851 Silica Dust Safety in Construction

Best Practices for Grinding

• Handheld grinders for uses other than mortar removal: There are two primary control strategies used to reduce exposures:
• When used outdoors only, use grinders equipped with integrated water delivery systems that continuously feed water to grinding surfaces, or
• Use grinders equipped with commercially available shrouds and dust collection systems.

When the requirements of either of these two strategies are met while working outdoors, no respiratory protection is required. If working indoors or enclosed areas for more than 4 hours per work shift, use APF 10 respiratory protection.

• Walk-behind milling machines and floor grinders: Two strategies for this equipment may be used:
• Use machine equipped with integrated water delivery system that continuously feeds water to the cutting surface, or
• Use machines equipped with dust collection system recommended by the manufacturer.

When used indoors or enclosed areas, use a HEPA-filtered vacuum to remove loose dust in between passes.

When the above requirements for walk-behind milling machines and floor grinders are met, respiratory protection is not required.

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