Record Display for the EPA National Library Catalog


Main Title Measurement of the Chemical Species That Contribute to Urban Haze.
Author Stevens, R. K. ; King, F. ; Bell, J. ; Highsmith, V. R. ; Whitfield, J. ;
CORP Author Environmental Protection Agency, Research Triangle Park, NC. Atmospheric Sciences Research Lab.
Year Published 1988
Report Number EPA/600/D-88/112;
Stock Number PB88-214697
Additional Subjects Urban areas ; Microanalysis ; Sulfur dioxide ; Haze ; Chemiluminescence ; Contaminants ; Particles ; Nitric acids ; Chemical analysis ; Ammonia ; Nitrous acid ; Aerosols ; Air pollution detection ; Air pollution sampling
Library Call Number Additional Info Location Last
NTIS  PB88-214697 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 15p
Measurements of the acidic (SO2, HNO3, and HNO2) and basic (eg NH3) gases that coexist with fine particles (<2.5 micrometes are often used in models to determine the sources of species that contribute to the so-called urban haze. The measurement of these trace gaseous and particle contaminants by instrumental methods is often limited by instrumental sensitivity and by the interferences of other contaminates that coexist with the species of interest. An example of this problem is the measurement of NO2 by chemiluminescence methods. This report describes a new denuder system and denuder coating arrangement that eliminates interferences between oxides of nitrogen species and improves the reliabilty and precision of measurements of HNO3 and HNO2. This paper will also describe the physical properties and sampling characteristics of an annular denuder system tailored for visibility studies and present results of measurements made to demonstrate precision and accuracy of data obtained with the annular denuder system.