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In recent years , with the rapid spread of Chemical Industry, industrial solvent has been used in large amounts. The air in workplace is full of aromatic hydrocarbon, which emit from solvent. In 2007, china has issued the National Standards“occupation exposure limits for hazardous agents in the workplace 2.1-2007 GBZ”, this standard has strict restrictions on aromatic hydrocarbon. In the same year, the health department issued the“methods for determination in the air of workplace 160-2004 GBZ/T”, it provides a method of determination of aromatic hydrocarbon in workplace. The targets of this method is benzene, toluene, xylene (three isomeric), styrene. It sampling on carbon tube, solvent desorbed or indirect thermal desorption and acked column gas chromatography to determination of aromatic hydrocarbon. But this method is serious influenced by air moisture, the detect limits of this method are higher, the average desorption efficiencies are lower.This paper supplied a method of determination of aromatic hydrocarbon in workplace by thermal desorption and GC in tenax-TA adsorbent. This method solves the defects in the current version of the national standards. Sampling and analysis conditions have been experimented, such as sampling flowrate, sampling volumes, storage of loaded samples, desorption time, desorption temperature, temperature programme, the operation of the method were optimizedThe performances of aromatic hydrocarbon are as follows: linear correlation coefficient of all standard curves are greater than 0.999, and the relative standard deviations are 2.1%～6.6%, accord with the precision required, the average desorption efficiencies are over 80%, and most achieved 90%, the detect limits of the method are lower, lower than 1.81×0-4mg/m3, accord with the standard required. Organic compounds are laid in tenax-TA tube for five days, the loss rates lower than 5%, so it can be kept five days after sampling. Compared with sampling on carbon tube acked column gas chromatography method of the National Occupational Health Standards“methods for determination in the air of workplace 160-2004 GBZ/T”, the operation of this method is simpler. It could avoid the environment pollution using volumes high pure CS2. The detect limits of the method are lower, the average desorption efficiencies are higher, the metering range are wider, all of these performances are better than the current version of the national standards.
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