Two employees received crush injuries and amputations to their hands after working with unguarded power presses. The guarding was not interlocked with the power press, so the employees were able to continue operating the press without any guarding.
At another workplace an employee was operating a power press to cut out metal parts for manufacturing. The employee was able to use tools to disable the mechanical interlock and operate the press with guarding in the open position. The plant also had an electrical interlock switch which was not operational. The employee placed their hand in the press area of the plant during operation where three fingers were amputated and a fourth finger was partially amputated.
Guarding and safety devices on older power presses may not prevent bodily access to the danger area of the plant and therefore will not meet current Australian Standards.
There are also significant risks during tool changes (die change) on power presses if the guards are not replaced while test strokes are being conducted.
Recommended ways to control risks
Prevent access to danger points and moving parts
Where guarding is used as a control measure, electrical interlocks form an important part of the guarding to ensure the plant is unable to operate without the guarding correctly in place.
A guard can perform several functions: it can prevent bodily access, and contain ejected parts, tools, off-cuts or swath.
Older machinery (eg manufactured in the early to mid-20th century) may not have guards fitted as standard, and will present a risk to the operator if danger points and moving parts can be accessed.
Guarding should be retro-fitted to older machinery and equipment to prevent access to:
- hard surfaces moving together (presses)
- rotating end drums of belt conveyors
- moving augers or auger conveyors
- rotating shafts
- moving parts that do not require regular adjustment
- machine transmissions, such as pulley and belt drives, chain drives and exposed drive gears
- any dangerous moving parts or plant
Where access to the moving part is not required (eg for service and maintenance), the guarding must be permanently fixed, so far as is reasonably practicable. A fixed guard can be permanently applied by bonding agent, welding or secured with one-way screws. A permanently fixed physical barrier provides the highest level of protection against hazards.
Remove and control energy sources during access
Ensure systems are in place to lock out and tag out machinery during cleaning, service and maintenance.
People performing tasks such as maintenance, repair, installation, servicing and cleaning have a higher risk of being killed or injured through inadvertent operation of plant they are working in, on or around.
Accidental start-up or movement of a plant mechanism can occur if control levers or buttons are bumped or knocked, if a short circuit of the control system occurs, when hydraulic or air pressure is released, or when undoing retaining bolts. It is essential that people who work in, on or around plant are not exposed to hazards due to accidental start-up or movement of the mechanism.
Instruction, training and supervision
Provide employees with instructions and training on safe operating procedures. Regularly review procedures, including lock out and tag out systems when undertaking service, cleaning and maintenance.
Under the Occupational Health and Safety Act 2004, employers must:
- so far as is reasonably practicable, provide and maintain a working environment that is safe and without risks to the health of employees and independent contractors
- provide or maintain plant or systems of work that are safe and without risks to health, so far as is reasonably practicable
- make arrangements for ensuring, so far as is reasonably practicable, safety and the absence of risks to health in connection with the use, handling, storage or transport of plant
- provide employees with the necessary information, instruction, training or supervision to enable them to do their work in a way that is safe and without risks to health
- ensure, so far as is reasonably practicable, that people other than employees are not exposed to risks to their health or safety arising from the employer's conduct
Employers and self-employed persons have additional duties under the Occupational Health and Safety Regulations 2017 associated with the use of Plant, including:
- identifying all hazards associated with the use of plant at the workplace, so far as is reasonably practicable
- controlling risks in accordance with the plant hierarchy of control
Specific employer duties also apply where guarding is used as a risk control. For more information on these duties see the Plant compliance code.
AS4024 Safety of machinery, Part 3001: Materials forming and shearing - Mechanical power presses