This European Standard lays down harmonized identifiers for marketed liquid and gaseous fuels. The requirements in this standard are to complement the informational needs of users regarding the compatibility between the fuels and the vehicles that are placed on the market. The identifier is intended to be visualized at dispensers and refuelling points, on vehicles, in motor vehicle dealerships and in consumer manuals as described in this document. Marketed fuels include for example petroleum-derived fuels, synthetic fuels, biofuels, natural gas, liquefied petroleum gas, hydrogen and biogas and blends of the aforementioned delivered to mobile applications.