On July 31, 2026, Cal/OSHA convened a stakeholder advisory meeting to gather input on a proposed emergency regulation addressing the fabrication of engineered stone countertops and similar products containing more than one percent crystalline silica.
The meeting followed the Occupational Safety and Health Standards Board’s partial approval of Petition 609 and continued the emergency-rulemaking process discussed in RHP Risk Management’s June meeting update.
Importantly, the July 31 meeting was an advisory session, not a formal vote or rule-adoption meeting. Cal/OSHA did not approve a prohibition, establish an effective date, or adopt regulatory language during the July 31 emergency rulemaking meeting. Instead, the agency sought stakeholder feedback on how a potential prohibition could be structured and implemented.
Transition Periods, Contracts and Existing Inventory
A substantial portion of the July 31 discussion focused on the transition period. Occupational-health researchers reported that most of the nine fabrication shops interviewed considered a 12-month transition workable, while worker-health advocates supported an immediate or relatively short transition and a firm cutoff to limit continuing exposures. Fabricators and construction-industry representatives requested more time because of existing inventory, disposal costs and long-term project commitments.
Industry representatives, however, generally requested longer periods, often two years or more, to address existing inventory, customer contracts, showroom displays, supplier relationships and construction projects already underway. Participants also raised questions about disposal costs and whether businesses should receive assistance for inventory that could no longer be fabricated or sold in California.
No transition period was selected.
Single Cutoff Date Versus Gradual Phaseout
Participants also discussed whether California should establish one firm prohibition date or gradually reduce the amount of covered engineered stone entering the market.
Several stakeholders from different perspectives favored a single cutoff date. Worker-health advocates argued that a prolonged phaseout would extend harmful exposures, while some industry representatives said a gradual phaseout could be difficult to administer and might encourage businesses to discount and rapidly fabricate remaining inventory.
Cal/OSHA emphasized that the phaseout concepts presented during the meeting were examples for discussion and that no decision had been made.
Fabrication, Installation and Future Technologies
Another unresolved issue was whether the proposed emergency regulation should cover only fabrication-shop activities or also cutting, trimming and other fabrication performed during installation.
Participants noted that on-site work may involve different employers, working conditions and exposure controls. Some urged Cal/OSHA to include installation-related fabrication to prevent work from simply shifting outside regulated shops. Others cautioned that a broad restriction could affect construction projects and activities involving prefabricated products.
The meeting also considered whether future technologies, such as fully enclosed, automated fabrication systems, could qualify for an exemption. Some participants supported a performance-based pathway for demonstrably protective technology, while others recommended relying on California’s existing variance process rather than creating a broad exemption.
Showrooms, Product Documentation and Testing
Cal/OSHA explored upstream controls that could reduce demand for covered products before they reach fabrication shops. Discussion included whether showrooms, retailers, distributors and manufacturers should stop displaying or promoting products containing more than one percent crystalline silica.
Stakeholders also discussed:
- Manufacturer or importer certifications identifying silica content
- Standardized labeling and safety data sheets
- Periodic third-party verification
- X-ray diffraction and other appropriate analytical testing
- Documentation that employers could rely upon without testing every slab
- Worker notification and training requirements during a transition
Participants generally cautioned against placing the primary testing burden on small fabrication shops. Several recommended that reliable product information originate with manufacturers, importers or distributors and remain traceable throughout the supply chain.
What Happens Next in Cal/OSHA’s Engineered Stone Silica Emergency Rulemaking?
Cal/OSHA stated that it would review the meeting testimony and written comments, prepare draft regulatory language for stakeholder review, consider additional feedback and then advance an emergency regulatory proposal through the Standards Board process.
The Occupational Safety and Health Standards Board’s next monthly meeting is scheduled for August 20, 2026, at 10:00 a.m. in Alameda. Currently, the posted agenda does not list engineered stone or crystalline-silica rulemaking as an item for consideration or action.
Additional advisory meetings are anticipated to address scientific, technical and implementation issues, although Cal/OSHA has not announced any dates. Emergency rulemaking remains the agency’s immediate priority.
California continues to move toward significant restrictions on engineered-stone fabrication, but the scope, transition period, exemptions, documentation requirements and effective date remain under development. Employers should continue complying with existing silica requirements while monitoring the Cal/OSHA advisory-meeting webpage and the Standards Board meeting schedule for draft language, advisory-meeting announcements and future agenda items.
RHP Risk Management Silica Consulting Services
RHP Risk Management’s Certified Industrial Hygienists, public-health scientists and safety professionals provide scientifically rigorous, well-documented and defensible silica exposure assessments, air monitoring and regulatory-compliance support. Our services include engineering- and work-practice-control evaluations, respiratory-protection programs, hazard communication, compliance planning and technical support.
Contact RHP Risk Management to learn how our industrial-hygiene professionals can help your organization evaluate silica exposures, prepare for California’s evolving requirements.