Felled tree contacts HV conductors

Background

Last year a forestry machine operator was removing trees during forest harvesting works. The machinery operator was using a feller buncher to hold and cut trees; a common tree felling technique with forest harvesting machines that enables the direction of a tree to be felled in a controlled manner if performed correctly. 

While felling a plantation tree adjacent to high voltage (HV) conductors the machinery operator slewed the feller buncher to the side, causing the felled tree to contact the HV conductors and resulting in an interruption to electricity supply.

This created an unsafe electrical situation that had the potential to cause fire, property damage, serious personal injury or in the worst circumstance an electrocution. Fortunately, no one was injured.

The incident was reported to the distribution business and to Energy Safe Victoria (ESV).

Investigation Findings

ESV conducted an investigation of this incident and found:

• worksite safety information related to the task being performed contained inconsistent and conflicting information regarding operational setbacks from electric lines when completing this type of work
• a failure to maintain the minimum distance between vegetation and protected aerial lines
• site safety precautions, such as warning flags or a registered spotter, were not used in line with the work site safety information that was provided.

ESV’s view is that the combination of these failures resulted in a breach of Electricity Safety legislation; heavy penalties may be applied to such breaches.

Key Lessons

• Ensure all site hazards are identified and actions to control the hazards are implemented.
• Ensure work procedures and practices place importance on the awareness of the location of electric lines on and near the worksite and that effective hazard controls are implemented.
• Use No Go Zone principles when undertaking forest harvesting works in the vicinity of live electrical apparatus.
• Regularly reassess each worksite for hazards when completing work near electric lines.

Important information

• Failing to identify hazards at the work site will place workers at risk of serious personal injury or in the worst circumstance, electrocution.
• Ensure each individual work site is assessed for hazards and controls are implemented to manage risks.
• Look up and Live – identify all locations where powerlines are within or adjacent to the worksite prior to starting works.
• Worksites that are near electric lines are dangerous. Vegetation management workers have been seriously injured and electrocuted when the have made contact with both uninsulated low voltage and high voltage electric lines. 

Enforcement outcomes

Having completed its investigation of this incident it is ESV’s view the machinery operator failed to ensure the tree he was felling maintained the required clearance from the electric line, which is require by the Electricity Safety (General) Regulations 2019 (the Regulations). Failing to maintain the minimum clearance is a breach of the Regulations.  
ESV may choose to prosecute or take other enforcement action where it considers a breach of the Electricity Safety Act 1998 or Electricity Safety Regulations has occurred.