This article considers the role of individual return openings in controlling the spread of infection in a two-bed hospital ward. It proposes a simple and economical ventilation design capable of reducing cross-infection risk. A two-bed hospital ward ventilated by a ceiling-level low velocity diffuser was considered. Computational fluid dynamics analysis was used to simulate and compare particle removal efficiency of return openings. Different particle sizes were considered for simulating pathogenic contaminants and their concentration was calculated in patient breathing zones. A range of return opening velocities was tested. According to the results, boosting local individual return opening air velocity could effectively increase ventilation performance and particle removal efficiency could be significantly improved. The proposed personal exhaust opening system can be potentially applied in retrofitting practice in existing hospital wards with high cost effectiveness as compared to a full-scale renovation.
QC 20180406