Monitoring VOCs in air using sorbent tubes followed by thermal desorption capillary GC analysis: Summary of data and practical guidelines

This paper presents a review of current practice and recent research into the use of sorbent tubes for monitoring VOCs in ambient air. Data are presented that demonstrate the viability of sorbent tubes with regard to artifact formation, analyte range, storage stability, concentration range, and recovery; the implications of this data are discussed in terms of detection limits, method validity, and method limitations. Guidance is also presented on the practical application of sorbent tube sampling derived from this information-for example, sorbent selection, pump flow rates, safe sample volumes, storage conditions, etc. Techniques and practical considerations for the thermal desorption-capillary GC analysis of sorbent tubes-such as calibration methods, moisture management, method validation procedures, and typical analytical conditions-are also reviewed and discussed. Expected analytical performance is presented in terms of precision and detection limits.