Silica dust is made by cutting, drilling, or grinding products that contain crystalline silica. If the dust particles are small enough, they can cause serious health problems.
Silica
Silica is a naturally occurring mineral and can be either non-crystalline (sometimes called amorphous silica) or crystalline. Crystalline silica is found in stone, sand, gravel, concrete and mortar.
Natural stones, like granite and sandstone, contain varying amounts of silica. For example: granite contains approximately 30% silica, slate contains 40% and sandstone is almost pure silica.
Silica dust is generated by processes such as crushing, cutting, drilling, grinding, sanding, sawing, or polishing products that contain crystalline silica. Silica dust has a range of sizes, from very small to larger particles that can be seen with the naked eye.
Respirable crystalline silica (RCS)
‘Respirable crystalline silica’ (RCS) are silica dust particles that are small enough to breathe in and penetrate deep into the lungs. These dust particles are so small that they cannot be seen under normal lighting or with the naked eye. They stay airborne for long periods of time.
When inhaled, RCS dust particles can travel deep into the lungs causing permanent damage that can lead to serious illness or death. Non-crystalline silica is less toxic but can also cause similar lung damage at high exposure levels.