Transmission characteristics of human exhaled particles and risk prediction methods of respiratory infectious diseases

Reviews the size distribution and transmission characteristics of human exhaled particles, and the risk prediction methods of airborne transmitted diseases in an enclosed space. The study finds that the number of small particles is more than that of large particles and the virus dose of small particles is more than that of large particles in human exhaled gases. The transmission characteristics of human exhaled particles are affected by air distribution and air change rates. The lock-up phenomenon of human exhaled particles may occur in displacement ventilation rooms, so it is not recommended in hospital wards. The natural ventilation and stack effect can cause pollutant transmission vertically in high-rise residential buildings. The inter-unit dispersion of infectious diseases in high-rise residential buildings can be reduced by improving the airtightness of building envelope and the ventilation rate of external windows. The results will provide guidance for the control of respiratory infectious diseases in terms of pollution sources, pollutant transmission process and personnel exposure.