Now in effect: California’s new silicosis prevention law

Sacramento, CA — A new California law aimed at curbing cases of silicosis among workers who cut, grind, polish and drill stone countertops is now in effect.

Silicosis is a severe and incurable – but preventable – lung disease caused by breathing in respirable crystalline silica. The substance is a common hazard for stone workers and coal miners. 

Signed in October by Gov. Gavin Newsom (D), the Silicosis Training, Outreach and Prevention (STOP) Act (S.B. 20) bans the use of dry cutting for stone countertops and requires worker training, among other provisions. Employers in the state must submit proof of that training to the Division of Occupational Safety and Health by July 1.

The law essentially codifies the California Occupational Safety and Health Standards Board’s silica rules, approved in December 2024. That action took place one year after the state issued an emergency temporary standard in December 2023.

Citing data from the state’s Department of Public Health, the STOP Act text states that 370 workers had silicosis as of Aug. 22. Also, “At least 21 workers have died, most of whom were 30 to 40 years of age, inclusive, and at least 44 workers have received lung transplants.”

Sen. Caroline Menjivar (D-San Fernando Valley), author of the act, said in a press release issued after the state Legislature passed the bill in September that “since I introduced S.B. 20 (in December 2024), there have been over 120 new silicosis cases identified in California, showing us there is still more work to be done to protect these workers.”

She added: “I knew I had to make this bill a priority in 2025. Also, as the chair of the Senate Health Committee, I have viewed this issue through the lens of our community’s overall health. I am so grateful that we are able to take this next step in the fight to protect our vulnerable workers, and I am anxious to continue to push these efforts even further.”