Ventilation and Low-cost Strategies on Mitigating COVID-19 Infection Disease Transmission in Indoor Environment

During the normalization phase of COVID-19 epidemic, it is gradually reverted to use building space, especially for office. Prevention of airborne pollutant has emerged as a major challenge. Ventilation strategies can mitigate the spread of airborne disease in indoor environment, such as increasing ventilation rate, modifying ventilation mode, etc. The larger ventilation rate can lead to higher energy consumption may not effectively reduce infection risk. The potential of ventilation modes for COVID-19 control should be explored. Furthermore, it is necessary to adopt low-cost strategies, such as physical barrier, to increase the prevention efficiency while combining the ventilation system. This study was to investigate the impact of physical barrier on the spread of particles and infection risk in an office with a sufficient ventilation rate, and then compare different ventilation strategies, including mixing ventilation (MV), zone ventilation (ZV), stratum ventilation (SV) and displacement ventilation (DV), for the optimal one. The simulation model was mainly used in this work and validated by the experiment to show a good agreement with the model prediction. The results showed that (1) the SV showed greater performance in mitigating infection disease spread than MV, ZV and DV, with a minimum infection risk of 13%; (2) a barrier height of at least 60 cm above the desk surface is needed to effectively prevent the transmission of viruses with the risk of infection reduced by about 72%. This work can provide a reference for development of ventilation strategies as well as low-cost prevention interventions in public space oriented the prevention of COVID-19