Evaluation of Dust Control Technologies in Construction Tasks

摘要

Significantly elevated exposures to silica dust have been widely documented in construction activities, especially concrete cutting and grinding. Although application of water streams or spays to the cutting surface can substantially control exposures, many construction situations make the use of water infeasible. In order to evaluate the effectiveness of local exhaust ventilation (LEV) as an alternative approach silica dust control in constructions, a series of three studies were done. The study proceeded by first testing the effectiveness of LEV controls on four different types of tools in an experimental setting, then characterizing exposures occurring in eight common masonry activities in the field, and finally, considering the effectiveness of LEV on surface grinders used in field conditions. In each study, measurements were made with and without the use of LEV, and personal respirable dust and silica exposures were measured during the activity. Measurements were obtained with an inline respirable dust cyclone and filter, and with a direct reading instrument (pDR) allowing for the quantification of peak levels, and adjustment of the data for task-specific time periods.