Hong Kong Regulations

ELECTRICITY SUPPLY REGULATIONS - REGULATION 6

Testing of insulation of all parts of high pressure circuit

A high pressure circuit shall not be brought into use unless the insulation of
every part thereof has withstood the continuous application, during 1 hour, in
the case of every electric line, of a pressure equal to the full working
pressure to which it is intended to be subjected in use, and in the case of
every machine, device or apparatus, of a pressure equal to the full working
pressure to which it is intended to be subjected. The company shall duly
record the results of each test.