空气中总挥发性有机化合物测定条件探讨

目的 探讨GB 50325-2001《民用建筑工程室内环境污染控制规范》中测定空气中总挥发性有机化合物(TVOC)浓度的最佳测试条件.方法 把含有苯、甲苯、乙苯、对、间二甲苯、苯乙烯、邻二甲苯7种不同化合物的钢瓶标准气注入到Tenax-TA采样管中,分别加热不同时间(15、30、60 s)和解析不同时间(15、30、45、60、90、120 s),分析测定结果的变化.结果 在Tenax-TA采样管在辅助器上的加热时间30 s,解析时间大于90 s的情况下,7种不同化合物的回收率均在90%以上,相对标准偏差均小于10%.结论 该方法提出了测定TVOC样品的最佳测试条件,其精密度和样品回收率均符合室内空气质量标准附录A《室内空气监测技术》中的要求.

Research on Optimal Test Condition for Determining TVOC in Air

Objective To research the optimal test condition for determining TVOC in air based on GB 50325-2001 Code for Indoor Environmental Pollution Control of Civil Building Engineering. Methods Seven kinds of standard gas (benzene, toluene, ethylbenzene, p-dimethylbenzene, m-dimethylbenzene, ethenylbenzene and o-dimethylbenzene) were injected into Tenax-TA sampling tube, then heated for different time and pyrolyzed for different time. Results Tenax-TA sampling tube was heated for 30 seconds and pyrolyzed for 90 seconds. The recovery rate of seven kinds of compounds was more than 90%. Relative standard deviation was less than 10%. Conclusion The optimal test condition for determining TVOC in air has been presented in this paper. The precision and sample recovery rate will meet the requirement of indoor air quality standard annex A Indoor Air Monitoring Technology.