Silicon Carbide Whiskers: Characterization and Aerodynamic Behaviors

Details

• Personal Author:
  Cheng S ; Johnson NF ; Powell QH ; Smith SM
• Description:
  An analysis was undertaken of the physical and aerodynamic properties of silicon-carbide (409212) (SiC) whiskers to assess their potential as an occupational health hazard. Industrial grade SiC fibers (density 3.25+/-0.006 grams per cubic meter, surface area 1.4+/-0.1 square meters per gram) were dispersed into a stainless steel chamber at a flow rate of 22.5 liters per minute (l/min) using a small scale power disperser. Aerosol samples were collected through a mixed cellulose-acetate/cellulose-nitrate filter (25 millimeters, 0.3 micrometer pore, flow rate 2l/min) and a cascade impactor (flow rate 12l/min) to determine aerosol concentration. Electron microscopic analysis was performed to measure fiber dimension and morphology. Particle sizes were determined after samples were separated via a Lovelace aerosol particle separator. SiC particle sizes ranged from 0.65 to 1.9 micrometers. The majority of SiC whiskers were straight and rod shaped, although single bends (12%) and double bends (2.7%) were also observed. A log normal distribution of SiC whisker length and width was noted. Fiber axis orientation was shown to influence fiber aerosol aerodynamic size. Aerodynamic size distribution estimates from data collected using the cascade impactor were smaller than those from data collected with the aerosol centrifuge. [Description provided by NIOSH]
• Subjects:
  Aerosols Dust Occupational Exposure Occupational Health Particulate Matter Respiratory Protective Devices Safety Silicon Compounds
• Keywords:
  Aerosol-sampling Dust-analysis Fibrous-dusts NIOSH-Grant NIOSH-Publication Occupational-hazards Particle-aerodynamics Respirators Silicon-compounds
• ISSN:
  0002-8894
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  New Mexico ; OSHA Region 6
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  56
• Issue:
  10
• NIOSHTIC Number:
  nn:00238997
• Citation:
  Am Ind Hyg Assoc J 1995 Oct; 56(10):970-978
• Contact Point Address:
  Aerosol Science Lovelace Biomed & Environ Res PO Box 5890 Albuquerque, NM I 87185
• CAS Registry Number:
  Silicon monocarbide (CAS RN 409-21-2)
• Federal Fiscal Year:
  1996
• NORA Priority Area:
  Respirator Research
• Performing Organization:
  Lovelace Institutes, Albuquerque, New Mexico
• Peer Reviewed:
  True
• Start Date:
  19911201
• Source Full Name:
  American Industrial Hygiene Association Journal
• End Date:
  19950929
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:0b414a0ff1304bf74ce050740c7dd8473c0429e26cba47c967cd313de0e00933ce81f297507f2178641f45276bb2bb26039b436db6d16f0ba77e1e96f56f6399
• Download URL:
  https://stacks.cdc.gov/view/cdc/197955/cdc_197955_DS1.pdf
• File Type:
  [PDF - 1.06 MB ]