First published as AS A50—1946.Revised and redesignated AS 1172—1971.Second edition 1989.AS 1172—1989 revised and redesignated AS 1172.1—1993.Second edition 2005.Third edition 2014. First published as AS A50-1946. Revised and redesignated AS 1172-1971. Second edition 1989. AS 1172-1989 revised and redesignated AS 1172.1-1993. Second edition 2005. Third edition 2014. Reissued incorporating Amendment No. 1 (June 2018).