This bulletin explains the terminology of metallic coated steel sheet and strip used in Australian standards. Steel sheet materials typically used in building are covered by AS 1397 for metallic coated steel or AS 2728 for prepainted steel. Products manufactured from these steels are typically covered by AS 2179 and AS 2180 for rainwater goods, AS 1445 for corrugated steel sheet and AS 1562 for design and installation of metal roofing. These standards adopt common terminology for coating class and mechanical properties. Product specifications should state the base steel thickness in mm, the strength grade and the coating class.