This European Standard specifies requirements for the design, materials, manufacturing and testing of pressure vessels and pressure vessel parts intended for use with a maximum allowable pressure, PS, equal or less 50 bar and shell wall thicknesses not exceeding 60 mm, that are constructed of spheroidal graphite cast iron. NOTE The grades of spheroidal graphite cast iron allowed are listed in Tables 5.1-1 and 5.1-2. Service conditions are given in clause 4.