How to control exposure to respirable crystalline silica (RCS) from natural and engineered stone
If dust controls are not in place, workers in benchtop manufacturing, finishing and installation industries risk exposure to respirable crystalline silica (RCS). Workplace Health and Safety Queensland has a new resource on working safely with silica, showing exactly how tiny an amount of RCS can be to exceed workplace exposure standards (illustration below).
The workplace exposure standard for RCS will be exceeded if the amount of dust you breathe in over a full shift contains more RCS than the amount shown here next to the five cent piece.
Benchtop stones have up to 90 per cent crystalline silica, with potential exposure to workers when cutting, grinding, sanding or polishing both natural and engineered stone. RCS exposure can cause debilitating health effects, including decreased lung function, chronic obstructive lung disease (COPD), silicosis (a form of occupational lung disease) and lung cancer.
Workers can be exposed through benchtop fabrication tasks such as dry cutting, drilling, grinding and polishing stone materials and also from poor cleaning practices, including dry brooming of dust, the use of compressed air to clean dusty clothes, using non-H class HEPA filtered vacuum cleaners or the accumulation of dust within the workplace.
To reduce the amount of dust generated, plan work to make the minimum number of cuts required on each slab and accurately measure a customer’s kitchen to prevent rework or alterations on site.
Even where respiratory protective equipment (RPE) is used, adequate protection may not be provided if the RPE is not suitable for dusts and is not worn when required. Workers have to be fit tested to the type of RPE supplied and the equipment should be stored correctly.
A combination of controls should be used to protect workers and others from RCS during benchtop fabrication. An effective method of dust control during benchtop fabrication is water suppression, however, local exhaust ventilation (LEV) systems used in conjunction with vacuum attached tools may also be suitable. It is important to ensure that when a dust collector or vacuum is used, that it is H class rated (for high hazard dusts like silica) and fitted with a HEPA filter.
The new resource, with more information on good housekeeping practices, using RPE and training, is at worksafe.qld.gov.au.
For more information on how to manage RCS risks:
Silica – Technical guide to managing exposure in the workplace(PDF, 647.66 KB)
- Last updated
- 27 October 2017