Why is Silica Hazardous?
Silica, often referred to as quartz, is a very common mineral. It is found in many materials common on construction sites, including soil, sand, concrete, masonry, rock, granite, and landscaping materials.
The dust created by cutting, grinding, drilling or otherwise disturbing these materials can contain crystalline silica particles. These dust particles are very small. You cannot see them. This respirable silica dust causes lung disease and lung cancer. It only takes a very small amount of airborne silica dust to create a health hazard.
Recognizing that very small, respirable silica particles are hazardous, the Occupational Safety and Health Administration (OSHA) regulation 29 CFR 1926.55(a) requires construction employers to keep worker exposures at or below a Permissible Exposure Level (PEL) of 0.1 mg/m3 (click here to learn more about the PEL). The National Institute for Occupational Safety and Health (NIOSH) has a lower Recommended Exposure Level (REL) of 0.05 mg/m3. (See Step 2 of the “Create-A-Plan” section of this website for information on using air monitoring to measure exposure levels.)