BS EN 1591-4:2013 Flanges and their joints. Qualification of personnel competency in the assembly of the bolted connections of critical service pressurized systems
2013BS EN 1591-4:2013 Flanges and their joints. Qualification of personnel competency in the assembly of the bolted connections of critical service pressurized systems
2007BS DD CEN/TS 1591-4:2007 Flanges and their joints - Design rules for gasketed circular flange connections - Qualification of personnel competency in the assembly of bolted joints fitted to equipment subject to the Pressure Equipment Directive