SA: regulator issues safety warning over powerline contact risks

The following article is a news item provided for the benefit of the Workplace Health and Safety profession. Its content does not necessarily reflect the views of the Australian Institute of Health & Safety.
Tuesday, 8 November, 2022 - 12:15
Policy & legislation
South Australia

SafeWork SA recently warned builders and contractors in the residential construction sector to maintain safe clearance distances when working near overhead powerlines after multiple electric shocks and near misses that could have resulted in serious injuries or even death by electrocution.

SafeWork SA has received numerous notifications in recent months including electric shocks to two apprentices in October.

On 28 October, a first-year apprentice was carrying a purlin along the working deck of a scaffold and made contact with the powerline causing an electric shock.

Initial enquiries indicate the modular scaffold breached the safe clearance distance to an 11kV powerline by approximately 1.6 metres at the time of the incident.

Earlier in the month, a second-year apprentice lifted a metal purlin above his head, touching a low-voltage powerline which resulted in an electric shock.

A further three incidents involved plant striking an overhead powerline. While no serious injuries were sustained in any of the recent incidents, they all had the potential to cause major trauma or death.

SafeWork SA and the Office of the Technical Regulator (OTR) reminded builders and contractors in the residential construction sector to ensure workers and plant do not encroach on safe clearance distances.

Working near overhead powerlines can be fatal, according to SafeWork SA, which said touching them or straying into safe clearance distances can result in a serious electric shock, and simply being close to the line conductors may allow a ‘flashover’ or arc to take place. The risk of flashover increases as the line voltage increases.

Before carrying out work, a worksite inspection should be conducted to identify potential hazards including the presence of energised overhead powerlines or associated electrical equipment that may pose a risk.

The most effective way to eliminate any risk of electric shock is by turning off the power. The PCBU, principal contractor or the operating plant owner should discuss options for de-energising or re-routing the electricity supply with South Australian Power Networks (SAPN). De-energising or re-routing powerlines should be arranged with SAPN as quickly as possible as this can take some time to arrange. This includes complying with any SAPN requirements under relevant electrical safety legislation.

If eliminating the risk is not reasonably practicable, you must consider using substitution, isolation or engineering controls, or a combination of these control measures, to minimise the risk. This may include:

  • Substituting or replacing a hazard or hazardous work practice with a safer one. This may include performing the work another way, for example using non-conductive tools designed to reduce the possibility of direct contact with overhead powerlines.
  • Separating the hazard or hazardous work practice from people by erecting a physical barrier consisting of non-conductive material to prevent any part of plant or equipment or to prevent a person, anything held by a person, or anything attached to a person, from entering an unsafe distance.
  • Engineering controls are physical control measures to minimise risk, for example:
    • limiting movement of plant with mechanical stops
    • fitting plant with programmable zone-limiting devices
    • mechanically limiting slew speed of a crane to slow
    • using electrically insulated plant and equipment.
  • Administrative controls should only be considered when other higher-order control measures are not reasonably practicable, for example:
  • Identify overhead powerlines using The SARIG map or LocationSAMapViewer and/or talking to the property owner and/or OTR.
  • Conduct a site-specific risk assessment. Think about:
    • the type of plant and equipment/tools used
    • site and weather conditions – be aware that powerlines sag or sway in hot or windy weather
    • type of work being done
    • set-up and pack-up procedures.
  • Follow the safety advice given by SAPN and/or OTR.
  • Carefully plan tasks to be done near powerlines and work away from them whenever possible, not underneath them.
  • Manage and supervise the work to ensure safe work practices and procedures are followed.
  • Ensure Safe Work Method Statements (SWMS) for high risk construction work are developed when required.
  • Have appropriately trained and qualified people who are authorised to carry out the work.
  • Keep your workers and contractors informed about electrical safety:
    • induct and train your workers and contractors in safe work procedures, emergency procedures and safe clearance distances
    • ensure operators know the height and reach of machinery or hand-held items to be used
    • operators should use a spotter/safety observer when carrying out work near powerlines.
  • Make hazards more visible by:
    • using warning signs to indicate the location of overhead powerlines and defined work areas
    • arranging for SAPN to identify exposed energised low voltage conductors (up to and including 1000 volts) and fitting them with approved visual indicators like sheeting or sleeves such as tiger tails. A competent person should inspect visual indicators each day before starting plant operations
  • If visual indicators have moved or been damaged, SAPN should be contacted so they are replaced or located in the correct position.