The impact of ventilation systems on the risk of viral transmission (review article)

Understanding the aerosol transmission mechanism of respiratory infectious diseases is crucial for predicting indoor air circulation and optimizing ventilation system design. A literature search was conducted using various keyword combinations in the PubMed database. The selection included studies examining the impact of indoor microclimate parameters and ventilation system performance on the risk of viral transmission. Since 2020, there has been increasing interest in studying how viral infections spread via aerosols within buildings and transportation infrastructure, considering the operational conditions of engineering systems. Currently, substantial evidence supports the dependence of viral aerosol viability on indoor temperature and humidity levels. Maintaining an optimal relative humidity of 40–60% at standard room temperature is essential not only for aerosol stability but also for virus neutralization. However, there is a lack of studies investigating the effects of air mobility and indoor pollution on the stability of viral pathogens. A significant body of literature confirms the influence of ventilation system efficiency on infection risk in buildings. To reduce the spread of respiratory viruses, an air exchange rate of at least 30 m3/h per person is recommended. Based on the findings, a set of practical recommendations for ventilation system operation amidst increased disease incidence has been developed. Discrepancies between international and Russian regulatory requirements regarding indoor climate parameters and air quality standards have been identified, emphasizing the need for improved measures to mitigate the spread of respiratory infections.