In-depth study report: control technology for crystalline silica exposures in construction: exposures and preliminary control evaluation at a Restoration Preservation Masonry construction site, report no. CT-247-14.
NIOSH 2000 Nov; :1-21
Respirable silica exposures were measured while workers were using grinders to remove old mortar during a building renovation. Respirable silica exposures ranged from 0.1 to 4.5 mg/cum for workers who were grinding mortar. A ventilated shroud was used in an ineffective attempt to capture the dust generated by the grinders. The pressure drop through the shroud, hoses, PVC pipe, and settling chamber were thought to be too large in relationship to the fan's capability to develop static pressure at the needed flow rate. Furthermore, the air was discharged back into the workplace without passing through an appropriate filter to remove the respirable dust. The lack of a filter could result in the dispersal of respirable dust throughout the workplace.
Silica-dusts; Construction; Ventilation; Ventilation-equipment; Grinding-equipment; Region-1
Field Studies; Control Technology
NTIS Accession No.
National Institute for Occupational Safety and Health