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1000
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Abstract/Summary
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This analytical method is a validated measurement procedure for the determination of chlorinated biphenyls (PCBs) in the gaseous state and bound to particles in workplace air for monitoring their MAK value at workplaces. Sampling is performed by drawing a defined volume of air through a quartz fibre filter located in the sampling head with an adsorption tube filled with Tenax TA connected downstream using a suitable pump. The flow rate is adjusted either to 0.5; 1.0 or 2.0 L per minute according to the used conical inlet listed in DIN EN 481. The collected PCBs are thermally desorbed and then analysed by means of gas chromatography‐mass spectrometry (GC‐MS). Quantitative evaluation is based on a 5‐point calibration using PCB 209 as internal standard. The limit of quantification (LOQ) is determined on the basis of ten standard solutions in the lower concentration range. The relative LOQ is 36 ng/m3, which is the sum of the collected PCBs on both the sorbent Tenax TA and the filter. The LOQ for the individual PCB congener per analysis sample is 0.17 to 0.56 ng (absolute). The expanded uncertainty for these parameters is between 15.4 and 16.4% for the individual PCB congeners.
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