Guides & Toolkits

Silica in the Workplace

This Stream includes all of our Guides & Toolkits Flipbooks.

Issue link: https://www.wsps.ca/resource-hub/i/1353610

Contents of this Issue

Navigation

Page 4 of 30

SILICA IN THE WORKPLACE 2 365-AXJ-01-iGDO © 2020, Workplace Safety & Prevention Services (WSPS) 1 877 494 WSPS (9777) | 905 614 1400 | wsps.ca WSPS.CA Silica: Its Occurrence, Uses and Health Effects What is Silica? Silica is the name of a group of minerals that contain silicon and oxygen in a chemical combination and have the general formula SiO 2 . Silica may be free, in which case only SiO 2 is present, or combined, in which the SiO 2 is combined chemically to some other atom or molecule. This difference is important to recognize, since the silica problem exists only with free silica. Labels on packages and product analysis sheets and Safety Data Sheets (SDS) must be read carefully for this reason. Free silica may occur as amorphous free silica, of which there are many forms, and crystalline silica, of which there are five principal forms. Certain materials contain both amorphous and crystalline silica. Silica-related diseases are associated only with crystalline silica. The most common examples of crystalline silica are beach or bank sands. A third form of free silica is fused silica, which is produced by heating either the amorphous or crystalline forms. Heating amorphous silica causes conversion to the crystalline form under appropriate conditions. The interrelationships between the crystalline and non-crystalline forms of silica are extremely important. Products containing amorphous silica are often heated to high temperatures during use in the workplace. A material initially containing no crystalline silica when installed may contain considerable quantities when removed. Figure 1 illustrates the interrelationship between the various forms of silica.

Articles in this issue

Links on this page

Archives of this issue

view archives of Guides & Toolkits - Silica in the Workplace