Effect of Ventilation on Indoor Airborne Microbial Pollution Control

Airborne microorganisms present a challenge to engineering control of indoor air quality (IAQ) in hospital, commercial, and residential buildings. This paper analyses the generation, transmission and control mechanism of airborne microbes, and presents one engineering control method that is ventilation commonly used in indoor air microbial contamination control. A mathematical calculous model of building ventilation system is developed to study on microbial contamination control. Discusses the relationship between different ventilation parameters and microbial concentration due to ventilation model, and gives the connection between ventilation rate and infection rate based on the Wells-Riley equation. Theoretical calculation results show that natural ventilation is ineffective if microbial pollution control is the main purpose of indoor air contamination control, mechanical ventilation should be taken. When indoor microbial pollution density is high, only ventilation cannot reduce the infection rate effectively, then other methods, such as air filtration, ultraviolet germicidal irradiation etc, should be combined for better control.