Peak Exposures in Aluminium Potrooms: Instrument Development and Field Calibration

Details

• Personal Author:
  Carter SR ; Seixas, Noah S. ; Thompson ML ; Yost MG
• Description:
  Aluminium smelter potrooms are unique in that workplace exposures to hydrogen fluoride (HF), sulfur dioxide (SO2), and particulate matter occur simultaneously for some tasks. The peak exposures to these contaminants are of increasing interest in discovering the etiology of respiratory health effects. While a variety of direct-reading instruments are available for sulfur dioxide and particulate matter, only a few exist for hydrogen fluoride. The sensors in these HF instruments have a cross-sensitivity to sulfur dioxide making it difficult to monitor HF in an environment that also contains SO2. To overcome this problem, we assessed the simultaneous use of two electrochemical instruments: one with a SO2 sensor that does not respond to HF and the second with a hydrogen fluoride sensor that responds to both HF and SO2 in a 1 : 1 ratio, termed 'total acid gas'. The difference in the response between the two instruments should indicate the HF concentration: [HF + SO2] minus SO2 equals HF. The performance characteristics of this sampling train were evaluated in the laboratory through the generation of both HF and SO2 with permeation tubes. The response and recovery times for the SO2 only instrument were acceptable (6 and 15 s, respectively), but the "total acid gas" instrument exhibited both slow response and slow recovery approaching three and six min. The association between the traditional integrated filter sampling method and the direct-reading instrument for SO2 is 0.80 (Spearman's rho). The use of the digital filter strengthens the association between the HF direct-reading instrument and the integrated samples from 0.41 to 0.68. [Description provided by NIOSH]
• Subjects:
  Acids Fluorides Occupational Health Safety
• Keywords:
  Acid-gases Fluoride-compounds Gas-indicators Gas-meters Gas-sampling Hydrogen-ion-activity Sampling Sampling-equipment Sampling-methods
• ISSN:
  1464-0325
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  OSHA Region 10 ; Washington
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  6
• Issue:
  11
• NIOSHTIC Number:
  nn:20029011
• Citation:
  J Environ Monit 2004 Nov; 6(11):932-937
• Contact Point Address:
  Department of Occupational and Environmental Health Sciences, University of Washington, P.O. Box 357234, Seattle, WA 98195, USA
• Email:
  srcarter@u.washington.edu
• CAS Registry Number:
  Hydrofluoric acid (CAS RN 7664-39-3) ; Sulfur dioxide (CAS RN 7446-09-5)
• Federal Fiscal Year:
  2005
• Peer Reviewed:
  True
• Source Full Name:
  Journal of Environmental Monitoring
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:dfa337ee0337aaefb51a77ce9a7262e5659a7be90e203a9c49681ea7e6ebe09a8e47823f14362f8d83a63a519a4de956ff9b8debc4ec21bd73a9b3eb5bd69f9b
• Download URL:
  https://stacks.cdc.gov/view/cdc/190088/cdc_190088_DS1.pdf
• File Type:
  [PDF - 656.25 KB ]