Covers details prior to, during and after all operations relating to and involving the safe arc welding on ferritic and austenitic steel land or offshore pipelines and process plant pipework which contain or have contained a process fluid and which are at least 5 mm thick.Cross References:BS 499:Part 1BS 638BS 679BS 2633 BS 3923:Part 1BS 4105BS 4515BS 4677 BS 5289BS 5996BS 6072BS 6443BS 8010:Part 1CP 2010:Part 2BS EN 167BS EN 168BS EN 169BS EN 287-1BS EN 288-3BS EN 439BS EN 30012-1BS EN 50078BS EN 60974-11BS EN 60974-12BS EN ISO 9000