In May 2019, an operator of a forestry skidder at a rural property became entangled in the cable winch mechanism at the rear of the machine.
For reasons yet to be established, while “snigging” (dragging tree logs using ropes or chains) with the skidder, the operator's leg was trapped in the cable winch up to his hip. The operator could not free himself and required a traumatic surgical amputation on-site to be released from the machine.
Investigations are continuing.
Preventing a similar incident
Skidders are used in forest harvesting operations for “snigging” cut trees or logs. An attachment, such as a large grapple or winch cable, is attached to the rear of the skidder and used to pull cut trees or logs to a collection point. Skidders are also known as rubber-tyred tractors or crawler tractors. They are often used in areas that are difficult for other forestry machines to access.
To commence snigging with a winch, the operator parks the skidder near a tree or log. Then the operator or another worker walks the winch cable to the trees or logs and hooks them up. When the operator is back in the cabin of the skidder, they winch the logs or trees towards the rear of the skidder and then “snig” (move) them to the collection point.
Most skidders are equipped with a winch designed for direct pull operations only (pulling in line with the winch's centre line). Winching at an angle is hazardous because there is a risk of pulling the machine on its side and breaking or damaging the cable. Operators must always be aware and alert when using the winch as this fitted part is extremely powerful and can, at times, pull the skidder backwards.
Duties of a PCBU include ensuring:
- the provision and maintenance of safe plant; and
- the inspection and maintenance of the plant is carried out by a competent person in accordance with the manufacturer's instructions.
Higher order risk controls including a safe system of work should be implemented to manage the risks associated with inspection and maintenance of the plant. Plant includes anything fitted, connected or attached to the plant.
The PCBU must ensure that for any rubber tyred skidder and crawler tractor:
- the rubber tyres that are in good order, with sufficient tread pattern to provide traction
- the winch fitted to the skidder is suitable for the skidder's pulling capacity
- is regularly serviced and maintained, always keeping it in good working order, as specified in the operator's handbook.
In addition, a PCBU must also provide the worker with information, training and instruction that is suitable and adequate for:
- the nature of the work to be carried out by the worker
- the nature of the risks associated with the work (at the time the information, training or instruction is provided)
- the control measures implemented to deal with these risks.
When operating any machinery that uses winches:
- always read the instructions provided by the manufacturer and follow all safety directions
- never place yourself or others in a position where you could be entangled and pulled by the cable winch or the material being moved
- never place yourself or others in a position where you could be crushed or struck in the event of the winch failure
- ensure workers working on, near the winch are adequately trained and supervised.
Since 2013, there has been an average of 22 accepted workers' compensation claims each year for injuries relating to being trapped by mobile plant within the agricultural, forestry and fishing industries. Fifty per cent of these claims involve serious injuries with five or more days off work.
In the same period, we have been notified of 59 incidents involving mobile plant within the agricultural, forestry and fishing industries.
Prosecutions and compliance
In 2017, a company was fined $70,000 after a worker was killed while clearing vegetation, otherwise known as scrub pulling, using two bulldozers connected by a chain. In sentencing, the magistrate took into account the company director's remorse as he had been close friends with the worker for many years.
Scrub pulling involves dragging a heavy-linked steel chain between two (usually track type) bulldozers, which move forward across an area of land parallel to each other. The vegetation between the two bulldozers is ripped/pulled out of the ground as the bulldozers drag the chain.
The length and weight of the chain varies, but it can exceed 130 metres and weigh more than seven tonnes. The first bulldozer performing the scrub pulling had mechanical problems and stopped. The second bulldozer continued, pulling the first bulldozer backwards. The worker on the first bulldozer either exited, fell or was ejected from the bulldozer and was run over by it, sustaining fatal injuries. There was no communication system in place between the operators of the two bulldozers.
- How to manage work health and safety risks code of practice 2021 (PDF, 0.65 MB)
- Managing risks of plant in the workplace code of practice 2021 (PDF, 1.57 MB)
- Forest harvesting Code of Practice 2007 (PDF, 1.53 MB)
- Forestry operations guidance material – Safe Work Australia