Silica, or silicon dioxide (SiO2), is a mineral that occurs naturally in crystalline or non-crystalline form. The most abundant crystalline form is α-quartz, which is the most common silicate mineral in the earth’s crust. It is found in sand, sandstone, shale and granite. Drilling, crushing, cutting, chipping, breaking, sawing or polishing materials containing crystalline silica can create a large amount of respirable dust.
Silicosis is a lung disease caused by the inhalation of crystalline silica dust. Leading to inflammation and scarring in the form of nodular lesions in the upper lobes of the lungs.
Approximately 2.3 million workers are exposed to respirable crystalline silica in the workplace. This includes 2 million workers in construction and roughly 300,000 workers in general industry, maritime and hydraulic fracturing.
Such jobs include:
Rock drilling, cutting, chipping or polishing
Brick or tile cutting and sawing
Concrete drilling, sawing, grinding and polishing
Stone countertop fabrication
Diatomaceous earth processing
Work on linings of rotary kilns and cupola furnaces