车间空气中氯乙烯的时间加权平均浓度测定

目的建立一种适合监测车间空气中氯乙烯时间加权平均浓度的方法。方法采用个体采样器、活性炭管进行个体采样,二硫化碳解吸30分钟,取解吸液1μl进行气相色谱测定,以保留时间定性,峰面积定量。结果本方法的线性范围为0·0264~1·6896mmol/L,相关系数为0·9999,最低检测限为1·2ng(进样量为1μl),该法重复性好,精密度试验不同浓度的相对标准偏差在3·8%~6·7%,平均解吸率为90·77%。结论该法各项指标均达到了“车间空气中有毒物质监测研究规范”的要求,可用于工作场所空气中氯乙烯的时间加权平均浓度测定。

Determination of time-weighted average concentration for vinyl chloride in the air of workplace

OBJECTIVE: To establish a gas chromatographic method with carbon disulfide desorption for time-weighted average (TWA) concentration of vinyl chloride in the air of workplace. METHODS: Vinyl chloride in the air was sampled individually with activated charcoal tube. Vinyl chloride was desorbed by carbon disulfide for 30 minutes and analyzed by GC (FID). Time was used for qualitative analysis and peak area was for quantitative analysis. RESULTS: Linearity range was 0.0264-1.6896 mmol/L and the coefficient of correlation was 0.9999. Limit of detection: 1.2 ng (injection of 1microl). Relative standard deviation that expressed precision ranged from 3.8% to 6.7% for different concentrations. And average desorption efficiency of carbon disulfide was 90.77%. CONCLUSION: These indicators were corresponding to the Chinese guideline of the method for determination of toxic substances in workplace air and confirmed to be suitable for determining TWA concentration of vinyl chloride in workplace.