EN590DieselSpecificationsExplained

EN590 is one of the most widely referenced specifications in the global fuel trade, and also one of the most frequently misunderstood — buyers often treat it as a single fixed formula, when it is actually a European standard with several parameters, tolerances, and regional variants built in. Understanding what each figure on a Certificate of Analysis actually represents makes it much easier to evaluate whether a cargo genuinely meets the specification a buyer needs.

What EN590 Is

EN590 is a European standard, maintained by the European Committee for Standardization (CEN), that specifies the requirements for automotive diesel fuel — the road-grade gasoil used in diesel-engine vehicles across Europe and widely adopted or referenced in fuel specifications well beyond Europe. The current version in general use is EN 590:2013+A1:2017, reflecting periodic amendments as vehicle emissions technology and fuel quality requirements evolve. It sits alongside equivalent standards used elsewhere — ASTM D975 in the United States, for example — that cover broadly similar ground with different specific limits and test methods.

The Parameters That Matter Most

Sulphur content. The single most consequential figure on an EN590 Certificate of Analysis. The current standard caps sulphur at 10 mg/kg (10 PPM), a level low enough to qualify as Ultra-Low Sulphur Diesel. This matters for two reasons: sulphur oxides are a major air pollutant in their own right, and sulphur compounds damage the catalytic converters and particulate filters used to meet modern Euro 5 and Euro 6 vehicle emissions standards. The move from older, higher-sulphur diesel to the current 10 PPM limit was driven directly by the emissions-control hardware fitted to virtually every modern diesel engine.

Cetane number. A measure of ignition quality — how readily the fuel ignites under compression, analogous to octane rating for petrol engines, though the two measure opposite properties. EN590 sets a minimum cetane number of 51. A higher cetane number means shorter ignition delay, smoother combustion, and easier cold starting; fuel below the minimum can cause rough running and harder starts, particularly in cold weather.

Density at 15°C. Specified within a band, typically 820–845 kg/m³. Density affects both combustion characteristics and the energy content per litre, and it is one of the parameters checked most routinely because it can be measured quickly and reliably in the field, giving an early indication of whether a cargo is likely to meet its full specification before laboratory results for other parameters come back.

Flash point. The minimum temperature at which the fuel's vapour will ignite in the presence of an ignition source — set at a minimum of 55°C under EN590. This is fundamentally a safety and handling specification, governing how the fuel can be stored, transported, and handled without excessive fire risk, rather than a performance characteristic.

Viscosity. Specified within a range (roughly 2.00–4.50 mm²/s at 40°C under EN590), viscosity affects fuel injector performance and lubrication of the fuel system. Fuel outside the specified range can cause poor atomisation in the injector or inadequate lubrication of moving parts within the fuel pump.

Cold Filter Plugging Point (CFPP). The lowest temperature at which the fuel will still flow through a standard filter without wax crystallisation blocking it. Because EN590 is used across a wide range of climates, CFPP is one of the few parameters that varies by grade and season — colder markets specify lower (more negative) CFPP grades, often described informally as "winter grade" or "Arctic grade" diesel.

FAME (biodiesel) content. EN590 permits blending with Fatty Acid Methyl Ester up to 7% by volume, with fuel at that ceiling commonly labelled B7. The exact FAME percentage in a given cargo can range anywhere from 0% up to 7%, so buyers whose equipment has known sensitivities to biodiesel content should always confirm the specific blend ratio rather than assuming a cargo sits at the maximum or contains none at all.

Why the Specification Keeps Tightening

Every major revision to EN590 over the past two decades has moved in the same direction: lower sulphur limits, tighter tolerances, and closer alignment with the emissions-control technology fitted to new vehicles. This is a regulatory response to vehicle emissions standards (the Euro 5 and Euro 6 frameworks in particular) rather than a change in the underlying combustion chemistry of diesel itself — modern engines are simply less tolerant of impurities than older ones were, which pushed refiners toward increasingly aggressive desulphurisation processes to keep pace.

Verifying Compliance

A specification on paper is only as good as the inspection behind it. Every EN590 cargo we supply is independently tested by SGS, Intertek, or Bureau Veritas at the load port against the full parameter set described above, with results issued as a Certificate of Quality that buyers can rely on for their own quality assurance and, where relevant, for letter-of-credit documentation. Buyers new to sourcing EN590 diesel are welcome to request a sample Certificate of Analysis before contracting, so they know exactly what to expect on the parameters that matter most for their specific use case — whether that's cetane number for engine performance, CFPP for a cold-climate market, or FAME content for equipment compatibility.

Frequently Asked Questions