Underground cable identification


18 April 2017

Across the ACT region there have been a number of recent incidents involving the cutting of energised underground power cables. In all cases before any underground power cable is cut – it must be identified and proven safe to touch by one of the following methods:

  • From each end and along the entire length of the cable; or
  • By approved Spiking and ID equipment (a spiking gun).

There is no other way to conclusively prove a cable as energised (or not) either visually or by other methods.

The ACT Work Safety Commissioner reminds all electrical workers involved in cutting power cables, to be advised that clear identification of the cable and approved testing to determine whether it is live is absolutely essential to keep all workers safe.

Pictured is an example of a Spiking gun in place before a cut. All workers are to remain clear of the cable during spiking operations as a large ‘Arc Flash’ can occur.

photo of exposed underground electrical cable hazard

Identification and testing

  • Always positively identify cables before cutting;
  • Plan all electrical works – an outage may be necessary;
  • A Safe Work Method Statement (SWMS) or Work Instruction must guide this high risk task;
  • Conduct a prestart risk assessment – always remove unnecessary persons or plant before Spiking;
  • Do not trust maps or other diagrams – use only as a guide and always positively identify the cable;
  • Remove personnel from the trench or pit before the Spiking gun is fired; and
  • If the cable can be identified at each end along the entire length and when it is proven de-energised and isolated – only then is hand cutting acceptable.

Further information

For further information contact WorkSafe ACT on 13 22 81 or email WorkSafe@act.gov.au.

This Alert contains information emerging during an investigation by WorkSafe ACT into the mentioned incident at the date of this report. The information contained in this report does not necessarily reflect the final outcome of WorkSafe’s views or proposed actions with respect to this incident. WorkSafe ACT does not warrant the information in this report is complete or up-to date and does not accept any liability to any person for the information in this report, or its use.

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