Safe use of grinders on-site

Angle grinders are versatile hand-held tools that are used regularly in the residential construction industry.

Serious incidents can occur when using grinders on-site. The most common causes of injury to operators and nearby workers from angle grinders are:

• Serious harm if caught by cutting/grinding wheel.
  • lacerations from angle grinder kickbacks.
  • lacerations from attachments that break and become projectiles.
• Hearing damage from wheels cutting through material.
• Burns from sparks and workpiece surfaces.

What are some control measures to reduce the risk of injury? 

Here are some control measures to consider when it comes to managing the risks associated with grinders: 

• Determine if an angle grinder is actually the best tool to perform the task, because another tool may be just as, or even more, effective. 
• Prior to purchasing a grinder, look at ones with adjustable handles that can be moved to suit both left and right-handed operators.
• Select a grinder that has an automatic cut-off or dead-man switch as part of the handgrip. This is designed to cut off power as soon as finger pressure is released.
• Only use angle grinders that are an appropriate size for the task. Do not use a grinder that is larger, heavier or more powerful than is necessary, as it is much easier to control a lighter tool.
• Ensure guards are never removed. The guard usually covers half of the disc and is positioned between the disc and the operator. 
• Ensure that the correct type of disc is used for the task being performed. The wrong disc potentially can shatter or ‘grab’ the workpiece causing kickback.
• Regular maintenance and inspection of the grinder and cutting disc by a competent person, as per the manufacturer’s specifications.
• Provide operators with appropriate information, training, and instruction to ensure the grinder is operated safely and competently.

Before use

Before using an angle grinder, check that:

• Guard and handles are secure.
• There are no defects or damage to the disc (a disc that has been dropped may have developed cracks and should not be used).
• Use only the tightening tool supplied by the grinder manufacturer to tighten the disc as other methods can damage the disc and grinder.
• The spindle’s correct disc diameter and central disc hole size are used.
• The correct type of disc is used for the material being cut or ground.
• Make sure the disc is the right way up.

During use

Follow these suggested safe practices when an angle grinder is in use:

• Always ensure that your work area is well ventilated.
• Position the tool so that the power cord always stays behind the machine during operation.
• Make sure the wheel is not contacting the workpiece before the switch is turned on.
• Before using the grinder, test run the tool at the highest no load speed, and stop immediately if any vibration or wobbling occurs.
• Watch out for flying sparks.  Hold the tool so that sparks fly away from you, others, and flammable materials.
• Use two hands to operate the grinder. One hand should grip the handle and dead-man switch (if provided), while the other hand supports the weight of the tool.
• Position the tool so that the power cord always stays behind the machine during operation.
• Allow the grinder to ‘run up’ to operating speed before applying it to the job.
• Hold the grinder against the workpiece with minimum pressure, so the disc does not ‘grab’ and cause it to kickback.
• Keep the grinding disc at a 15 to 30-degree angle to the object. Ensure the workpiece is held firmly, either as part of a larger item or in a bench vice.
• Where possible, keep the work at waist height during grinding.
• Do not put a grinder down until the disc stops rotating.
• Remove the plug from the power point before changing discs.
• Never use a cutting disc for grinding or a grinding disc for cutting.
• Do not touch the workpiece immediately after operation.  It may be extremely hot and could burn your skin.
• Ensure appropriate PPE is worn and review what can get caught in a moving part of the tool. For example: 
• Ensure workers do not wear loose clothing or jewelry.  Long hair is to be securely tied back so nothing can become caught 
• Workers should wear protective clothing such as safety glasses, leather aprons, gloves, face shield (if required), safety boots, RPE (if required) and hearing protection as they will be better protected.

If you’ve got a question about safe grinder use or any other health and safety matter, the HazardCo Advisory Team is here to help. Give them a call on 0800 555 339.