Tedlar bags have been evaluated as containers for gaseous benzene samples at source-level concentrations. Sample stability over time periods typically required in field work, “memory” effects, decontamination procedures, and the temperature range over which the bags can be success-fully used were subjects of this study. Benzene samples remained essentially unchanged for up to 17 days. Cooling to -40° C or heating to 70° C did not produce concentration changes. Above 105° C, decomposition of the bag seals was observed. No evidence of permeation loss at room temperature was observed, and absorptive loss could be observed only upon prolonged contact. Flushing the bags with nitrogen was sufficient to remove all traces of previous samples. Calibration mixtures were prepared in Tedlar bags by injecting measured quantities of liquid benzene while metering-in nitrogen gas. These bag standards were used to perform calibrations for the G.C. measurement of benzene-containing cylinders. Corroboration of these results by three other laboratories demonstrated that such bag samples are useful as calibration standards.
The Use of Tedlar Bags to Contain Gaseous Benzene Samples at Source-Level Concentrations
Scentroid Odour Regulation