The efficacy, effectiveness and safety of SARS-CoV-2 disinfection methods (including ozone machines) in educational settings for children and young people

While evidence for the importance of transmission of SARS-CoV-2 from contaminated surfaces is limited, ozone disinfection methods have been considered for surface cleaning as a response to stopping the spread of the virus in educational settings. This rapid evidence summary aimed to search the available literature and summarise findings on the surface survival of SARS-CoV-2, efficacy and effectiveness of ozone machines against SARS-CoV-2, and benefits and harms caused by using these cleaning technologies, including their impact on health. Alternative cleaning technologies, such as light-based technologies and hydrogen peroxide vapour, were also investigated. Findings indicate that gaseous ozone can inactivate different bacteria and viruses, although there is a lack of direct evidence investigating the effect of these cleaning methods on SARS-CoV-2 in real-world settings, specifically in schools. However, regarding harm, ozone is a highly reactive oxidising agent, and high concentrations can contribute to decay of building materials, and health issues (mainly respiratory) by direct exposure or by-product formation. Therefore, leading environmental health organisations do not recommend the use of ozone cleaning technologies in real-world settings, such as schools. Research and policy focus may need to shift towards other interventions that could help reduce transmission, and consequently minimise disruption to education.