Originated in Australia, in part, as AS C66.1—1955, AS C154—1958, AS C90—1963, AS C173—1964, AS C175—1967, AS C183—1970 and AS/NZS 2053.6:1995.Originated in New Zealand, in part, as NZS 127:1949, NZS 2250.1:1969, NZS 6221.1:1972, NZS 6221.2:1972 and AS/NZS 2053.6:1995.Previous editions, in part, as AS/NZS 2053.2:2001, AS/NZS 2053.6:2001 and AS/NZS 2053.7:2002.Jointly revised, amalgamated and redesignated AS/NZS 61386.21:2015. Originated in Australia, in part, as AS C66.1-1955, AS C154-1958, AS C90-1963, AS C173-1964, AS C175-1967, AS C183-1970 and AS/NZS 2053.6:1995. Originated in New Zealand, in part, as NZS 127:1949, NZS 2250.1:1969, NZS 6221.1:1972, NZS 6221.2:1972 and AS/NZS 2053.6:1995. Previous editions, in part, as AS/NZS 2053.2:2001, AS/NZS 2053.6:2001 and AS/NZS 2053.7:2002. Jointly revised, amalgamated and redesignated AS/NZS 61386.21:2015. Reissued incorporating Amendment No. 1 (April 2020). Originated in Australia, in part, as AS C66.1-1955, AS C154-1958, AS C90-1963, AS C173-1964, AS C175-1967, AS C183-1970 and AS/NZS 2053.6:1995. Originated in New Zealand, in part, as NZS 127:1949, NZS 2250.1:1969, NZS 6221.1:1972, NZS 6221.2:1972 and AS/NZS 2053.6:1995. Previous editions, in part, as AS/NZS 2053.2:2001, AS/NZS 2053.6:2001 and AS/NZS 2053.7:2002. Jointly revised, amalgamated and redesignated AS/NZS 61386.21:2015. Reissued incorporating Amendment No. 1 (April 2020). Reissued incorporating Amendment No 2 (May 2023).