Personalized Ventilation: Personalized Exhaust Ventilation Strategy for Reducing the Risk of Airborne Cross Infection in Healthcare Centre Consultation Rooms

Several severe acute respiratory syndrome outbreaks in the last 15 years have highlighted the issue of short range aerosol transmission between healthcare workers and the patients. Concerns about the ventilation system design in healthcare centres have become topical and important. To minimize the spread of contaminated air exhaled by patients within the shortest possible time, personalized ventilation - personalized exhaust (PE) system has been developed in this study. A typical consultation room which is ventilated by either mixing ventilation or displacement ventilation is designed in the experiment with an infected person (IP) seated 0.6 m away facing the seated healthy person (HP). Tracer gases N₂O were used to simulate the contaminated exhaled air from an infected person. While previous studies focus on the exposure amount and reduction of the infected person, this study, adopts the Evacuation Efficiency (ratio of tracer gas concentration at exhaust without PV-PE to the tracer gas concentration at the breathing zone of HP with or without the PV-PE) at the breathing zone of the healthy person as the evaluation index, focus on the evaluation of PV-PE performance.