A principal contractor has been convicted and fined $300,000 after failing to respond to warning signs that a subcontractor's operations were unsafe, leading to a worker receiving an electric shock.

In December 2022, the worker sustained the electric shock when a 16-metre steel reinforcement cage buckled and made contact with two 11,000-volt overhead powerlines at a North Wollongong construction site.

The worker and a colleague were assisting a mobile plant operator to lift and position the cage into a previously bored hole when he heard a breaking noise and moved away, moments before the cage struck the lines.

Although the worker was not touching the cage, he was standing on wet, muddy ground and experienced a surge of electricity passing through his body. He was transported by ambulance to hospital, examined and discharged, and returned to work the following day.

Following a SafeWork NSW investigation, the PCBU was charged with and pleaded guilty to exposing the worker to a risk of serious injury or death, contrary to section 32 of the State Work Health and Safety Act 2011.

In Industrial Court proceedings, the PCBU acknowledged it could have redirected the overhead powerlines underground, implemented separation controls for mobile plant operating near live overhead powerlines, and properly reviewed the subcontractor's safe work method statement to minimise site risks.

SafeWork submitted the offence was within the high range of objective seriousness, arguing the avoidance of death or serious injury was "serendipitous" rather than the result of the PCBU's safety planning. The method for moving steel reinforcement cages at the site was "an incident waiting to happen", it added.

NSW Industrial Court Justice Jane Paingakulam noted it was agreed that the subcontractor's SWMS was signed by workers after the incident and was backdated, suggesting the PCBU failed to review it at the relevant time.

She also noted a significant contributing factor was the workers' lack of necessary qualifications, training and experience to perform the work safely. While it was the subcontractor's responsibility to engage qualified workers, the PCBU approved the site induction of workers who both explicitly stated they did not possess trade licences or high-risk certificates.

"That should have prompted some investigation by [the PCBU] into the appropriateness of the workforce and the systems that [the subcontractor] had in place," Justice Paingakulam emphasised.

The PCBU also failed to address the absence of the subcontractor's risk assessment for the piling rig, despite its own WHS management plan requiring one for mobile plant.

Taking these matters into account, Justice Paingakulam found the offence fell above the mid-range of objective seriousness, assessing the PCBU's culpability based on its failure to act on warning signs that the subcontractor's operations were unsafe.

She determined an appropriate penalty was $400,000, reduced by 25 per cent to reflect the guilty plea, imposing a fine of $300,000.

Key lessons for PCBUs:

• Properly review subcontractor safe work method statements before work commences
• Act on warning signs that subcontractors may be operating unsafely
• Verify subcontractor workers have appropriate qualifications and training
• Implement separation controls for mobile plant near overhead powerlines
• Ensure subcontractors conduct required risk assessments for mobile plant