Silica Dust Exposure (Table 1 Controls) Toolbox Talk

Key points

• OSHA PEL is 50 µg/m³ TWA over 8 hours, an extremely low limit
• Table 1 lists required controls for 18 common construction tasks
• If you follow Table 1, no air monitoring is required
• Employers must offer a medical exam within 30 days of assignment to workers required to wear a respirator 30+ days/year under the standard
• Wet cutting, LEV, and enclosed cabs are the primary engineering controls
• Housekeeping: no dry sweeping or compressed-air cleaning where it can raise silica dust, except in the narrow cases 29 CFR 1926.1153(f) allows

Hazards to discuss

• Silicosis: irreversible, progressive lung scarring
• Lung cancer (IARC Group 1 carcinogen)
• Chronic kidney disease
• COPD and other respiratory conditions
• Autoimmune disorders (scleroderma, lupus)

Safety precautions

• Use water delivery systems when cutting concrete or masonry
• Operate vacuum dust collection (HEPA) on grinders and drills
• When Table 1 requires a respirator, wear one with at least the assigned protection factor it lists (APF 10 or APF 25)
• Change out of dusty clothes before leaving the work area
• Never eat, drink, or smoke in silica-exposed areas

Discussion questions

1. Which tasks on our site today generate silica dust?
2. What Table 1 controls are we using right now, and are they set up correctly?
3. When was your last silica medical exam?
4. Where are the water hoses and HEPA vacuums located on site?

Summary

Silica dust is invisible but deadly. Follow Table 1 controls for every task, use wet methods or vacuum dust collection, and never skip your respirator. If you see a dry cloud, stop and fix the controls.