 2024 edition is current and adds requirements for bio-blended fuels.
Sulfur limits do not come from ISO 8217. They come from MARPOL Annex VI: 0.50% m/m worldwide since 1 January 2020 and 0.10% m/m inside Emission Control Areas. Ships fitted with approved exhaust gas cleaning systems may burn higher-sulfur fuel. ISO 8217 also requires fuel to be free of material that makes it unacceptable for use, such as added inorganic acids or chemical waste.
Diesel and biodiesel, US and European rules
In the US, ASTM D975 covers diesel fuel, with S15, ultra-low sulfur diesel at 15 ppm maximum, the grade for on-road use. Blends from B6 to B20 fall under ASTM D7467, and the B100 blendstock must meet ASTM D6751. In Europe, EN 590 diesel may contain up to 7% FAME, and that FAME must itself meet EN 14214.
Renewable diesel, or hydrotreated vegetable oil (HVO), is a paraffinic hydrocarbon, not an ester. It can meet ASTM D975 in the US and is specified under EN 15940 in Europe. It stores and handles much like conventional diesel, whereas FAME needs closer attention to water, oxidation stability and cold-flow behavior in tank.
Jet fuel and SAF
Jet fuel is the most tightly controlled product a terminal handles. Jet A-1 is certified to ASTM D1655 or DEF STAN 91-091, and documentary traceability must hold from refinery to aircraft. Sustainable aviation fuel components are produced under ASTM D7566, blended with conventional jet, certified, and from then on handled as standard Jet A or Jet A-1.
- Dedicated tanks, lines and filtration, kept apart from other products
- Recertification testing after receipt into terminal storage, before release
- Water and particulate checks at receipt and delivery
- An unbroken chain of quality documents for every batch
Reading a certificate of quality
A certificate of quality lists each property, the test method, the specification limit and the result. Check that the methods match those the specification names, that the sample came from the right tank or ship at the right time, and that the laboratory signed it. The tests below appear on most fuel certificates.
| Property | Common test method | Why it matters |
|---|---|---|
| Density at 15°C | ASTM D4052; ISO 12185 | Quantity conversion and combustion quality |
| Kinematic viscosity | ASTM D445; ISO 3104 | Pumping and fuel injection |
| Flash point | ASTM D93; ISO 2719 | Safe storage and handling |
| Sulfur | ASTM D5453; ISO 8754 | Emissions compliance |
| Distillation | ASTM D86; ISO 3405 | Volatility and composition |
| Water and sediment | ASTM D2709 for middle distillates | Contamination and filter blocking |
| Cold properties | Cloud point, pour point, CFPP | Operability in cold weather |
Frequently asked questions
Can a diesel meet ASTM D975 but fail EN 590?
Yes. The standards overlap but differ. A US S15 diesel meets a 15 ppm sulfur limit, while EN 590 requires 10 mg/kg and also sets a density window of 820 to 845 kg/m³ at 15°C and a higher cetane minimum. Test against the specification the contract names.
What is the difference between FAME and HVO?
FAME is a fatty acid methyl ester made by transesterifying vegetable oils, used cooking oil or animal fats, and is specified under EN 14214 or ASTM D6751. HVO is made by hydrotreating similar feedstocks into paraffinic hydrocarbons and behaves much like fossil diesel.
Which edition of a specification applies?
The one the contract names. If no edition is named, the parties may argue for the edition current at the contract date or at delivery. Naming it, as in ISO 8217:2024, removes the argument before it starts.
Is product tested while it is in storage?
Product is sampled as the storage agreement and the specification require, typically at receipt and before delivery, and appointed independent inspectors test on behalf of buyers and sellers. The agreement should state which laboratory result governs if two results differ.
Related
Quality & Measurement Standards
API MPMS, API 650/653/2350, ASTM test methods, ISO 8217:2024 and independent inspection.
Read more
Refined Products Storage
Gasoline blendstocks, ULSD and jet fuel on segregated systems, with dye and additive injection.
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Renewables & Biofuels Storage
Ethanol, FAME, renewable diesel and SAF stored dry and warm, with records for ISCC and RINs.
Read more
Aviation Fuel Storage and Freight
Jet A and Jet A-1 handled with dedicated tankage, batch recertification and strict water control.
Read moreStoring a product with a tight specification?
Tell us the grade and the specification edition. We will propose segregation, sampling and handling to protect it.