In July 2019, a worker was crushed to death when manually handling goat carcasses. He was trapped by a hydraulically operated stainless-steel bucket.
A conveyor belt moves and loads carcasses into a hydraulically operated stainless-steel bucket. Once the bucket is loaded, it raises up and tips the carcasses into a ‘de-hairer’ machine.
The conveyor belt stopped when the ‘de-hairer’ feeder machine failed, and workers manually unloaded carcasses into the stainless-steel bucket. The worker was standing in the bucket when it unexpectedly began to raise. As the 46-year-old attempted to step out of the bucket, he slipped and became wedged under a steel lip on the machine. The bucket dropped to its ‘home’ position, crushing the man across the upper torso and stomach area.
Investigations are continuing.
Preventing a similar incident
Equipment that uses hydraulics to assist in its movement has the potential to cause serious injury or death. It is used in many industries for trucks and transport, construction plant and equipment, farming machinery, manufacturing equipment and amusement rides. The potential energy in hydraulic equipment can be extremely high as it is used to shift and support large loads, such as animal carcasses.
Serious crush injuries can result from normal movement of the hydraulic equipment, and when the hydraulic systems fail, falling loads or unexpected moving parts are extremely dangerous. Plant arms or equipment can cause injury through rapid or slow movement, without the worker being aware of the danger.
When operating any machinery that uses hydraulics;
- never place yourself or others in a position where you could be crushed if hydraulics fail or they are inadvertently used
- always read the instructions provided by the manufacturer and follow all safety directions
- if a back-up safety system is provided on the plant, ensure it has been correctly installed and always in use before entering a high-risk zone
- if a safety system is not provided on the machine, make sure you use another system that is specified by the manufacturer and is load rated and has adequate strength to safely withstand any loads that could be applied to it
- ensure workers working on, near or under hydraulics are adequately trained and supervised.
Before accessing any parts of plant (including conveyors and associated plant attached to conveyor systems) to clean, maintain or repair, all hazards must be identified and adequately controlled. That means identifying possible hazards such as any hydraulic energy left in the machinery and equipment.
Health and safety risks must be, so far as is reasonably practicable, eliminated. However, if it’s not reasonably practicable to eliminate the risk, then it should be minimised using the hierarchy of controls. This can be done by:
- Isolation – separate the hazardous plant from people (by distance). If this control measure is not possible, the next steps can be considered.
- Engineering controls – include modifications to tools or equipment (e.g. installing guards such as shrouds to prevent inadvertent contact with control levers or buttons).
- Guarding increases safety for operators and others involved in the normal use, servicing and maintenance of machines.
- Redesigning the electrical system to allow for the installation of emergency stop buttons within easy reach of operators of plant.
If any risk remains, it must be minimised by implementing administrative controls, for example lockout – tagout procedures.
The following is an overview of the lockout tagout process:
- shutdown the machinery and equipment
- identify all energy sources and other hazards
- identify all isolation points
- isolate all energy sources
- de-energise all stored energies
- lockout all isolation points
- tag machinery controls, energy sources and other hazards
- test by ‘trying’ to reactivate the plant without exposing the tester or others to risk (failure to reactivate ensures isolation procedures are effective, and all stored energies have been dissipated).
Where the conveyor or any associated plant attached to the conveyor system cannot be isolated, a process or procedure should be in place to prevent inadvertent activation during cleaning or maintenance. All affected workers and persons must be consulted and trained in the process or procedure implemented at the workplace.
Other examples of administrative controls include; training and supervision, using warning signs and providing a system to report faults to ensure maintenance of plant.
|Note: Administrative control measures rely on human behaviour and supervision, and used on their own, tend to be least effective in minimising risks.|
The control measures that are implemented must be reviewed and, if necessary, revised to make sure they work as planned and no new hazards have been introduced by the control measures.
From 2014-15 to March 2018-19, 261 entrapment-related workers’ compensation claims were accepted relating to workers being trapped by moving machinery or equipment in the meat manufacturing industry.
During the same period, WHSQ was notified of 62 events involving an entrapment-related incident at an abattoir. Of these, 42 events (67%) involved injury or illness requiring a person to have immediate treatment as an in-patient in a hospital.
Prosecutions and compliance
In 2017, a company was fined $215,000 when an experienced plant operator was fatally crushed in a raised scissor hoist (part of a large piece of plant known as an Interleaver Phaser Machine or “IPM”). It was not established how the worker accessed the hoist, but it was possible he climbed through a gap in a handrail, bypassing mechanisms which would lock-out/isolate the hoist. Circumstances suggested he did this to access a limit switch which would sometimes fail when large boards were fed into the IPM.
Managing risks of plant in the workplace Code of Practice 2013 (PDF, 1.07 MB)
How to manage work health and safety risks Code of Practice 2011 (PDF, 1.37 MB)
Hydraulics safety brochure (PDF, 896 KB)
AS4024.1603 Safety of Machinery