Thermal desorption of SVOCs spiked on Tenax had response factors identical to on-column injection except for highly polar compounds like fatty acids. SVOCs spiked on quarts fiber filters had response factors that on an average were 80% of the on-column response factors (66% for oxygen containing compounds and 87% for non-oxygen compounds). Low nonogram on-tube amounts of SVOCs were found generally to have lower recoveries than larger amounts from both Tenax and quartz fiber filters. This appeared to be explained in part by a relative larger "memory" effect and lower desorption efficiency. In addition, it was indicated that the "memory" effect was an important source of background contamination's that might impair analysis of low nanogram on-tube amounts of some SVOCs. Polar SVOCs in the gas phase appear to adsorb to the quartz fiber filters. This functions as a precleaning of the sample and thus minimizes the problem with coeluting peaks. The relative standard deviations of air concentrations of 10 SVOCs in an office estimated from nine duplicate samples appeared to be sufficiently low to distinguish a day to day variation. 

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