Control technology and exposure assessment for occupational exposure to crystalline silica: stone monument manufacturing - Hirons Memorial Works, Inc., Mount Orab, Ohio, report no. CT-247-22.
Kurimo-RW; Blade-LM; Heitbrink-WA
NIOSH 2003 Mar; :1-10
Worker exposure to crystalline silica was monitored during an abrasive blasting operation where stone monuments were being manufactured. A stencil was placed over the stone, and then abrasive blasting was used to produce the engravings by removing stone not covered by the stencil. The primary engineering control in use at this site was an exhausted enclosure with a face velocity of 160 fpm. Area and personal samples were collected during the survey to measure how much respirable silica was produced by this process. The geometric mean was 0.0071 mg/m3 in the breathing zone and 0.0026 mg/m3 for the area samples. The low concentrations appear to result from relatively effective engineering controls for the blasting operation, and, in addition, the blasting operation was performed only during part of the workday which resulted in less dust being generated. Further reductions in workers' exposures can be affected by enclosing the abrasive agent recycle chute, providing a vacuum for the worker to clean his clothing instead of using compressed air, and using a vacuum and/or wet wipe or water to remove dust from the completed monument and enclosure.
Silica-dusts; Stone-processing; Stone-products; Abrasive-blasting; Abrasives; Respirable-dust; Engineering-controls; Environmental-control-equipment; Control-technology; Region-5; Exposure-levels; Air-sampling; Breathing-zone
Field Studies; Control Technology
NTIS Accession No.
National Institute for Occupational Safety and Health