Design and validation of a wind tunnel for viral aerosol filtration testing

Face masks were heavily used during the SARS-CoV-2 pandemic to reduce the transmission of the virus by aerosols. These facial barriers are tested in laboratory against particles and bacteria, but their efficiency is not tested for viruses. This study presents a wind tunnel designed to evaluate the filtration efficiency of different material use in face masks against particulates, total viral genomes and assess filtration impact on viral infectivity. The test bench was validated theoretically by mathematical modeling and experimentally by testing the performance of standardized masks against particles and MS2 viruses (Emesvirus zinderi). Results demonstrate that the data obtained for particle filtration was reliable and that filtration efficiency against viruses can be measured with the device.