Respirable Concrete Dust – Silicosis Hazard in the Construction Industry

Details

• Personal Author:
  Linch KD
• Description:
  Concrete is an extremely important part of the infrastructure of modern life and must be replaced as it ages. Many of the methods of removing, repairing, or altering existing concrete structures have the potential for producing vast quantities of respirable dust. Since crystalline silica in the form of quartz is a major component of concrete, airborne respirable quartz dust may be produced during construction work involving the disturbance of concrete, thereby producing a silicosis hazard for exposed workers. Silicosis is a debilitating and sometimes fatal lung disease resulting from breathing microscopic particles of crystalline silica. Between 1992 and 1998, the National Institute for Occupational Safety and Health (NIOSH) made visits to construction projects where concrete was being mechanically disturbed in order to obtain data concerning respirable crystalline silica dust exposures. The construction activities studied included: abrasive blasting, concrete pavement sawing and drilling, and asphalt/concrete milling. Air samples of respirable dust were obtained using 10-mm nylon cyclone pre-separators, 37-mm polyvinyl chloride (PVC) filters, and constant-flow pumps calibrated at 1.7 L/min. In addition, high-volume respirable dust samples were obtained on 37-mm PVC filters using 1/2" metal cyclones (Sensidyne model 18) and constant-flow pumps calibrated at 9.0 L/min. Air sample analysis included total weight gain by gravimetric analysis according to NIOSH Analytical Method 600 and respirable crystalline silica (quartz and cristobalite) using x-ray diffraction, as per NIOSH Analytical Method 7500. For abrasive blasting of concrete structures, the respirable crystalline silica (quartz) concentration ranged up to 14.0 mg/m3 for a 96-minute sample resulting in an eight-hour time-weighted average (TWA) of 2.8 mg/m3. For drilling concrete highway pavement the respirable quartz concentrations ranged up to 4.4 mg/m3 for a 358-minute sample, resulting in an eight-hour TWA of 3.3 mg/m3. For concrete wall grinding during new building construction the respirable quartz measurements ranged up to 0.66 mg/m3 for a 191-minute sample, resulting in an eight-hour TWA of 0.26 mg/m3. The air sampling results for concrete sawing ranged up to 14.0 mg/m3 for a 350-minute sample resulting in an eight-hour TWA of 10.0 mg/m3. During the milling of asphalt from concrete highway pavement, the sampling indicated a respirable quartz concentration ranging up to 0.34 mg/m3 for a 504-minute sample, resulting in an eight-hour TWA of 0.36 mg/m3. The results of this work indicate the potential for respirable quartz concentrations involving disturbance of concrete to range up to 280 times the NIOSH Recommended Exposure Limit (REL) of 0.05 mg/m3 assuming exposure for an eight- to ten-hour workday. Considering the aging of the concrete infrastructure in the United States, these results pose a challenge to all who have an interest in preventing silica exposures and the associated disease silicosis. [Description provided by NIOSH]
• Subjects:
  Aerosols Air Pollution Air Pollution, Indoor Construction Industry Construction Materials Dust Hydrocarbons Irritants Lung Diseases Occupational Health Particulate Matter Quartz Respiratory Tract Diseases Safety Silicon Dioxide

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• Keywords:
  Air-quality Asphalt-concretes Author Keywords: Construction Concrete Abrasive Blasting Concrete Drilling Concrete Dust Concrete Grinding Concrete Milling Concretes Concrete Sawing Construction-materials Construction-workers Construction Dust Crystalline Silica Dust Exposure-limits Lung-disease Lung-disorders Particulate-dust Particulates Pulmonary-system-disorders Quartz-dust Respirable-dust Respiratory-irritants Respiratory-system-disorders Silica-dusts Silica Dust

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• ISSN:
  1047-322X
• Document Type:
  Text
• Genre:
  Journal Article
• Place as Subject:
  OSHA Region 3 ; West Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  DRDS - Division of Respiratory Disease Studies
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  209-221
• Volume:
  17
• Issue:
  3
• NIOSHTIC Number:
  nn:20022488
• Citation:
  Appl Occup Environ Hyg 2002 Mar; 17(3):209-221
• Contact Point Address:
  Kenneth D. Linch, Division of Respiratory Disease Studies, Surveillance Branch, National Institute for Occupational Safety and Health, Morgantown, West Virginia
• CAS Registry Number:
  Quartz (SiO2) (CAS RN 14808-60-7)
• Federal Fiscal Year:
  2002
• NORA Priority Area:
  Work Environment and Workforce: Special Populations
• 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:df49183e234977c572b48929cb2ce7bf6bdaeaa30a260225b1efdf5a4cb2e3435de4ea70457aad64ab5103892da5190f127672d8d06a140135064691a8b0706b
• Download URL:
  https://stacks.cdc.gov/view/cdc/199248/cdc_199248_DS1.pdf
• File Type:
  [PDF - 2.03 MB ]