Published May 9, 2024 at 400 × 250 in Here’s Cal/OSHA’s Permanent Proposal on Silica Cal/OSHA says 127 engineered stone workers have developed silicosis, including 13 deaths and 16 who required lung transplants. Cal/OSHA says 127 engineered stone workers have developed silicosis, including 13 deaths and 16 who required lung transplants.