European Union Directive 2009/30/EC sets important health and environment based technical specifications for fuels to be used with positive ignition and compression-ignition engines, as well as a target for the reduction of life cycle greenhouse gas emissions. For compression ignition engine fuels, the technical specification regulated by this directive include: cetane number, sulfur content, polycyclic aromatic hydrocarbons, density and some distillation characteristics.
These specifications as well as additional fuel quality requirements are stated in standards developed by the European Standards Organization (CEN). The first set of standards for automotive fuels, ratified by CEN on 16 March 1993, had been adopted by all Member States by September 1993. Three standards cover automotive fuels quality: the EN 590 for diesel fuel, the EN 228 for gasoline, and EN 589 for automotive LPG. The standards are periodically updated to reflect changes in specifications, such as the mandatory reductions in sulfur content.
To provide options for different climates, the EN 590 standard specifies six Temperature Climate Grades of diesel fuel (Grade A...F) which differ in the CFPP value. In addition, there are five Arctic Classes of diesel fuel (Class 0...4) characterized by different properties. Each country shall detail requirements for a summer and winter grade, and may also include intermediate or regional grades as justified by national climate conditions.
Mandatory environmental fuel specifications are introduced by EU Directives. The following are the most important steps in the evolution of EU diesel fuel specifications:
- Effective 1994.10, a maximum sulfur limit of 0.2% (wt.) was introduced for all gas oils, including diesel fuel. The minimum cetane number was 49.
- 1996.10: A maximum sulfur limit of 0.05% (wt.) = 500 ppm for diesel fuel.
- 2000.01: A maximum sulfur limit of 350 ppm and cetane number of 51 for diesel fuel.
- 2005.01: A maximum sulfur limit of 50 ppm for diesel fuel for highway vehicles. “Sulfur-free” 10 ppm sulfur diesel fuel must be available.
- 2009.01: A maximum sulfur limit of 10 ppm (“sulfur-free”) for diesel fuel for highway vehicles.
Sulfur content in fuels for mobile nonroad vehicles—including mobile machinery, agricultural and forestry tractors, as well as inland waterway vessels and recreational craft—is limited at 1000 ppm from 2008, and at 10 mg/kg from 2011 (certain flexibilities apply).
In addition to sulfur, environmental specifications apply to other fuel properties, including maximum aromatics content and FAME biodiesel content.