口罩细菌过滤效率检测仪校准方法研究及不确定度分析

Research on the calibration method and uncertainty evaluation of mask bacterial filtration efficiency tester

口罩细菌过滤效率检测仪是评价口罩的细菌过滤效率参数所需的重要计量器具。该文依据安德森采样原理、微生物计数法、气体流量标准表法、电子分析天平直接称量法科学的设计对检测仪的阳性质控值,安德森采样管路采样流量、蠕动泵流量、喷雾流量示值误差整体计量特性参数的校准方法,分析得到各参数的数学物理模型,并对其不确定度进行分析,给出评定示例。结果显示阳性质控值的扩展不确定度为5.0×102CFU,喷雾流量示值误差扩展不确定度为1.3%,采样流量示值误差扩展不确定度为1.2%,蠕动泵流量示值误差扩展不确定度为0.7%。最后对检测仪科学的使用和标准的修制提供建议。

The mask bacterial filtration efficiency tester is an important measuring instrument for evaluating the bacterial filtration efficiency parameters of masks.This paper is based on Anderson sampling principle,direct counting method,gas flow standard meter method,and electronic Analytical balance direct weighing method.The calibration methods for the positive quality control value of the detector,the sampling flow indication error of Anderson sampling pipeline,the flow indication error of Peristaltic pump,and the flow indication error of spray are scientifically designed.After analysis we get the mathematical physics model of each parameter and give an evaluation example for uncertainty.The result shows that the expanded uncertainty of the positive quality control value is 5.0×102CFU,the expanded uncertainty of spray flow indication error is 1.3%,the expanded uncertainty of sampling flow indication error is 1.2%,and the expanded uncertainty of peristaltic pump flow indication error is 0.7%.At last,suggestions are provided for the scientific use and standard revision of detectors.