Standards are recognized rules of technology which may be applied to the practical implementation of general requirements (i.e. the Essential Safety Requirements (ESRs) of the Machinery Safety Regulation (Maschinen-Sicherheits-verordnung, MSV 2010). In principle, standards are not binding, but the legislator may declare them as binding (i.e. under the Electrical Engineering ACT (Elektrotechnikrecht). For products bearing CE marking, a binding declaration is not possible under EU legislation, even though their use is recommended. A distinction is made between national standards (in Austria, “ÖNORM” of the ON), European (harmonised) standards (“EN” of CEN) and global standards (ISO standards).