California workplace safety regulators are pushing an emergency rule that would prohibit the manufacture and fabrication of engineered stone containing more than 1% crystalline silica. The state's Occupational Safety and Health Standards Board is expected to vote on the measure in October. Behind the move is an outbreak of silicosis — an incurable occupational lung disease — among countertop fabrication workers: cases jumped from 31 in 2019 to 631 as of mid-August this year, a twentyfold surge in seven years.
The proposed ban does not touch the quartz countertops already installed in consumers' homes. It targets the production side — manufacturing, cutting, grinding, polishing and installing engineered stone. Crystalline silica dust is released in large quantities only when the stone is cut or polished; the workers who breathe it get sick, while homeowners face no risk. The draft rule, a proposed new Section 5204.1, covers fabrication and manufacture of covered products, with limited exceptions for certain existing orders.
The numbers are stark. One study found California silicosis cases rose from 31 in 2019 to 631 by mid-August this year. Cal/OSHA figures tell a similar story: 52 cases in 2022 versus 531 this year — a tenfold increase in three years. Industry press counts more than 644 confirmed cases of accelerated silicosis since 2022, with 35 recorded deaths and 58 lung transplants performed on industry workers. There is no cure for silicosis; once it takes hold, doctors can only manage symptoms, and severe cases require a transplant.
Engineered stone — crushed quartz bound with polymer resin into an affordable, attractive alternative to natural stone — can contain up to 95% crystalline silica, far more than granite or marble. Cutting and polishing releases ultra-fine respirable particles that lodge in workers' lungs, triggering an aggressive immune response: inflammation, permanent scarring, and progressively failing breathing. Cal/OSHA has concluded that existing controls — wet cutting methods, respirators — are no longer enough, with research suggesting even advanced respiratory protection cannot fully prevent dangerous exposure. The only reliable fix, regulators say, is to take high-silica stone out of fabrication shops entirely.
The victim profile is strikingly concentrated: nearly all men, about half in Los Angeles County, with a median age of 52 — many of them young Latino and foreign-born workers. Enrique Gonzalez, a San Fernando Valley stone worker, is one of them: after years in granite and stone manufacturing, silicosis left him unable to work for two years before he received a lung transplant this past summer. In a new report, Public Citizen said these workers "are dying from silicosis at young ages" and that existing occupational rules "even when strictly followed, fall short in reducing crystalline silica exposures."
California would not be the first. Australia banned engineered stone fabrication outright in 2024, the first country to do so. The California push began with Petition 609 from the Western Occupational and Environmental Medical Association, backed by hundreds of healthcare professionals. Public Citizen is now urging federal action, calling for a nationwide ban on artificial stone above 1% crystalline silica and describing the situation as a preventable public health crisis.
Under the current timeline, the Standards Board could vote as soon as October 2026; the public comment period closed September 30. If adopted, businesses would generally have 60 days to stop manufacturing, shaping and installing covered products. Employers would have to inform workers verbally and in writing that the work is prohibited because of the health risks, post highly visible workplace warnings, and violations could be treated as an imminent hazard. For California's large countertop industry, that means retooling the entire supply chain toward low-silica or natural stone within two months — higher costs, but workers' lungs preserved.