OSHA Previews Findings from Inspections Focused on Silica in Engineered Stone
Many workplaces in the engineered stone fabrication and installation industries inspected by OSHA during the last year had not properly conducted exposure assessments for silica, according to a new hazard analysis published by the agency. The document outlines OSHA’s findings from these workplace inspections, which stemmed from an enforcement and compliance initiative launched in September 2023 to help protect workers in stone establishments where their work can expose them to high levels of silica dust. Engineered stone is of particular concern because it can contain more than 90 percent crystalline silica content, far higher than the 10 to 45 percent typical with granite, according to a hazard alert (PDF) from OSHA and NIOSH.
From the launch of the initiative until July 8, 2024, OSHA conducted 204 targeted inspections in the engineered stone industries—160 inspections of companies in cut stone and stone product manufacturing and 44 of merchant wholesalers of brick, stone, and related construction material—as well as another 42 unprogrammed inspections. OSHA says it issued violations in 149 of these inspections and identified 68 overexposures to respirable crystalline silica.
The OSHA document contains examples of issues employers have experienced when attempting to control worker exposures to respirable crystalline silica. In one case, a marble and granite company was incorrectly using table 1 from OSHA’s respirable crystalline silica standard for construction for compliance. While the table allows the use of wet cutting methods for exposure control in construction, OSHA explains that the standard for general industry “prohibits using the construction table if the task is performed regularly in the same environment and conditions” such as in the company’s shop. During a different inspection of a brick manufacturer, the agency identified several overexposures to respirable crystalline silica among saw operators, including overexposures up to 373 µg/m3, which OSHA stresses is more than seven times the permissible exposure limit for silica. The manufacturer had also implemented wet cutting methods as part of its workplace controls, but it was recycling the cutting water, which the agency notes could concentrate contaminants including silica.
The most common violation identified by OSHA during its recent inspections of stone establishments was failure to implement written hazard communication programs. Other frequent violations included missing elements of respiratory protection programs and lack of medical examinations for workers wearing respirators.
Further details can be found in OSHA’s hazard analysis document (PDF).
Related: On July 1, Australia became the first country to prohibit the use, supply, and manufacture of all engineered stone. A SynergistNOW blog post published last year discusses engineered stone, silica, and the precautionary principle. An article published in 2022 in The Synergist focuses on engineering controls for respirable crystalline silica hazards.