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SILICA IN THE WORKPLACE 8 365-AXJ-01-iGDO © 2020, Workplace Safety & Prevention Services (WSPS) 1 877 494 WSPS (9777) | 905 614 1400 | wsps.ca WSPS.CA How Can Exposure to Crystalline Free Silica be Controlled? Silicosis is a preventable occupational disease. Workplace exposure to crystalline free silica can be controlled by several possible means, which may be included in a control program. The control program is the product of the workplace assessment of exposure. Several possible strategies may be used depending on the effectiveness of existing facilities and practices. Usually a combination of controls is most suitable. A control program is necessary where the assessment shows that "a worker is likely to inhale silica and that the health of a worker may be affected." Note that in this context no reference is made to numerical values. The joint health and safety committee must also be consulted on the control program, which should include provisions for the following: A. ENGINEERING CONTROLS Engineering controls are most effective in workplaces in which the production of dust is presently uncontrolled. These often produce the most dramatic results when used properly and installed correctly. Engineering controls are selected to control emissions at their source. These may include any or all of the following: 1. Process Selection/Workplace Design Process selection and layout can significantly affect the production of silica-containing dusts. Attention to the mechanics of silica handling can lead to the selection of processes least likely to generate dust, and of workplace layouts which minimize the spread of dust. Where practicable, consider use of wet methods such as water sprays to reduce dust levels or use remote controlled tools at the impact site where a saw or grinder generates dust. These considerations are best addressed during the design stages. Mechanization often offers the advantage of increased production and improved protection of workers. 2. Equipment Selection The ideal time to address engineering controls is during the selection of new or replacement equipment. Equipment selected for silica handling or in which silica-containing dust is generated, should enclose the process and contain venting points capable of being connected to local exhaust ventilation. Use a combination of both water and ventilation controls, if possible. Use hand tools (e.g., drills, masonry saws, grinders) equipped with a shroud and a vacuum with a high efficiency particulate air (HEPA)-filter when wet methods are not practicable. Manufacturers' specifications should be examined to ensure that these capabilities are included. Performance specifications with expected warranty should be proposed by the purchaser and submitted as part of the purchasing requirement.

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