Study On The Method For Rapid Determination Of Volatile Organic Compounds In Indoor Air

Volatile organic compounds (VOCs) are one of the main pollutants in indoor air. Total Volatile organic compounds (TVOCs) as the quatitive target of VOCs has been a monitoring item of indoor air pollutants in China. At present, the national standard method for determination of VOCs-thermal desorption / gas chromatography (GB/T18883-2002) required analyzing them at laboratory after sampling gas in situation and it is related to complicated manipulation, long time lag and high costs, as well as the results can not reflect the situation of indoor air pollutants real time. Furthermore, mostly sampling and analyzing instruments need to be imported, analytical method also referenced that from foreign countries, so it's development and application was confined in big degree. This situation has not adapted to requiring of indoor air quality detection.VOCs portable detector has many advantages, such as extensive measure range, high precision, good stability, speedy analysis, real time analysis etc., so it was widely used in recent years. However, there is a big difference in principle between national standard method and VOCs detector, moreover, this instrument is lack of canonical operation regulations and calibration measure, i.e. lack of authority and availability. The method of VOCs detection has not been ratified by related department in our country.The study on national standard method and speedy measurement for VOCs inindoor air was deeply progressed. The purpose of this paper was tried to discuss the shortage of national standard method and the possibility of speedy measurement to become standard method. VOCs reference materials and influence of analysis condition were also discussed in this paper, and make certain the comparable relation of tow method in certain condition. To PID detector, the concept of VOCs apparent concentration was set up to evaluate the relative pollution level of VOCs in indoor air.This paper confirmed 23 kinds of VOCs in indoor air as known VOCs, which is regulated by standard method(GB/Tl 883-2002), in this way ,the analysis process is predigested deeply, and it is more convenient to analyze much batch of sample. We select PGM-7240 VOCs detector(RAE. America) as experiment instrument ,which have good effect to detect single material and high precision RSD< 3% (n=8) .A lot of controlled experiments between standard method and speedy method were progressed in this paper. The results showed that two methods have relativity, ratio "R" focus on 1.5-3.5. It was found 10 kinds of VOCs, which have much proportion in indoor air, had similar "R" in theory, the average was 2.37.The outcome of the study provide the credible gist to improving and perfecting national standard method ,and to solving the standardization and transfer of quantity value for speedy detection method, and imposing a significance on promoting the research of VOCs in indoor air.