Safety Tips: Preventing Grinder Injuries

Part of a regular series on safety issues

Grinders are commonly used tools, but operators often do not take the time to consider the tremendous potential that these tools have to cause severe injuries. To help overcome this, we’ve put together this primer on best practices for grinder safety.

Attire

Employee attire can provide some basic protection against sparks and debris, so many workplaces have uniforms for their workers who used these tools extensively. If your employer doesn’t provide you with a uniform, you should wear boots (preferably steel-toed if heavy objects are being moved or worked on), and clothing with a high thread count that is made from natural materials (e.g, cotton, linen, denim, etc.). You should also tuck in shirts in and secure all jewelry, bandanas, and hair to prevent these items from being caught in the grinder. At thousands of revolutions per minute, a grinder can grab a loose item and cause serious injury faster than you can react.

Personal Protective Equipment

Of course, clothing itself does not provide you sufficient protection when using grinders, so you should also use personal protection equipment (PPE). You should always wear ear plugs and safety glasses or goggles, no matter what materials you’re grinding or what type of grinder or grinding wheel you’re using. For increased safety, you can wear a face shield, too.

You may also want to wear gloves, depending on the type of grinder you’re using. Gloves are a necessity for angle grinders because they protect your hands from sparks and debris. However, for abrasive belt grinders, bench grinders, pedestal grinders, and surface grinders, the risk of catching the glove on the wheel and causing an amputation outweighs the benefit of hand protection.

You should also wear a respirator, particularly when using conventional abrasive grinding wheels, which give off harmful particles as they wear down. A diamond superabrasive grinding wheel, which does not emit these harmful particles, is a safer choice.

Before You Grind

So you’ve geared up for safety! But you’re not done yet. You still have steps that you need to take to ensure safe operation of your grinder and grinding wheel. Before operating any tool, ensure that the work area is clean and well-lit. This eliminates extraneous hazards and ensures that the operator can see properly when handling potentially dangerous tools. For grinders, it is also important to remove fire hazards, such as flammable chemicals or high concentrations of sawdust, since the sparks from a grinder can ignite these.

You should also examine your grinder for damage before use. This includes looking at the housing, guards, electrical cords, and plugs to ensure that they are in safe operating condition for use. The guard must cover half of the grinding wheel and should be between you and the grinding wheel to protect you from sparks and debris. In addition, when using an angle grinder, you should ensure that the right angle handle is in place and secure. This allows you to use two hands so that, if the grinder kicks back, you have a much better chance of maintaining control.

The grinding wheel itself should also be examined for flaws both visually and using a “ring test” before mounting it to the tool. To perform a ring test, tap the wheel gently with a nonmetallic object and listens to the sound it makes. A clear sound indicates an undamaged wheel, whereas a dull or dead sound means the wheel is cracked and should not be used.

Finally, make sure that the grinding wheel is mounted tightly and properly to the grinder and that the grinding wheel’s rated speed rating is at least as high as the grinder’s rated speed. Then hold the grinder so that it faces away from people, and run the tool without a load for approximately one minute. Most damaged abrasive wheels will break apart during this no-load test. When using a high-quality superabrasive diamond wheel, this no-load test is unnecessary.

Before starting to grind, you should also be sure that there are not people in the ”line of fire” – the area where a wheel fragment might fly should the grinding wheel fail. This shrapnel is a serious danger to the operator and anyone nearby. Another “line of fire” consideration is ensuring that people are not in an area where sparks might land.

After You Grind

Safety considerations should also be paramount at the end of the grinding process and when changing grinding wheels. Because grinders operate at such high speeds, you should maintain control over the grinder and prevent anyone from touching the wheel as it winds down to a stop. When changing the wheel, make sure that the grinder cannot be accidentally turned on. For an angle grinder, this simply means unplugging it or removing its battery. For larger grinders and grinding machines, this will require properly locking out or tagging out procedures.

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