Record Display for the EPA National Library Catalog


Main Title Evaluation of the PILLS IV /
Author Farthing, William E. ; Smith, Wallace B.
Other Authors
Author Title of a Work
Smith, Wallace B.,
CORP Author Southern Research Inst., Birmingham, AL.;Industrial Environmental Research Lab., Research Triangle Park, NC.
Publisher Environmental Protection Agency, Office of Research and Development, Office of Energy, Minerals, and Industry, Industrial Environmental Research Laboratory ; For sale by the National Technical Information Service,
Year Published 1978
Report Number EPA-600/7-78-130; SORI-EAS-78-611; EPA-68-02-2131
Stock Number PB-291 430
OCLC Number 04984592
ISBN pbk.
Subjects Particles--Measurement. ; Lasers. ; Light--Scattering.
Additional Subjects Particle size ; Gas detector ; Error analysis ; Light scattering ; Lasers ; Design criteria ; Performance evaluation ; Air pollution ; Laboratory equipment ; PILLS 4 instrumentation ; Air pollution detection ; Numerical solutions
Internet Access
Description Access URL
Library Call Number Additional Info Location Last
EJBD ARCHIVE EPA 600-7-78-130 Headquarters Library/Washington,DC 06/24/2013
EKBD  EPA-600/7-78-130 Research Triangle Park Library/RTP, NC 12/05/2003
ESAD  EPA 600-7-78-130 Region 10 Library/Seattle,WA 03/23/2010
NTIS  PB-291 430 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation vi, 46 p. : ill. ; 28 cm.
The report gives results of theoretical and experimental investigations of the operating characteristics of the PILLS IV (Particulate Instrumentation by Laser Light Scattering) in situ particle sizing instrument. Results of both investigations show large errors in sizing particles with the instrument. Attempts to correlate the experimental findings with qualitative theoretical explanations established a sensitivity to particle refractive index and detector response that seems to account for the observed characteristics. Further measurements would be required to test this explanation quantitatively. The prototype was designed to measure particle size using the ratio of intensities of light scattered from a particle at two small angles (14 and 7 degrees) with respect to an incident laser beam. The intensity ratio was chosen because of its relative independence of particle refractive index. However, the magnitude of the scattered intensity at 14 degrees is also used for several important decisions in the electronic processing logic which, for this particular optical system, render it especially sensitive to refractive index and detector variations for determinations of particle size distribution. Possible solutions to these problems were offered with only minor hardware changes.
Prepared for Environmental Protection Agency, Office of Research and Development. Contract no. 68-02-2131, T.D. 11007, program element no. EHE624. July 1978. Includes bibliographical references.