There have been recent growing concerns regarding the inhalation of crystalline silica dust in the California stone countertop industry, with attempts by the California State Legislature to enact regulations improving the occupational safety of workers fabricating stone slab products.¹, ² As this proposed legislation has developed, multiple studies have been conducted regarding safety measures that can be implemented for stone fabrication workers. Notably, some of those studies have revealed that effective methods to reduce occupational exposure to silica dust during fabrication exist and are feasible to implement by employers. While the research in the California stone countertop industry is still ongoing, the National Institute for Occupational Safety and Health (“NIOSH”) has found that combining engineering controls and safer work practices would help greatly reduce the risk of harmful exposure to respirable silica dust.³, ⁴ Employers following this combination suggested by NIOSH in 2024 should make it feasible to safely work with stone slab products in California.

However, NIOSH has found there has been history of widespread employer noncompliance with California’s Title 8 standards that regulate the stone fabrication industry.[4] This widespread noncompliance is exactly why it is critical that the recommended safety measures are properly implemented by employers to keep trained employees safe. A failure to comply renders safety measures ineffective. For example, NIOSH recommends different types of respirators depending on the concentration of silica dust in the air, which employers can find through site testing.⁵ Particulate respirators can vary widely in their characteristics such as the type of filter (e.g., N, R, or P filters in the 95, 99, or 100 ranges), amount of face coverage (quarter mask vs. full face coverage), power, air-purifying, supplied-air, and positive pressure respirator safety measures. [7] In its recent survey of stone fabrication shops across California, some of the safety measures that Cal/OSHA has also found to be effective in lowering the exposure to silica dust in this industry include: 1) proper ventilation; 2) vacuums; 3) wet fabrication methods; 4) plumbing; 5) using respirators and other personal protective equipment. [3, 4] Of course, improving employee safety training was also found to be a measure that would reduce exposure to silica dust. [3, 4] Notably, these measures are not only practical, but are also cost-effective for employers to implement with no significant adverse economic impact to the industry in California.⁶, ⁷

The widespread noncompliance of employers that was discovered by Cal/OSHA naturally results in employees being less safe, as it would in any industry. As early as January 2019, Cal/OSHA initiated a Special Emphasis Program (“SEP”) for this industry in order to enforce compliance with California’s developing regulations. [4] The very creation of this SEP shows how widespread that noncompliance really was. As part of the SEP, Cal/OSHA began identifying active stone fabrication sites, conducting air sampling of workers at those sites, and determining whether any exposures to respirable silica were above permissible limits. Cal/OSHA estimated that out of 4,000 shop workers in California, about 3,000 – or 75% were likely exposed to respirable silica at or below permissible limits. [4] Thus, an estimated 25% of employers were found to have likely exposed employees to impermissible levels of respirable silica dust, a result that could have been avoided if those employers had followed Cal/OSHA and California’s regulations.

Owners of fabrication shops that do not meet their duty to be aware of the applicable regulatory safety standards and recommendations may place their employees and anyone present at their worksites at risk of exposure to unsafe levels of silica exposure. Cal/OSHA found that while workers in the stone countertop industry reported high levels of employer non-compliance with regulations pertaining to the inhalation of crystalline silica dust, workers in this industry are generally not represented by a labor union and are subject to retaliation for reporting workplace hazards. [5] Therefore, some workers are disincentivized from filing formal complaints with regulatory agencies like Cal/OSHA even if their employers do not follow regulations and/or fail to implement safety measures for their employees.

This landscape is still developing, but looking forward, Cal/OSHA has notably rejected a proposal to impose bans on types of stone slab products given the concern that such bans could incentivize the industry to simply move to other states where there is no ban is in place. Such a ban may also result in the rise of illegal and unregulated fabrication shops to skirt Cal/OSHA’s requirements. [5][6] Thus, instead of imposing a blanket ban on the industry, the agency is recognizing the continued need to study and explore the implementation of further cost-effective regulations. This way, the agency can keep a watchful eye on employers in the the stone countertop industry to ensure that exposure levels remain safe.

1. California Assembly Bill 3043, introduced on February 16, 2024, withdrawn on July 3, 2024. ↩︎
2. California Senate Bill 20, introduced on December 3, 2024. ↩︎
3. Qi, C. and A. Echt. Engineering Control of Silica Dust from Stone Countertop Fabrication and Installation – Evaluation of Wetting Methods for Grinding. Comprehensive Report. EPHB Report No. 2024-DFSE-1618. Washington, DC, USA. June 2021. https://www.cdc.gov/niosh/surveyreports/pdfs/2021-DFSE-710.pdf. ↩︎
4. Qi, C. Investigation of Ventilation Engineering Controls for Stone Countertop Fabrication. Comprehensive Report. EPHB Report No. 2024-DFSE-1618. Washington DC, USA. February 2024. https://www.cdc.gov/niosh/surveyreports/pdfs/2024-DFSE-1618.pdf. ↩︎
5. The National Institute for Occupational Safety and Health (NIOSH) Pocket Guide to Chemical Hazards. Silica, crystalline (as respirable dust). https://www.cdc.gov/niosh/npg/npgd0684.html. ↩︎
6. State of California – Department of Industrial Relations, Occupational Safety and Health Standards Board. Initial Statement of Reasons, California Code of Regulations, Title 8, General Industry Safety Orders Section 5204 Occupational Exposures to Respirable Crystalline Silica. htps://www.dir.ca.gov/oshsb/documents/Respirable-Crystalline-Silica-Non-Emergency-ISOR.pdf. ↩︎
7. State of California – Department of Industrial Relations, Occupational Safety and Health Standards Board. Public Hearing Notice. Published May 3, 2024. https://www.dir.ca.gov/oshsb/documents/noticeJun2024-Respirable-Crystalline-Silica-Non-Emergency.pdf. ↩︎