摘要 目的：建立薄膜—电导率法总有机碳分析仪测量结果不确定度的评定方法。方法：分析了测量过程中不确定度的主要来源，即工作曲线的不确定度、测量仪器读数分辨率导致的不确定度、测量不重复性引起的不确定度、标准溶液引起的不确定度等，分别量化后合成标准不确定度，得到总有机碳测量的扩展不确定度。结果：通过对HTY-2500总有机碳分析仪在2000μg•L-1测量点测量结果不确定度的评定，其扩展不确定度为U95 = 49（μg•L-1）（k=2）。结论：本方法所建立的测量结果不确定度评定方法准确、可靠，可为薄膜-电导率法总有机碳分析仪的测量结果不确定度评定提供较为准确简便的方法。 关键词：总有机碳；测量不确定度；薄膜—电导率法 中图分类号：R917 文献标识码：A 文章编号：0254-1793（2008）12-0-0 Evaluation of Measurement Uncertainty for the Total Organic Carbon Analyzer with Membrane Conductmetric Detection Technology YAN Xiang-qing1，WU Xu-mei2 (1.Zhejiang Province Institute of Metrology, Hangzhou, 310013, China;2. Hangzhou Tailin Bioengineering Equipments Co. LTD, Hangzhou, 310052, China) Abstract: Purpose: The article set up an evaluation method of measurement uncertainty for the total organic carbon analyzer with membrane conductmetric detection technology. Method: The article analyzed the main resources of the uncertainty of the measurement, which include uncertainty of the working curve, uncertainty of the resolution ratio of the instrument, uncertainty of measure unrepeatability, uncertainty of standard solution, etc. It quantified these uncertainties respectively and composed them to a standard uncertainty. Finally it got the expanded uncertainty of the total organic carbon measurement. Result: It evaluated the measurement uncertainty of the total organic carbon analyzer at 2000μg•L-1 and got the expanded uncertainty which is U95 = 49（μg•L-1）（k=2）. Conclusion: The evaluation method of measurement uncertainty set up by the article is accurate, reliable, and it can offer comparatively exact and convenient method for measurement uncertainty evaluation of the total organic carbon analyzer with membrane conductmetric detection technology. Key words: total organic carbon; uncertainty of a measurement; membrane-conductometric detection technology