What is Silica?
Silica is a natural substance
Found in most rocks, sand and clay, as well as in products such as bricks and concrete. Silica is also used as filler in some plastics. In the workplace, these materials create dust when they are cut, sanded, carved etc. Some of this dust may be fine enough to breathe deeply into your lungs and cause harm to your health. The fine dust is called respirable crystalline silica (RCS) and is too fine to see with normal lighting. The quantity of silica contained in stone and other materials varies considerably between different types of stone.
Occupational exposure to RCS can occur in many industries, including:
construction and demolition processes – concrete, stone, brick, mortar; quarrying, slate mining and slate processing potteries, ceramics, ceramic glaze manufacture, brick and tile manufacture, foundries, refractory production, and cutting.
Certain activities create dust containing RCS, such as:
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Grinding, drilling, cutting, sanding, chiseling, blasting polishing, conveying
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Fettling
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Mixing and handling, shoveling dry material rock drilling/breaking/crushing/screening.
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Grit and abrasive blasting, particularly on sandstone
In workplaces, the following can happen:
leaks or spillages cause a build-up of dust containing RCS; dust containing RCS is not cleaned up safely, eg by dry sweeping rather than wet cleaning.
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Clothing and surfaces are contaminated with dust containing RCS;
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Accumulated dust containing RCS is ‘raised’ from the Ground or other surfaces by moving vehicles and people;
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Fine dust remains in the air from work activities.
The effects of dust
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Can be inhaled causing respiratory (e.g. silicosis) and similar health problems.
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Means loss of road/surface material/ballast, leading to re-graveling. Penetrates vehicles, leading to significant maintenance and repair costs. Reduces visibility and safety.
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Creates an unpleasant working environment.
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Leads to unpleasant conditions during events and shows.
Health effects
Breathing in very small ("respirable") crystalline silica particles, causes multiple diseases, including silicosis, an incurable lung disease that leads to disability and death. Respirable crystalline silica also causes lung cancer, chronic obstructive pulmonary disease (COPD), and kidney disease. Exposure to respirable crystalline silica is related to the development of autoimmune disorders and cardiovascular impairment. These occupational diseases are life-altering and debilitating disorders that annually affect thousands of workers across the United Kingdom.
Silicosis
Breathing crystalline silica dust can cause silicosis, which in severe cases can be disabling, or even fatal. When silica dust enters the lungs, it causes the formation of scar tissue, which makes it difficult for the lungs to take in oxygen. There is no cure for silicosis.