Source
American Industrial Hygiene Conference and Expo, May 21-26, 2005, Anaheim, California. Fairfax, VA: American Industrial Hygiene Association, 2005 May; :1
Abstract
Excessive exposures to crystalline silica can occur during the construction and renovation of roads and buildings. These exposures result from the disruption of surfaces or structures containing crystalline silica. Crystalline silica is a component of sand, concrete, brick, block, mortar, and some paints used to coat steel structures. Uncontrolled abrading, cutting, drilling and breaking of materials containing crystalline silica can result in exposures that exceed exposure limits for crystalline silica by as much as a factor of 100. Practical control measures provide significant exposure reductions. Effective control measures use water, high velocity low volume ventilation, or substitution of materials or processes. These control measures have different capabilities and limitations. Recent field trials have evaluated the capabilities and limitations of control measures, resulting in some surprises. For example, recent efforts to use alternatives to sand during abrasive blasting have not eliminated the potential for silica exposure because some steel structures are coated with paints that contain crystalline silica. However, water can effectively suppress dust generation in some situations, and local exhaust ventilation can reduce exposures."