出版社：National Institute of Occupational Safety and Health
摘要：A glass syringe with disposable membrane filters was tested as a constant-flow air sampling device. The principle of this sampling device is straightforward: when the syringe is inverted vertically, the syringe plunger falls at a constant speed if an appropriate flow restrictor is connected at the syringe inlet. In case of a 100ml syringe with two Teflon membrane filters of 0.50μm in pore size and 3mm in diameter, the flow rate was 3ml/min. The flow rate was constant for a 15-minute sampling period when two to eight filters were used as a flow restrictor. A sample volume of less than 50ml is sufficient for the determination of prganic solvent vapor at the ppm level, when gas chromatography with thermal desorption method is employed. Therefore, this sampling device is useful for determining the time-weighted average concentrations of organic solvent vapor in a working environment.
关键词：Constant-flow air sampler;Thermal desorption;Syringe;Organic solvent;Adsorption sampling
