Hand tools
Using hand tools can injure the wrist, elbow and shoulder.
Tools that cause health problems are not necessarily of non ergonomic design - they may be well designed but used excessively.
Using tools may require awkward or static postures and forceful exertions. For example, working in cold conditions leads to a loss of sensitivity in the fingers and may lead result in a more forceful grip. Alternatively, you may have to bend your wrist to use a tool, or use a very firm grip to hold it steady. Some tools are heavy, or have a wide grip span. Some send shocks to the wrist and hand, while others press into the hand to cause contact stress.
While gloves protect hands and fingers, they increase the muscular effort in using a hand tool by about 20% (or more if the gloves do not fit correctly).
Ways to control hazards
- Assess the risks of using certain hand tools. Consider size, weight, type of handle and the grip needed.
- Buy the right tool for the job. Purpose-made tools should be light and comfortable to use, and should not require excessive force.
- Buy tools that can be used in either hand (this provides for left-handed people).
- When buying heavy tools, choose tools where the heaviest part is not in front of the wrist, and where the weight supported by the worker is as low as possible for the type of tool.
- Alter the use of heavy hand tools. For example, suspend heavy tools that are used repeatedly for the same task in the same place; or use counterbalancing equipment for repetitive work where tools have to be held away from the body.
- Use power tools where possible to reduce the muscular effort needed.
- Choose trigger tools where the trigger is:
- easy to activate in either hand
- at least 5cm long (so it can be activated by several fingers)
- supported by a trigger lock if you need to sustain the trigger grip for more than 30 seconds at a time.
- Choose tools with handles that:
- are cylindrical (about 4cm in diameter)
- are well designed and fit the hand
- have a span between 6 - 9cm
- allow the wrist to be held straight (in the 'shake hands' position)
- have a comfortable gripping surface (dimpled)
- do not have sharp edges or areas that dig into the fingers or palm of the hand
- are fitted with a guard or stopper (in the case of knives or soldering irons).
- Choose tools with these handle dimensions:
- The grip length should be about 10cm for precision tools and 12cm for power tools.
- Cut-out handles should be about 12cm long by 6cm wide.
- Choose tools with internal damping, or that limit torque reaction:
- Use clutch-type tools, shutoff tools, hydraulic pulse tools, and external devices such as torque bars or articulating bars.
- Use the smallest tool as possible (such as a 10cm angle grinder, not a 20cm grinder).
- Consult with workers about the problems they encounter.
- Review past incident records for tool-related injuries. Try to identify the action or part of the tool responsible for injuries.
- Regularly maintain hand tools.
- Use a vice, clamp or other aids where appropriate. Keep as close as possible to the work.
- Rotate workers to minimise the repetitive use of hand tools for long periods. Train workers in hand tool safety and the importance of minimising hand grip force.
More information on hand tool use is provided in the Manual Tasks Advisory Standard 2000 (now known as a Code of Practice).
