First published as AS/NZS 60079.1.1:2002, AS/NZS 60079.4:2000, AS/NZS 60079.12:2000 and AS/NZS 60079.20:2000.Revised, amalgamated and redesignated AS/NZS 60079.20.1:2012. Originated in part as AS/NZS 60079.1.1:2002, AS/NZS 60079.4:2000, AS/NZS 60079.12:2000 and AS/NZS 60079.20:2000. Revised, amalgamated and redesignated AS/NZS 60079.20.1:2012.