UVC-LED Irradiation Effectively Inactivates Aerosolized Viruses, Bacteria, and Fungi in a Chamber-Type Air Disinfection System.

In this study, the possibility of inactivating viral, bacterial, and fungal aerosols in a chamber- type air disinfection system by using an UVC-LED array was investigated and inactivation rate constants of each microorganism were calculated in fitting curves of surviving populations. UVC-LED array treatment effectively inactivated viral infectivity achieving 5 log reductions within 45 mJ/cm² for MS2, Qβ, and ΦX 174 viruses. UVC-LED array effectiveness in inactivating Escherichia coli O157:H7, Salmonella enterica serovar Typhimurium, Listeria monocytogenes, and Staphylococcus aureus aerosols achieved 2.5 to 4 log reductions within 1.5 to 4.6 mJ/cm². Also, 4 log reductions of Aspergillus flavus and Alternaria japonica were achieved at a dosage of 23 mJ/cm² using UVC-LED array irradiation. The highest UV susceptibility, represented by the inactivation rate constant, was calculated for bacteria followed by fungi and viruses. UVC-LED, an innovative technology can effectively inactivate microorganisms regardless of taxonomic classification and can sufficiently substitute for conventional mercury UV lamps. [ABSTRACT FROM AUTHOR]