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An OSHA review of 27 grinder accidents found that more than 26% had a fatal ending. Common causes include workers being trapped in the grinding wheel or being hit by flying debris from a wheel explosion.
Machines that use abrasive wheels are powerful and most operate at high speeds, usually several thousand revolutions per minute. If a grinding wheel shatters while it is turning, the fragments from the wheel assembly (including the flange, spindle end, and nut) can travel at more than 300 miles per hour. To ensure that abrasive wheels are safely used in your workplace, know the hazards and how to control them.
Machine Guarding
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Side Guards: These must cover the spindle, nut, and flange, and protect at least 75% of the wheel diameter.
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Adjustable Tongue Guard: This must be present and kept adjusted to within 1/4 inch of the grinding wheel's periphery.
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Strength: Safety guards must be strong enough to withstand the force of a bursting wheel.
Work Rests and Adjustments
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Work Rest: For bench and floor-mounted grinders, the work rest must be rigid, adjustable, and kept within 1/8 inch of the wheel to prevent jamming.
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Guard Adjustment: The adjustable tongue guard should be adjusted to within 1/4 inch of the wheel.
Pre-Use Inspection and Mounting
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Inspection: Before mounting, all wheels must be inspected for cracks or defects and "ring tested". Watch the video Ring Testing Grinding to understand a ring test.
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RPM Check: The machine's spindle speed must not exceed the maximum operating speed marked on the wheel.
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Mounting: Wheels must fit freely on the spindle, and mounting nuts should not be tightened excessively.
Personal Protective Equipment (PPE)
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Eye and Face Protection: Operators must wear safety glasses or goggles and a face shield.
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Other PPE: Depending on the work, gloves, hearing protection, and respiratory protection may be necessary.
Other Safety Requirements
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Clothing: Operators should not wear loose clothing or jewelry and should tie back long hair.
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Maintenance: Ensure the area around the grinder is clean and free of flammable materials.
Click the button below for OSHA's checklist on abrasive wheel machinery.
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