What is Crystalline silica?
Crystalline silica (quartz) is a natural mineral. It's found in stone products such as reconstituted stone, granite and sandstone. It's also in other building materials such as concrete, bricks and mortar.
How much crystalline silica is present depends on the material. Reconstituted stone can have very high crystalline silica content – up to 95%.
Exposure to crystalline silica dust
When you do things like cut, grind, drill or polish products that contain crystalline silica, it releases very fine dust. Some of the dust is so small you may not be able to see it.
Workers in industries like stonemasonry, construction and the extractives industry may be exposed to crystalline silica dust. Benchtop fabrication workers are at higher risk, because they regularly work with reconstituted stone.
Control the exposure
Use tools with water suppression
Use on tool extraction
Wear a fit for purpose respirator
Silica dust can be harmful when it's inhaled into your lungs. Exposure can lead to deadly diseases, including:
- lung cancer
- kidney disease
- autoimmune disease
Silicosis occurs when crystalline silica dust scars the lungs. It's a serious and incurable disease, with symptoms including shortness of breath, coughing, fatigue and weight loss. In severe cases, silicosis can require a lung transplant or lead to death.
Workplace exposure standard
Safe Work Australia publishes exposure standards for airborne contaminants in the workplace, through its guidance Workplace exposure standards for airborne contaminants (link below).
The exposure standard for respirable crystalline silica dust is 0.05 mg/m3 as a time-weighted average (TWA) airborne concentration over 8 hours.
An 8-hour TWA exposure standard is the average airborne concentration of a particular substance permitted over an 8-hour working day and 5-day working week.
WorkSafe Victoria recommends that employers take a precautionary approach and reduce employees' exposure to below 0.02 mg/m3 as an 8-hour TWA to prevent silicosis and minimise the risk of lung cancer.
Air and health monitoring
Carry out air monitoring
By law, employers must carry out air monitoring if they are not sure if their employees are exposed to levels of silica dust that are above the exposure standard, or they can't work out if there's a risk to employee health without air monitoring.
Ensure an annual health check
Employers must provide health monitoring if exposure to crystalline silica is likely to affect employees' health.
Dust containing crystalline silica can have very harmful health effects.