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Details of successful prosecution against E218809

Incident description

The defendant held duties under s. 19(1) of the Work Health and Safety Act 2011 being a sole trader conducting the business of construction work.

On 8 August 2016, a worker was seriously injured when the trench he was working in collapsed.

He was working in a trench that was over 4 metres deep. The defendant supplied a trench box that was only 2.4 metres deep and rested on what he thought was solid ground for the bottom 1.5 metres. That solid wall collapsed and the worker sustained serious injuries including a fractured pelvis and urethral damage.

The defendant owned and operated an excavator, being a CAT 329D 30 tonne excavator. He had also hired a smaller excavator. Both were used in excavating the trench to lay sewer pipes. After excavating the trench box was placed into the trench by the defendant using the 30 tonne excavator. The injured worker worked from inside the trench box. Two PVC pipes were laid in the trench before the box would be moved to lay further pipes. The worker smoothed and levelled the bottom of the trench and then an excavator poured bedding sand into it.

A labourer worked with the injured worker by standing on the ground next to the trench and relaying hand signals to excavator operators. He also handed the sewer pipes to the injured worker, who then laid and joined them and then covered the pipes with sand. The trench box sat level with the ground and did not cover the lower 1.5 metres of trench wall.

Court result

The defendant pleaded guilty in the Southport Magistrates Court on 12 December 2016 to breaching s. 32 of the Work Health and Safety Act 2011, having failed to meet his work health and safety duties and was sentenced.

Magistrate Robert Walker fined the defendant $30,000 and ordered professional and court costs totaling $1089.40. No conviction was recorded.

In reaching a decision, the Magistrate considered the defendant had a serious lapse of judgment in conducting the work and assuming the rock wall not covered by the trench box was safe.

While he hired a trench box in an attempt to address safety issues those efforts were insufficient. The Court referred to the Excavation Code of Practice 2013 which included “Ground collapse is one of the primary risks to be controlled in excavation work' and concerning ground materials in that 'hard compact soils…can cause the most trouble because the face 'looks good' and this often leads to risks being taken.  Loose or running material is often the safest, because the need for safety precautions is obvious from the start.”

In giving the defendant the benefit of an order that no conviction be recorded,  the Magistrate acknowledged his cooperation with the investigation, timely plea of guilty, good safety record, no previous convictions under occupational health and safety legislation and post incident measures including always using a trench box to cover the whole of an excavation.

Considerations for prevention

(commentary under this heading is not part of the court's decision)

When working in the construction industry where there is exposure to risks from excavation and trench wall collapse, duty holders should apply a risk management approach to ensure the selection of suitable control measures.

Risk management involves identifying the hazards, evaluating the consequences and likelihood of harm that may result from the hazard, deciding and implementing control measures to prevent or minimise the level of the risk from the hazard and monitoring the effectiveness of the control measures to ensure they remain working correctly.

When deciding and implementing control measures associated with the risk of trench collapse, obligation holders should consider the practical advice set out in the Excavation Work Code of Practice 2021 (PDF, 1.9 MB).


Date of offence:
Multiple fractures of the pelvis and urethral damage
Southport Magistrates Court
Robert Walker
s.32 of the duty under s.19(1) of the Work Health and Safety Act 2011
Decision date:
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Conviction recorded:
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