工作场所空气中总粉尘浓度测定的误差分析  

Error Analysis for Determination of Total Dust Concentration in Air of Workplace

作　　者：崔凯 常继兵 周昕沁 

机构地区：[1]上海申丰地质新技术应用研究所有限公司理化检测实验室,上海201702

出　　处：《环境与职业医学》2016年第8期785-788,共4页Journal of Environmental and Occupational Medicine

摘　　要：[目的]测定工作场所空气中总粉尘的浓度，分析测定过程中各环节的误差来源。[方法]通过滤膜除静电、天平室温度、湿度调节和洁净室模拟采样，对工作场所空气中总粉尘浓度测定过程中，滤膜的准备、采样和样品的称量环节中可能存在的误差来源进行分析。[结果]以滤膜上总粉尘增量最低要求0．1mg计：滤膜未除静电（n=8，置于天平托盘正中）引起的称量误差为0．1mg的-50％～450％；采样后折叠的未除静电滤膜（n=10）在天平托盘上放置位置变化，引起的称量误差为0．1mg的110％～880％，而除静电后改变放置位置，则未引起称量结果的明显变化；采样气流（20L／min）导致滤膜（n=8）质量减少，引起的称量误差为0．1mg的-20％～0％；天平室温度和相对湿度在21．9-31．2℃和50．8％～66．1％范围内时，滤膜（n=8）的称量值变化引起的称量误差为0．1mg的-30％-40％。[结论]测尘滤膜所带静电是影响工作场所空气中总粉尘浓度测定准确性的主要因素。通过对滤膜除静电、调节采样前后天平室温度和湿度保持接近的质量控制措施，对聚丙烯粉尘工作岗位空气中总粉尘浓度的测定结果能够更为准确的反映劳动者接触工作场所空气中粉尘的浓度。[ Objective ] To measure total dust concentration in the air of workplace and analyze the sources of errors in determination. [ Methods ] Through eliminating static electricity of filter, changing temperature and humidity in balance room, and simulated sampling in clean room, we analyzed the potential error sources in determination of total dust concentration in workplace air, including membrane preparation, sampling, and weighing processes. [ Results ] Following the requirement for minimum total dust increment on filter of 0.1 mg, the error caused by static electricity of filter was -50%-450% （n=8）; that caused by position change on tray and having filter without static electricity eliminated and folded two times after sampling was 110%-880% （n=10）; that caused by filter weight loss due to sampling flow （20 L/min） was -20%-0% （n=8）; that caused by temperature （21.9-31.2 ℃） and relative humidity （50.8%-66.1%） change in balance room was -30%-40% （n=8）. However, no obvious change was observed in weighing results of filter with static electricity eliminated and position change on tray. [ Conclusion ] Static electricity of filter is a main factor that affects the accuracy of weighing of total dust concentration in workplace air. Through quality control measures such as eliminating static electricity of filter and keeping temperature and humidity in balance room consistent before and after sampling, more accurate dust concentration in polypropylene workplace air could be achieved.

关 键 词：工作场所 总粉尘 测尘滤膜 称量 误差 

分 类 号：R13[医药卫生—劳动卫生]