NT: safety alert issued over overhead electrical infrastructure

The following article is a news item provided for the benefit of members. Its content does not necessarily reflect the views of the Australian Institute of Health & Safety.
Date: 
Wednesday, 2 December, 2020 - 10:45
Category: 
Policy & legislation
Location: 
Northern Territory

NT WorkSafe recently issued a safety alert about potential electrical safety risks posed by damaged, defective or degraded overhead electrical infrastructure.

The alert was issued following a recent incident in which a person in a remote community was fatally injured after attempting to climb into a secured external area of a residence.

The preliminary investigation findings suggest that the person suffered an electric shock which, combined with other circumstances, contributed to the death.

An examination of the property’s electrical installation and overhead power lines found damaged insulation on the overhead power line and a connection that had the potential to energise the entire roof, posing a risk of electric shock or electrocution to any person who made contact with it, directly or indirectly.

The alert said there were a number of contributing factors:

  • The overhead power line was subject to various environmental factors that caused the insulation to become damaged
  • The damaged area of insulation made contact with a stainless steel braided wire, causing the wire to become energised
  • The stainless-steel braided wire was connected to a metallic gooseneck riser hook, attached to the metal roof, which became energised at 240 volts
  • Instrument checks found that neither the roof structure nor the gooseneck were solidly earthed as required under AS/NZS 3000 Wiring Rules.
  • Defects were found on the low voltage service clamp installation and service conductor.

The alert subsequently recommended a number of actions and said that any member of the public can report a fault or damage to Power and Water Corporation property or infrastructure by submitting an online fault report on the Power and Water website.

Homeowners and occupiers of residences connected by overhead power lines should regularly look up to see if there are any obvious visual signs of damage or degradation.

If you notice deterioration or damage, contact a qualified electrical contractor or Power and Water to assess the risk.

Qualified electrical workers and contractors were reminded to:

  • Conduct a risk assessment before commencing electrical work
  • Inspect all points of connection to power network infrastructure and ensure they are compliant
  • Ensure all structural metalwork is solidly earthed as required under AS/NZS 3000 Wiring Rules