Noise management data sheets: circular saws (handheld)
Contents
1. Introduction
Hand held power circular saws are used for rapid cutting of timber on site. The noise levels of power saws can exceed 110 dB(A). Hearing protection is required as the exposure standard can be exceeded in a short period of time.
2. Maintenance
Maintain tool in good operational condition. These tools normally have a brush type electric motor that runs at high RPM. The noise levels produced by the tool relate directly to the condition of the motor and blade.
- Inspect and replace any worn bearings and brushes. Excessive sparking in the motor could indicate worn brushes.
- To test for wear in the main shaft bearings, grab the saw blade and attempt to wiggle it from side to side. There should be very little play.
- Worn bearings on this tool can create a safety hazard. Increased play in the main shaft causes the blade to jam in the cut.
- Tighten any loose parts such as blade covers.
- Keep blades sharp.
- Use the correct type of blade with teeth spacings to suit the task.
3. Noise control
- Use quieter saw blades
- Use saw away from main work areas, or perform sawing operations in an isolated room.
4. Operator control
- Feed in blade gently, letting the blade cut at its own speed. Keep the bed of the saw flat against the wood and avoid twisting blade. Clamp work to saw stool if possible. Use gentle pressure and allow the blade more time to cut. This also extends blade life.
- If noise level of saw is known, schedule work so not to exceed the daily exposure standard.
5. Alternatives
- Investigate alternative methods for performing the work. A band saw may be suitable or a large docking saw with an induction motor may produce less noise. For small jobs use a sharp hand saw to lessen noise exposure.
- If the noise levels produced by the saw are less on softwoods than hardwoods, use softwoods if practicable.
Adapted from the Noise Control Manual for Schools with the permission of the Education Department of Western Australia.