In August 2018, Missouri On-Site Safety and Health Consultation conducted an initial visit at the request of a stone countertop manufacturer in Fenton, Missouri. The facility wanted to have a better understanding of OSHA's new respirable crystalline silica standard and evaluate employee exposure to the material. Initial sampling performed by consultants found employees' exposure to silica below the former permissible exposure limit (PEL), but above the PEL and Action Level (AL) in the new regulation. Determining the reasons for the overexposure was difficult because the employer had implemented engineering controls and modified work procedures to reduce exposure.

After the initial sampling results, consultants from Missouri Consultation performed air sampling every three months. Each time silica over-exposures were found. It was not until a consultant suggested increasing the distance between employees’ workstations that exposures began to decrease. Because employees were working close together, they were catching the water spray from other employees' wet grinding countertops. As a result of the findings, additional space was created for employee work stations, thus reducing the chances of overexposures. Air monitoring confirmed that all employees were now under the PEL and AL.

The OSHA On-Site Consultation Program offers no-cost and confidential occupational safety and health services to small and medium-sized businesses in all 50 states, the District of Columbia, and several U.S. territories, with priority given to high hazard worksites. Consultants from state agencies or universities work with employers to identify workplace hazards and how to fix them, provide advice for compliance with OSHA standards, train and educate workers, and assist in establishing and improving safety and health programs. On-Site Consultation services are separate from OSHA enforcement efforts and do not result in penalties or citations. However, employers must agree to correct any serious or imminent danger hazards identified in a timely manner. To locate the OSHA On-Site Consultation program nearest you, call 800-321-OSHA (6742) or visit https://www.osha.gov/Consultation.