Abstract: Based on the testing of mask particle filtration efficiency, this article discusses and analyzes the correlation between upstream and downstream photometers, the linear measurement ability and time characteristics of downstream photometers to ensure the accuracy of their measurement results, rather than just focusing on parameters such as flow rate, pressure, and mass concentration. The importance of correlation in ensuring the accuracy of filtering efficiency measurement results has been demonstrated through experimental data.The article introduces a linear range testing device for photometers, discusses the relevant judgment criteria based on measured data. Based on the particle mass loading experiment, the influence of time characteristics on the measurement results of filtration efficiency was analyzed. The article analyzes the objective requirement for photometers to meet a linear range spanning five orders of magnitude, and conducts linear experiments on the signal amplification circuit. This article introduces a linear range testing device and discusses the judgment criteria based on measured data. This article also conducted particle mass loading experiments and discussed the influence of time characteristics on the measurement results of filtration efficiency. Propose to use an improved in-situ aerosol diluter as a testing device for time characteristics. This device can provide stable and unified testing standards at a fixed filtration efficiency measurement point.