WASHINGTON — OSHA's crystalline silica standard, which limits worker exposure to silica dust generated during construction and restoration activities including concrete grinding, drywall cutting, and masonry work, has been in effect since 2017 — but enforcement has intensified in recent years, and restoration contractors who are not in compliance face significant penalties.
Crystalline silica is a mineral found in concrete, brick, mortar, and many other building materials. When these materials are cut, ground, or drilled, fine silica dust is generated that can be inhaled and deposited deep in the lungs. Long-term exposure to silica dust causes silicosis — a progressive, incurable lung disease — as well as lung cancer and kidney disease.
OSHA's silica standard sets a permissible exposure limit (PEL) of 50 micrograms per cubic meter of air as an 8-hour time-weighted average, and an action level of 25 micrograms per cubic meter. Employers must implement engineering controls — including wet methods, local exhaust ventilation, and enclosed cabs — to reduce silica exposure below the PEL.
For restoration contractors, the most common silica-generating activities include concrete grinding and cutting, drywall cutting and sanding, and demolition of masonry structures. Contractors must assess the silica exposure risk for each task and implement the appropriate engineering controls and respiratory protection.
OSHA has developed a table of specified exposure control methods for common construction tasks that, if followed, are presumed to reduce silica exposure below the PEL without the need for air monitoring. Restoration contractors who follow the table methods are in a strong compliance position.
