The use of automated gas chromatographs at air quality network monitoring stations to obtain measurements of ambient concentrations of volatile organic compounds (VOCs) has been a goal of EPA's Atmospheric Research and Exposure Assessment Laboratory. Presently, instrument designs require excessive amounts of cryogen to preconcentrate and resolve the more volatile organic compounds. The large consumption of cryogen becomes a major disadvantage when deploying the automated systems in field monitoring studies. In the current work a closed cycle cooling device was evaluated for its capability in replacing or reducing the need of cryogen for operating automated gas chromatographs.

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