Workers were installing cable tray covers at a water recycling plant using a boom lift. While securing the final inclined cover in place with screws, one of the screws went through a live 240V cable, damaging the insulation. This caused a minor arc but no one was injured as they were standing on rubber matting. The live cable was then de-energized and further work was suspended pending an investigation. Key lessons included slowing down when tasks deviate from normal plans, reviewing site-specific risks in safe work method statements, and conducting audits to identify any electrical circuits still lacking residual current device protection.

1. Cable tray installation electrocution
near miss
3 July 2019
What happened and why?
Workers were installing new cable tray covers at
Penrith Water Recycling Plant using a boom-lift
man-box. The final cover was an inclined cover
which made it difficult to install the clamps used on
other covers and the method of fixing was changed
to screws.
While securing the cover in place, the screw went
through a 240V live cable. The insulation of the
cable was damaged and the screw touched the
copper conductor causing a minor arc. Workers
were standing on rubber matting and were not
injured.
What did Sydney Water do?
• Work was immediately stopped and
the area sectioned off
• The live 240V cable was de-
energized
• Further cable tray project work
suspended until investigation of the
incident complete
Key Lessons
• ‘Slow down to Speed up’ - 90%
of the work was completed without
the need for screws and only
utilising clamps. As this section
was inclined, the normal clamps
were not suitable to hold the cover
in place, therefore the work party
decided to install screws.
Since the job plan had deviated
from its normal course, there was
a need to stop, reassess and look
for a safer way to complete the
task. In the incident debrief, a
much safer option of steel
strapping was identified very
quickly eliminating the risk
altogether.
• Review generic safe work method
statements (SWMS) for every job
and include situation/job specific
risks. Any change should be risk
assessed and updated in SWMS.
• There are still electrical circuits
without RCD protection. All sites
should carry out an auditIncident lesson no. INC 26338
Issue Date: 10 July 2019
Approved by: Insert Name of person who approved this communication
Penrith WRP Electrical Incident