Respirable crystalline silica (silica dust) – very small particles at least 100 times smaller than ordinary sand – is created when cutting, sawing, grinding, drilling and crushing stone, rock, concrete, brick, block and mortar. Exposure to silica dust is a significant potential hazard for Laborers, who often engage in tasks that generate it. Silica dust is dangerous when inhaled, which can happen when materials containing silica are sawed, grinded, chipped, hammered or blasted in building, maintenance, highway or demolition operations.
Silica dust inhaled by workers lodges in the lungs and eventually causes silicosis, a deadly and irreversible lung disease. Silica exposure also increases risk for lung cancer, chronic obstructive pulmonary disorder (COPD), kidney disease and tuberculosis. Depending on the level of exposure, symptoms of silicosis can develop anywhere from months to years later.
The risks of even slight exposure to silica are serious, so it’s important to limit workers’ exposure. OSHA requires engineering controls, such as water sprays and local exhaust ventilation, to reduce dust at the source. When these methods alone aren’t enough to reduce exposure below the PEL, employers must supplement these controls with the use of respirators. Using tools with integrated water delivery systems for cutting, chipping, drilling, sawing and grinding is a best practice that ensures the use of wet methods. Employers can also adjust work practices to limit exposure (e.g., working downwind, limiting task time, rotating responsibilities) and allow workers to voluntarily wear N95 respirators.