This European Standard establishes a material designation system either by symbols or by numbers for cast iron. The designation system by symbols is applicable to: a) standardized cast iron materials (see 2.1); b) non-standardized cast iron materials (see 2.2). The designation system by numbers is only applicable to standardized cast iron materials (see 2.1). NOTE The use of a designation system by symbols does not necessarily imply that the material is standardized.