The quality of automotive fuels in the European Union is specified by 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. The quality of European diesel fuels is specified by the EN 590 standard. While these specifications are not mandatory, they are observed by all fuel suppliers in Europe. Beginning from the late 1990s, several diesel fuel properties—including cetane number, sulfur content and FAME biodiesel content—are also subject to environmental regulations. EN590 describes the physical properties that all automotive diesel fuel must meet if it is to be sold in the European Union, Croatia, Iceland, Norway and Switzerland. Based on 98/70/EG it allows the blending of up to 7% fatty acid methyl ester biodiesel with 'conventional' diesel - a 7:93 mix.