摘要
目的对能力验证2份化妆品样品菌落总数结果进行不确定度评定。方法化妆品菌落总数检测方法参照能力验证计划参试指导书和《化妆品卫生规范》(2007版)第四部分进行,按照《测量不确定度评定与表示》(JJF1059-2012)中的规定,分析不确定度的来源,采用A类评定极差法和B类评定对引入测量结果中的不确定度分量进行评定,计算本次能力验证测量结果的合成不确定度。结果样品稀释过程、样品加样量、重复性均会贡献测量结果不确定度,本次实验2个化妆品样品中菌落总数测量结果的相对合成标准不确定度(u_(crel))分别为0.066 9、0.067 1(以对数计),相对扩展不确定度(u_p)为0.134、0.134(以对数计),k=2。结论将样品的稀释过程、加样量和重复性检测等纳入不确定度评定过程,方法简单易行,可为之后相同类型的测量结果不确定度评定提供参考。
Objective To assess the uncertainty of total bacterial count in cosmetics by proficiency testing. Methods The total bacterial count was conducted under the direction of Hygiene Standard for Cosmetics（ 2007） and Reference Book for Microbiological Ability Verification Plan in Cosmetics. Then,analyze the sources of uncertainty and assess the uncertainty using range analysis based the Evaluation and Expression of Uncertainty in Mearsurement（ JJF1059-2012）. Finally,the synthesis method was used to calculate the uncertainty of this measurement. Results The dilution process,sample volume and the repeatability were the main causes of detection uncertainty. The relative synthetic standard uncertainty of the total number of colonies in the two cosmetic samples in this experiment（ ucrel） was 0. 0 669 and 0. 0 671 respectively（ in logarithms）,and the relative expanded uncertainty（ up）was 0. 134 and 0. 134（ in logarithms）,with k = 2. Conclusion This evaluation established an easy and reliable way to assess the uncertainty of total bacterial count considering the dilution series,sample volume and the repeatability. The sample dilution process,the amount of sample and repeatability detection were included in the assessment process of uncertainty,the method is simple and easy,which can provide reference for the measurement of uncertainty assessment.
出处
《中国卫生检验杂志》
CAS
2017年第24期3545-3547,共3页
Chinese Journal of Health Laboratory Technology
基金
国家卫生和计划生育委员会公益性行业专项课题(20-132004-1-2-1)
关键词
菌落总数
不确定度
能力验证
极差法
The total number of colonies
Uncertainty
Proficiency testing
Range analysis
