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Title: Size and concentration measurement of an industrial aerosol

Abstract

Several real-time particle sizing instruments were evaluated for measuring the size distribution and concentration of the aerosol produced during the high speed grinding of gray iron castings. Aerosol was sampled in the airstream entrained by the motion of a spinning grinding wheel in a pilot grinding operation. Measurement methods based on differing physical principles were selected for evaluation and compared: particle inertia (aerodynamic particle sizer and quartz crystal microbalance cascade impactor); light scattering (laser aerosol spectrometer); and projected-area microscopy (scanning electron microscope). Inferences of aerodynamic diameter based on measurements by the laser aerosol spectrometer consistently undersized that determined by the aerodynamic particle sizer by a factor of 1.5. Estimates of aerodynamic diameters from projected area diameters determined by scanning electron microscopy differed from those obtained by the aerodynamic particle sizer by a factor of 2. Differences appeared to be a non-linear function of particle diameter. Estimates of respirable mass determined from mass-weighted particle size spectra varied by a factor of 6 between the largest estimate (scanning electron microscope) and the smallest estimate (laser aerosol spectrometer).

Authors:
; ;
Publication Date:
Research Org.:
National Institute for Occupational Safety and Health, Cincinnati, OH
OSTI Identifier:
5011402
Resource Type:
Journal Article
Resource Relation:
Journal Name: Am. Ind. Hyg. Assoc. J.; (United States); Journal Volume: 7
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; AEROSOLS; PARTICLE SIZE; IRON; AIR; METAL INDUSTRY; SAMPLING; SCANNING ELECTRON MICROSCOPY; COLLOIDS; DISPERSIONS; ELECTRON MICROSCOPY; ELEMENTS; FLUIDS; GASES; INDUSTRY; METALS; MICROSCOPY; SIZE; SOLS; TRANSITION ELEMENTS; 500200* - Environment, Atmospheric- Chemicals Monitoring & Transport- (-1989)

Citation Formats

O'Brien, D., Baron, P., and Willeke, K.. Size and concentration measurement of an industrial aerosol. United States: N. p., 1986. Web. doi:10.1080/15298668691389928.
O'Brien, D., Baron, P., & Willeke, K.. Size and concentration measurement of an industrial aerosol. United States. doi:10.1080/15298668691389928.
O'Brien, D., Baron, P., and Willeke, K.. 1986. "Size and concentration measurement of an industrial aerosol". United States. doi:10.1080/15298668691389928.
@article{osti_5011402,
title = {Size and concentration measurement of an industrial aerosol},
author = {O'Brien, D. and Baron, P. and Willeke, K.},
abstractNote = {Several real-time particle sizing instruments were evaluated for measuring the size distribution and concentration of the aerosol produced during the high speed grinding of gray iron castings. Aerosol was sampled in the airstream entrained by the motion of a spinning grinding wheel in a pilot grinding operation. Measurement methods based on differing physical principles were selected for evaluation and compared: particle inertia (aerodynamic particle sizer and quartz crystal microbalance cascade impactor); light scattering (laser aerosol spectrometer); and projected-area microscopy (scanning electron microscope). Inferences of aerodynamic diameter based on measurements by the laser aerosol spectrometer consistently undersized that determined by the aerodynamic particle sizer by a factor of 1.5. Estimates of aerodynamic diameters from projected area diameters determined by scanning electron microscopy differed from those obtained by the aerodynamic particle sizer by a factor of 2. Differences appeared to be a non-linear function of particle diameter. Estimates of respirable mass determined from mass-weighted particle size spectra varied by a factor of 6 between the largest estimate (scanning electron microscope) and the smallest estimate (laser aerosol spectrometer).},
doi = {10.1080/15298668691389928},
journal = {Am. Ind. Hyg. Assoc. J.; (United States)},
number = ,
volume = 7,
place = {United States},
year = 1986,
month = 7
}
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