以无石棉纤维水泥板作为建筑涂料试验用板标准定值样品，对无石棉纤维水泥板测量不确定度的来源进行了分析。结果表明：影响无石棉纤维水泥板测量的不确定度因素主要有样品均匀性和各实验室定值结果的重复性。经F检验，样品均匀性良好；经t检验，样品长期稳定性至少为3 a（年）。采用8个实验室协作定值的方法对样品进行检测定值，同时对其进行了不确定度（k=2）评定，结果如下：表面平整度为（0.08±0.05） mm；表观密度为（1.54±0.01）×10³ kg ·m^-3；吸水率为（23.7±0.3）%。

The non-asbestos fiber (NAF) cement flat sheet was used as the standard value sample for the test of architectural coatings, and the source of measurement uncertainty of non-asbestos fiber cement flat sheet was analyzed. The results show that the main factors affecting the uncertainty in measurement of NAF cement flat sheet reference material included sample homogeneity and the repeatability of determined values at different laboratories. The results were validated by F-test statistical method and showed that the homogeneity of the samples was good. The results of long term stability validated by t-test statistical method was 3 years. A cooperative certification test was conducted by 8 laboratories. Meanwhile,the uncertainty (k=2) was evaluated as surface smoothness of (0.08±0.05) mm, apparent density of (1.54±0.01)×10³ kg ·m^-3 and the water absorption rate of (23.7±0.3)%.