TITLE Laboratory Validation of VOST and SemiVOST for Halogenated Hydrocarbons from the Clean Air Act Amendments List AUTHOR(S) J.T. Bursey, R.G. Merrill, R.A. McAllister & J.F. McGaughey PERFORMING ORGANIZATION NAME AND ADDRESS Radian Corporation P.O. Box 13000 Research Triangle Park, NC 27709 SPONSORING AGENCY NAME AND ADDRESS US Environmental Protection Agency Office of Research And Development Atmospheric Research and Exposure Assessment Laboratory Research Triangle Park, NC 27711 ABSTRACT The Clean Air Act Amendments of 1990, Title III, present a need for stationary source sampling and analytical methods for the list of 189 compounds. EPA has used Volatile Organic Sampling Train (VOST) and Semivolatile Organic Sampling Train (SemiVOST) sampling and analytical methods for this type of sampling of organic compounds in the past, but these methodologies have been completely validated for only a few of the organic compounds. In this study, the applicability of VOST and SemiVOST techniques to Clean Air Act halogenated compounds has been evaluated under laboratory conditions. The methods were evaluated first to determine whether the compounds could be analyzed successfully. For SemiVOST and VOST compounds, the analytes were analyzed by gas chromatography/mass spectrometry (GC/MS) techniques. Retention times for the analytes were determined, and reference mass spectra were generated so that primary and secondary quantitation ions could be selected. Recovery of the compounds from the sorbents was evaluated, and analytical detection limits were determined from spiked sorbents. Quadruple sampling trains were used to collect replicate samples for statistical evaluation of the dynamic spiking techniques for liquids (SemiVOST). This report presents the results of the laboratory experiments.