To ensure safety, any electrical installation in a residential unit, shop and office and the communal electrical installation of any building must be inspected, tested and certified on a Periodic Test Certificate (EMSD Form WR2) at least once every 5 years if the approved loading exceeds 100A (Amperes).

The approved loading of the communal electrical installation in most buildings exceeds 100A, whereas that of the electrical installation in general residential units usually does not exceed. If in doubt, the owners may arrange a registered electrical contractor to check.

After inspection, testing and repair, the registered electrical contractor and worker shall issue a Periodic Test Certificate to confirm that the electrical installation is safe and complies with the statutory safety requirements.

The owners of the electrical installation shall submit the certificate to EMSD for endorsement. After that, they should properly retain the certificate for future inspection by EMSD.

Owners may consult a registered electrical contractor / worker for the checklists for periodic inspection and testing for electrical installations.