Respirable crystalline silica dust exposure during abrasive blast cleaning of bridge deck surfaces

Details

• Corporate Authors:
  National Institute for Occupational Safety and Health
• Description:
  The results of a study of respirable crystalline silica (14808607) dust exposures occurring during abrasive blast cleaning of bridge deck surfaces were discussed. Breathing zone samples were collected from seven abrasive blasters, six traffic controllers, nine hopper loaders, and three flaggers at two or three sites in North Carolina where bridge deck surfaces were being cleaned by abrasive blasting prior to being recoated. All blasters wore an air supplied respirator helmet. Use of respiratory protection by the other workers was less consistent. A hopper loader and traffic controller at one site wore disposable dust/mist respirators, whereas no workers except the blasters wore respiratory protection at another site. The breathing zone samples were analyzed for respirable dust and crystalline silica. The silica content of the respirable dusts at the worksites varied from 7.1 to 37.5%. Time weighted average (TWA) respirable silica exposures of the abrasive blasters at two sites varied from 0.02 to 0.20mg/m3. Exposure times varied from 91 to 168 minutes (min). No respirable silica was found in samples collected at the third site. TWA respirable silica exposures of the traffic controllers at the three sites varied from 0.05 to 0.53mg/m3 for exposure times of 79 to 299min. TWA respirable silica exposures of the hopper loaders varied from 0.04 to 0.35mg/m3 and the exposure times varied from 83 to 308min. The TWA respirable silica exposures of two flaggers at one of two worksites were both 0.02mg/m3. No silica was detected in the breathing zone of a flagger at the second site. The author concludes that all of the blast crews at the worksites had the potential for exposure to significant concentrations of respirable silica dust. Recommendations include having all employees including flaggers, even though they are usually located some distance from the actual blasting site, wear respiratory protection and performing real time monitoring of respirable silica dust exposures. [Description provided by NIOSH]
• Subjects:
  Construction Industry Dust Occupational Exposure Occupational Health Personal Protective Equipment Respiratory Protective Devices Safety Silicon Dioxide Workplace
• Keywords:
  Abrasive-blasting NIOSH-Author Occupational-exposure Respirable-dust Respiratory-protective-equipment Road-construction Silica-dusts Workplace-monitoring
• ISSN:
  1047-322X
• Document Type:
  Text
• Genre:
  Journal Article
• Place as Subject:
  North Carolina ; Ohio ; OSHA Region 4 ; OSHA Region 5
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  DSHEFS - Division of Surveillance, Hazard Evaluations, and Field Studies
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  81-83
• Volume:
  11
• Issue:
  2
• NIOSHTIC Number:
  nn:00233608
• Citation:
  Appl Occup Environ Hyg 1996 Feb; 11(2):81-83
• Contact Point Address:
  David Lipton, North Carolina Department of Environmental Health and Natural Resources, Occupational and Environmental Epidemiology Section, P.O. Box 27687, Raleigh, North Carolina 27611-7687
• CAS Registry Number:
  Quartz (SiO2) (CAS RN 14808-60-7)
• Editor(s):
  Tharr D
• Federal Fiscal Year:
  1996
• Peer Reviewed:
  True
• Source Full Name:
  Applied Occupational and Environmental Hygiene
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:b52b9068e2264e4a508f93560f509b8aacca02560603e6d8c39b5fd999b1c605528dd88578c1fd53b33e074361aff6b651fcf8d8749c5444d7143144462be7ac
• Download URL:
  https://stacks.cdc.gov/view/cdc/205498/cdc_205498_DS1.pdf
• File Type:
  [PDF - 531.74 KB ]