Relevant History

On December 29, 2023, the California Occupational Safety and Health Standards Board instituted an emergency regulation to address occupational exposure to respirable crystalline silica. This regulation addressed additional safety requirements for businesses involved in cutting engineered stone, improved monitoring for workplace sites, and increasing the ability for workers to report non-compliant employers. These emergency regulations became permanent in February 2025.

The growth in cases of silicosis from exposure to engineered stone created a flurry of inspection activity in California. In 2024 alone, Cal/OSHA conducted 85 inspections related to silica exposure.¹ These inspections resulted in 26% of the shops inspected receiving Orders Prohibiting Use (OPUs), which temporarily shut down equipment or processes that pose immediate safety risks until the issues are fixed. Additionally, citations were issued in approximately 95% of the closed inspections, with 53 out of 56 resulting in violations. In its most recent statement supporting making the emergency regulations permanent, Cal-OSHA noted the unique nature of the stone-countertop industry and in particular that the workers are particularly vulnerable, because they are not represented by a labor union and face the possibility of retaliation if they report workplace hazards to Cal-OSHA. Further, only 7% of the employees in the industry received workers’ compensation.

Once the regulators were deeply involved in this issue, legislation supporting this activity was bound to follow.

Changes in Legislation

During recent sessions of the California legislature, several bills have been introduced to address the evolving fabrication shop working conditions and develop protocols for the proper handling of engineered stone. In the 2023-2024 session, Assembly Bill 3043 – also known as the Silicosis Prevention Act – was introduced by Assemblywoman Luz Rivas. This bill was withdrawn but was a template for the current session.²

Senate Bill 20

A nearly identical bill was introduced this session by Senator Caroline Menjivar. Senate Bill 20, referred to as the Occupation Safety: Fabrication Activities on Slab Solid Surface Products, (“SB 20”) also substantially affects the manufactured stone industry by banning dry fabrication activities, imposing licensing requirements for employers and workers, and implementing a public database for violations and other state enforcement actions. The proposed bill addressed the following impositions on the suppliers and manufacturers of stone slab products commonly used in residential kitchen countertop installation or customization. These regulatory changes included:

• Banning dry stone fabrication or cutting;
• Requiring wet fabrication methods, such as using constant running water on the entire surface being cut and the cutting equipment, water jet cutting, or submersion cutting;
• Licensing requirements for fabrication shops, requiring compliance with state occupational health standards and imposing violations for instances of noncompliance;
• Certification requirements for fabrication workers under an authorized training curriculum;
• Prohibiting suppliers of slab products from working with unlicensed fabricators;
• Creation of a public database tracking licensing, violations, and other enforcement actions;
• Reporting requirements for state agencies on silicosis statistics, worker safety assessments, and the effectiveness of the new regulatory structure.

Currently, SB 20 passed out of the Senate Appropriations Committee in mid-April, but because the costs of the resulting programs are still unknown, the bill has not moved further and is laid over on the suspense file. If the bill is passed, it will require that on or before July 1, 2026, the Department of Industrial Relations in the Labor and Workforce Development Agency to adopt a training curriculum regarding the safe performance of fabrication activities on stone slab products that meet specific requirements, including classroom instruction. Beginning July 1, 2027, the bill would require individuals, including an owner or operator of a slab surface product fabrication shop, to have completed the training curriculum before fabrication activity or employment. The bill would further require, beginning July 1, 2027, that the Department grant a 3-year certification to a fabrication shop that demonstrates satisfaction of specified criteria involving workplace safety conditions.

Current Regulations and Looking Forward

The new regulations require employers to engage in exposure assessments for each employee who may reasonably be expected to be exposed to respirable crystalline silica. If the monitoring is below a level where employers must act to protect employees by shutting down activity, then there is no more need for monitoring.³ If the activity is a potentially high-exposure task, such as crushing, cutting, or drilling engineered stone, then testing must be done at least every twelve months.⁴ Further, employers must develop a written exposure control plan outlining tasks where exposure to silica dust may take place, practices to limit employee exposure to silica dust and housekeeping and hygiene rules where employees may be able to wash and were silica dust can be collected and disposed of after each session.⁵ Finally, employers must engage in employee training on how to avoid silica dust and best practices for avoiding inhalation of silica dust. It is vital that businesses comply with these new regulations and continue to follow and adapt to the quickly developing and changing laws and regulations within the industry.⁶

1. It is clear that many businesses are not prepared to address changing worker conditions in light of increased use of engineered stone. ↩︎
2. A deeper discussion of this bill can be found at the Husch Blackwell blog. ↩︎
3. An employer no longer has to test when the employer has objective data demonstrating that employee exposure to respirable crystalline silica will remain below 25 micrograms per cubic meter of air (25 μg/m3) as an 8-hour time-weighted average (TWA) under any foreseeable conditions. 8 CA ADC 5204(a)(2). ↩︎
4. 8 CA ADC 5204(d)(2). ↩︎
5. 8 CA ADC 5204(f). ↩︎
6. 8 CA ADC 5204(l)(4). ↩︎