The aim of any earthing system is to ensure that there is a path from the source of any electrical charge to earth of less than 10 Ohms. Typically this is achieved by producing an all metal route for the charge to follow. The means to achieve this varies from organisation to organisation, but typically if the pipework is all constructed of fixed flange items, it is acceptable to bolt these together using stud bolts and star washers. The star washers will bite through any paintwork on the flanges and will bite into the nuts on the studs. This provides an earth path from flange to flange. However, if rotating flanges are used, either using welded on stub ends or Conrac/Vanstone style ends, the star washer approach breaks down since it cannot guarantee earth continuity from flange to stub end. Traditionally, this problem has been tackled by welding on earthing lugs or studs onto each individual metal item. These studs of lugs are then all linked using copper earth straps. While effective, this approach is both time consuming and expensive.