Record Display for the EPA National Library Catalog


Main Title Automated Cryogenic Preconcentration and Gas Chromatographic Determination of Volatile Organic Compounds in Air.
Author McClenny, W. A. ; Pleil, J. D. ; Holdren, M. W. ; Smith, R. N. ;
CORP Author Environmental Monitoring Systems Lab., Research Triangle Park, NC. ;Northrop Services, Inc., Research Triangle Park, NC. ;Battelle Colubmus Labs., OH.
Year Published 1984
Report Number EPA/600/J-84/335;
Stock Number PB86-101763
Additional Subjects Gas analysis ; Monitors ; Air pollution ; Cryogenics ; Cold traps ; Gas chromatography ; Air pollution ; Trends ; Concentration(Composition) ; Performance evaluation ; Toluene ; Chloroform ; Exhaust emissions ; Automation ; Design criteria ; Sampling ; Reprints ; Volatile organic compounds ; Air pollution detection ; Ethylene/perchloro
Internet Access
Description Access URL
Library Call Number Additional Info Location Last
NTIS  PB86-101763 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 6p
The performances of two nominally identical automated monitors for quantifying volatile organic compounds were compared on identical ambient laboratory air samples. The monitors incorporate cryogenic preconcentration subunits specially designed for controlled release of liquid nitrogen to establish a -150 C trap temperature. Measured trends in concentration for perchloroethylene, toluene, and chloroform showed good agreement even at sub-ppbv levels during automated overnight runs, although some effects of adsorption were evident. In a second set of runs, concentration results for one system were plotted versus those for the other. The plots were linear and precise, but slightly biased, probably indicating a change in the system sensitivity between calibration and monitoring. Qualitative comparison using diluted automobile exhaust is also shown.