Collection of silica and asbestos aerosols by respirators at steady and cyclic flow

Details

• Personal Author:
  Brosseau LM ; Ellenbecker, Michael J. ; Evans JS
• Description:
  The performance of electrostatically charged dust/mist respirator filters when challenged with silica (7631869) and asbestos (1332214) were studied under conditions similar to those used for NIOSH approval tests (continuous flow of 0.032 cubic meters/minute) and under conditions of cyclic flow. The filters were obtained from three different manufacturers. Under continuous flow conditions, the mass penetration of silica averaged 0.1% or less for filters from all three manufacturers. Mass penetration of silica at cyclic flow averaged 0.2% for manufacturer 1, 0.4% for manufacturer 2, and 1.1% for manufacturer 3. With asbestos, penetration under continuous flow conditions was almost always less than 0.5%. Under cyclic flow conditions, penetration of asbestos was less than 0.1% for filters from manufactures 1 and 2 and about 0.6% for manufacturer 3. The results suggest that respirator tests using silica aerosols may not be indicative of the performance that will be experienced when respirators are challenged with asbestos aerosols. Further, the study indicates that greater aerosol penetration occurs under conditions of cyclic flow than under steady flow. Finally, it appears that the stress on exhalation valves under cyclic flow may be sufficient to induce valve failure and thereby dramatically increase aerosol penetration into the respirator. In light of these findings the authors suggest that the NIOSH testing methods which rely on assessment of mass penetration of silica aerosols under steady flow conditions should be reconsidered. In addition they suggest that methods for evaluating the life cycle performance of respiratory components such as valves should be developed. [Description provided by NIOSH]
• Subjects:
  Asbestos Inorganic Chemicals Occupational Health Personal Protective Equipment Respiratory Protective Devices Safety Silicon Dioxide Staff Development
• Keywords:
  Asbestos-fibers Equipment-reliability NIOSH-Grant NIOSH-Publication Personal-protective-equipment Respirators Respiratory-protective-equipment Silica-dusts Training
• ISSN:
  0002-8894
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  Massachusetts ; OSHA Region 1
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  420-426
• Volume:
  51
• Issue:
  8
• NIOSHTIC Number:
  nn:00196543
• Citation:
  Am Ind Hyg Assoc J 1990 Aug; 51(8):420-426
• Contact Point Address:
  Physiology Department, Harvard School of Public Health, 665 Huntington Avenue, Boston, MA 02115
• CAS Registry Number:
  Asbestos (CAS RN 1332-21-4) ; Silica (CAS RN 7631-86-9)
• Federal Fiscal Year:
  1990
• Performing Organization:
  Harvard University, Boston, Massachusetts
• Peer Reviewed:
  True
• Start Date:
  19770930
• Source Full Name:
  American Industrial Hygiene Association Journal
• End Date:
  19940630
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:5cbc7d341b1341b1a667ca1d3063a2d15047dfbb6a7be1e3f1b8f9267aa8d4764dcc6ac98aa9df4047d41fe2a8a5a5c2ea064b7f6c02ec004be87be3b216ba88
• Download URL:
  https://stacks.cdc.gov/view/cdc/204355/cdc_204355_DS1.pdf
• File Type:
  [PDF - 786.96 KB ]