Electrical rule change to be reviewed

Electrical inspectors say a rule change has increased the risk of people being electrocuted in homes and businesses. 

The change lifted a ban on inserting a switch, circuit or fuse into mains power earthing systems. The rule change in November 2025 was introduced to support future technologies like electric vehicle charging and improve disaster resilience in mains systems.

Previously, inserting any switching device into the combined protective earth and neutral (PEN) conductor was strictly prohibited because interrupting the earthing path was considered a serious safety risk.

The Electrical Inspectors Association has written to the government asking WorkSafe to take action. Energy Minister Simon Watts said he took the industry’s feedback seriously.

“The regulatory amendment lays the foundation for future measures to ensure electric vehicle charging meets safety expectations, and allow for improved disaster resilience,” Watts said.

Inspectors from the New Zealand Electrical Inspectors Association argue the PEN conductor is critical to safety, and introducing any switching device into it can create ‘dangerous touch voltages’ even when a system is otherwise fault‑free. 

In practical terms, this could mean metal surfaces in homes or workplaces, such as appliance casings or switchboards, becoming energised without warning.

They say that if the neutral is opened while the live conductors remain connected, earthed metalwork can rise to mains voltage: a scenario they describe as ‘nearly impossible’ to escape without severe shock.

The industry’s concerns have since drawn support from Engineering New Zealand and the Master Electricians Association, which say the change was sudden, poorly consulted on, and creates confusion for installers and inspectors. 

They argue that New Zealand’s ageing building stock and varied installation standards may compound the risks if the switching of the PEN conductor is not tightly controlled.

They’ve also highlighted that other jurisdictions, such as Australia, retain protections against switching the PEN conductor and that similar safety standards abroad have not adopted this change.

WorkSafe has acknowledged the concerns and has committed to publishing interim guidance for electrical workers. Industry representatives say that waiting for a formal review is too slow, given the perceived risks.