Record Display for the EPA National Library Catalog


Main Title Precision and Accuracy of a Beta Gauge for Aerosol Mass Determinations.
Author Courtney, William J. ; Shaw, Robert W. ; Dzubay, Thomas G. ;
CORP Author Northrop Services, Inc., Research Triangle Park, NC.;Environmental Sciences Research Lab., Research Triangle Park, NC.
Year Published 1982
Report Number EPA/600/J-81-095;
Stock Number PB82-241969
Additional Subjects Aerosols ; Mass ; Air pollution ; Beta spectrometers ; Performance evaluation ; Gravimetric analysis ; Air filters ; Comparison ; Reprints ;
Library Call Number Additional Info Location Last
NTIS  PB82-241969 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 6p
Results of an experimental determination of the precision and accuracy of a beta ray attenuation method for measurement of aerosol mass are presented. The instrumental precision for a short term experiment was 25 micrograms for a 6.5 sq cm deposit collected on approximately 1 microgram/sq cm Teflon filters; for a longer term experiment the precision was 27 micrograms. The precision of the gravimetric determinations of aerosol deposits was 22 micrograms for Teflon filters weighted to micrograms. Filter re-orientation and air density changes that were able to adversely affect the beta ray attenuation results are discussed. Beta ray attenuation results are in good agreement with gravimetric measurements on the same filter-collected aerosols. Using dichotomous samplers in Durham, NC, aerosols were collected on Teflon filters in two size ranges. A regression line was calculated implicitly assuming errors in both measurements of mass. The 90% confidence intervals lay within 21 micrograms of the regression line for mean fine fraction aerosol mass loadings of 532 micrograms and within 15 micrograms of the regression line for mean coarse fraction aerosol mass loadings of 392 micrograms.