A Virus Aerosol Chamber Study: The Impact of UVA, UVC, and H₂O₂ on Airborne Viral Transmission

The COVID-19 pandemic highlighted the urgent need to control airborne virus transmission, particularly in indoor environments with limited ventilation. This study evaluates the effectiveness of UVA and UVC irradiation, along with hydrogen peroxide (H₂O₂), in inactivating aerosolized viruses. A 19 m³ virus aerosol simulation chamber, replicating indoor conditions, was used to simulate human respiratory emissions by aerosolizing <i>Escherichia</i> phage T4 (T4 phages) embedded in a pig mucin medium that mimics respiratory aerosols. Results showed a clear, dose-dependent reduction in viral genome copies with UVC exposure, where a dose of 129.9 mJ/cm² reduced over 99% of the viral genome copies. Although less efficient, UVA still contributed to virus inactivation, reducing detectable phages to 20% at 513.30 J/cm². Mucin provided a protective effect, making virus removal more challenging. Hydrogen peroxide enhanced disinfection, with 1.6 ppm reducing viral genome copies by 78%, and higher concentrations (up to 16 ppm) achieving over 99% reduction in the dark condition. The combination of UVA/UVC with H₂O₂ further enhanced disinfection, eliminating detectable virus genome copies entirely. These findings underscore the potential for using combined UV light and chemical treatments to effectively mitigate airborne viral transmission in enclosed spaces.