The frequency of inspection and testing varies for different work situations. For construction work the inspection and testing intervals are described in the Code of Practice: Electrical practices for construction work.
For all other workplaces the inspection and testing intervals are described in the Standard, AS/NZS 3760 but only need be applied to electrical equipment that has been assessed as operating in a hostile operating environment as described in clause 64 of the OHS Regulation.
For a quick-reference table to the intervals outlined in the standard, please see here.
extracted from "COMPETENT PERSON FOR TESTING AND TAGGING ELECTRICAL EQUIPMENT" WorkCover publication