Dynamic generation of trace vapour standards of SVOCs using diffusion tubes

Generating trace vapour standard mixtures of SVOCs for calibration of analyses of gas phase samples of SVOCs for environmental monitoring and industrial hygiene is difficult. It is not really practical or possible using permeation tubes, which are often used for VOCs because the permeation rates are very small and many are oxygen-sensitive.

We shall illustrate how straightforward it is to achieve the dynamic generation of trace vapour standard mixtures of a wide range of SVOCs using the Tracer Cert® refillable diffusion tubes and the Tracer Cert® Superambient™ Thermostat System Super-AT470 at temperatures up to 470K. Nitrogen is used as carrier gas for oxygen-sensitive SVOCs, such as PAHs, and air is used as carrier gas for SVOCs not sensitive to oxygen, such as siloxanes and PCBs. Examples will be shown of applications for a varied range of SVOCs.