California posts engineered-stone prohibition discussion draft

October 7, 2026

Cal/OSHA posted an engineered-stone discussion draft on September 16, 2026. The agency’s advisory page describes proposed section 5204.1 and changes to sections 5204 and 1532.3. Posting a discussion draft does not itself establish an operative prohibition.

APT’s California engineered stone discussion draft tracker record keeps the proposed prohibition separate from the permanent standard.

The proceeding follows a Standards Board petition

The May 2026 DIR announcement reports that the Standards Board granted a petition in part and requested emergency rulemaking. The agency’s September page identifies the draft subject as fabrication and manufacture of artificial stone containing more than 1 percent crystalline silica.

The full discussion draft would start the prohibition 60 days after an OAL effective date that remains a placeholder. A limited exception would allow certain previously purchased, contracted-for or possessed material to be processed while complying with section 5204, ending 180 days after that same placeholder date. Those relative periods are proposed transition terms. September 30, 2026 was the requested comment date.

Keep the discussion separate from the permanent standard

California already has a permanent silica standard under section 5204. A proposed prohibition and the existing task-based controls serve different legal roles. Employers need to identify the operative standard independently of their preparation for a possible future amendment.

APT’s practical interpretation is to retain material-composition records and identify fabrication activities that might fall within the proposal’s stated subject. Those records can support a later comparison with adopted text if the proceeding advances.

The proposed construction text would apply section 5204.1 to onsite fabrication but exclude onsite installation, maintenance and repair from that section. The draft defines installation as fitting and securing previously fabricated slabs, including only minor onsite adjustments. These proposed distinctions do not remove other applicable silica controls. The agency still presents this material as a discussion draft in the source checked October 7. No adopted commencement date is established here.

Find related developments in the industrial hygiene regulatory tracker.