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With the spread of SARS-CoV-2 virus all over the world, the indoor air quality of commercial buildings has received intense attention. The evaluation of high-volume air purifiers (HAP, CADR≥800m3/h) is of unprecedented importance. According to the national standard GB/T 18801-2015, the purification performance of HAP and its three different replacement elements was tested by the environmental chamber method. The results show that the particulate matter purification of single effect filter is better than that of composite filter. The presence of particulate matter generated by activated carbon layer and bypass air flow leads to a difference of about 10% between the clean air delivery rate (CADR) value for the count and weight of composite filter. In the durability test, the CADR value decreases greatly when the smoke volume is 1000 pieces due to the increase of resistance and the electrostatic elimination effect of incense smoke. The CADR test standards of air purifiers in 5 countries were compared. Only Korea mentioned that when the air volume of the air purifier is greater than 960m3/h, 50m3 test chamber is used. However, due to the different sources of experimental dust and sampling methods, this standard does not conform to China's national conditions. The analysis results will provide reference for the formulation of relevant test methods and standards

The ongoing COVID-19 pandemic made us re-realize the importance of environmental disinfection in indoor areas. Several studies have documented that the air purification system combining UV light and high-efficiency particulate air (HEPA) filtration can successfully remove the virus from the air. However, UV light cannot penetrate deep into the HEPA, which causes the pathogens inside cannot be killed. In this study, we analyzed the potential of three-dimensional(3D) filter media combining with UV sterilization for the treatment of pathogen aerosols. Through geometric ray analysis, it is concluded that the transmittance attenuation of 3D filter material is linear, while that of ordinary fabric filter material is abrupt, which means UV light combining with common fabric filter can only kill the microorganisms on the surface. In order to prove that 3D filter with UV irradiation can eliminate microorganisms inside the 3D filter, we carried out an experimental verification. The results of the experiment shows that the bactericidal rate increased with UV dose and the k value is 3.75*10-4, much smaller than that in air UV disinfection. This indicates that although it is more difficult to kill pathogens on the surface of fibers than in air, 3D filter material with UV can kill the pathogens inside.