Key learnings from a High Potential incident.
HPI OSH Alert #480
Date of incident: 28 May 2016
Safety Flash issued: 08 June 2016
Just before the end of the work day an
operator of a 30 tonne excavator was
instructed to park the machine at the
front of the site.
Without using a spotter the operator
parked the machine next to the excavator attachments
as this was the most convenient location. The
excavator attachments had been placed underneath a
powerline. The barricading previously set up to
prevent access to the powerlines was moved during
the day and not replaced.
While trying to manoeuvre the excavator into place,
the vehicle made contact with the 440 volt overhead
powerline causing it to arc, break and fall to the
ground. The operator then exited the cab instead of
remaining in the vehicle until help arrived.
Why did this happen?
- Barricading preventing access to the powerline corridor was moved earlier in the day and was not
- The overhead powerlines were not considered in the contractor’s risk assessment as the original plan
was to exclude access to the powerline corridor.
- There was no Management of Change (MoC) process used or a review of the contractor’s risk
assessment when changes to site layout and laydown area occurred.
- The team that attended the Construction Risk Assessment Workshop and start-up meeting were not the
same team that undertook the demolition works.
- The subcontractors were a newly established company and there was no intense supervision by the
What will the business area involved in the incident do to stop this from happening again?
- Implement a Take 5 risk assessment tool to assess and manage changing circumstances. Provide
instruction to site workers through a toolbox meeting.
- Liaise with the supplier of mobile plant and attachments; communicate the issues arising from ongoing
problems with the couplings and attachments sourced from Perth and determine a resolution.
- Discuss the use of the Management of Change process (MoC) when the environment/job changes
- Reinforce that when tasks change there is a requirement to update the risk assessment.
- Reinforce the need for a spotter when excavators or cranes are working around powerlines
- Update the Phone Daily Review Meeting checklist to prompt questioning of organisation, work system,
documentation or engineering change.
- Reinforce the need for main contractors to formally nominate subcontractors in accordance with item six
on the Start-up Agenda Minutes, which states:
- Approvals required where subcontractors were not nominated in the Bid.
- Approvals required for subcontractors not on the approved list of Principal’s subcontractors (Refer to
list in Contract).
- Regional North West Projects team to carry out a toolbox topic at their next safety meeting which covers
the requirements for attendees at Start-Up meetings. This is to refer to the contract management
What will our organisation do to stop this from happening again?
- Update the minor works procedure (Cat D) to include contract management processes.
- Include the contract management process in the regional project leader induction package and share the learning with the regional Operational Engineering Forum.
What key learnings can you discuss with your team to stop this from happening
1. Safe Job Planning steps must be followed for all tasks completed onsite.
- Do you complete a new risk assessment before starting each new job/task during the day?
- Do contractors working under your supervision have a MoC process to ensure changes to site
conditions during the day are reviewed for OSH risks.
- Do you undertake a group risk assessment prior to commencing work onsite when there are multiple
work groups or people?
2. Risk workshops and Start-Up Meetings need to be undertaken with ALL of the key personnel
including site supervisors, Contractor Project Manager and Leading Hands.
- Do you complete a risk workshop or start-up meeting prior to work commencing involving a
- Do you know who is required to attend a Start-Up meeting or Risk Workshop?
- Have you discussed with your contractor the site laydown area locations and traffic movement plans?
3. After striking overhead powerlines with mobile plant, operators should not exit the machine
until advised to by the supply authority.
Are you aware of the safety requirements for operating machinery if you make contact with
Have you reviewed contractor/operator Verification of Competencies (VoCs) for operating plant and
If you would like further information about anything included in this HPI OSH Alert, please contact Charis
Neumann, Senior OSH Analyst Incidents on 6330 6629.