4.5.1 Piping systems for essential services should
be subjected to a test pressure not less than 1.5 times the design
pressure of the system.
4.5.2 Piping systems for non-essential services
should be checked for leakage under operational conditions.
4.5.3 For piping required to be electrically conductive,
the resistance to earth should be checked. Earthing wires should be
accessible for inspection.