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What safety precautions should you follow when using a portable grinder?

  • Guards must be provided and adjusted to protect you. Replace damaged guards because if an abrasive wheel breaks while rotating, it can cause a serious injury.
  • Clean and service grinders according to manufacturers' recommendations. Record all maintenance for grinders.
  • Ensure that a machine will not operate when unattended by checking the dead-man (constant pressure) switch.
  • Wear safety glasses, goggles, and face protection to protect against flying particles. Gloves, aprons, metatarsal safety boots, and respiratory protection may be required, depending on the work.
  • Ensure the floor around the work area is clean.
  • Do not use wheels that are cracked or those that excessively vibrate.
  • Do not operate grinder on wet floors.
  • Use both hands when holding the grinder.
  • Keep the power cord away from the grinding wheel and the material being ground.

When and how should you check the speed of the wheel?

  • The maximum speed in revolutions per minute (rpm) is marked on every wheel. Never exceed this speed.
  • Check that the wheel speed marked on the wheel is equal to or greater than the maximum speed of the grinder.
  • Measure the speed of any new machine. Take several readings.
  • Measure the speed of governor-controlled air-driven grinders after twenty hours of use or every week, whichever comes first. Measure the speed after any repairs.
  • Measure the speed of electrically driven grinders monthly and after repairs.

What should you do when using portable grinders?

  • Check that grinders do not vibrate or operate roughly.
  • Use racks or hooks to store portable grinders.
  • Stand away from the wheel when starting grinders. Warn co-workers to do the same.
  • Inspect all wheels for cracks and defects before mounting.
  • Ensure that the mounting flange surfaces are clean and flat.
  • Ensure the wheel guard is in place while operating the grinder.
  • Use the mounting blotters supplied.
  • Run newly mounted wheels at operating speed for 1 minute before grinding.
  • Wear appropriate eye, ear and face protection. Use other personal protective equipment or clothing, as required under the circumstances.

What should you avoid when using portable grinders?

  • Avoid using grinders near flammable materials.
  • Do not clamp portable grinders in a vise for grinding hand-held work.
  • Do not use any liquid coolants with portable grinders.
  • Do not force wheels onto a grinder that is the wrong size or change mounting hole sizes.
  • Do not tighten the mounting nut excessively.
  • Do not put the grinder on the floor or working surface until the wheel has stopped turning.
  • Do not keep any materials close to the grinding wheel when it is not in use.
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Document last updated on March 1, 2009

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