This European Standard lays down harmonized identifiers for marketed liquid and gaseous fuels. The requirements in this standard are set to complement information needs of users regarding the fuel- and vehicle-compatibility that are placed on the market. The development of this standard focused on vehicles placed on the market for the first time, which does not preclude the application of this standard also to vehicles already in circulation. 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 non-stationary applications.