The impact of barrier arrangements on the transmission of respiratory infectious diseases in nursing homes in Hong Kong

Respiratory infectious diseases have affected the health of the elderly. This study investigated the optimization of physical barriers as a low-cost design strategy to reduce the risk of infection in nursing homes for the elderly in Hong Kong, which were significantly affected by the outbreak of COVID-19. First, data on two types of rooms, single and multi-occupancy, were collected from a field investigation of typical local nursing homes. Subsequently, Computational Fluid Dynamics (CFD) simulations were employed to analyse the effects of various barrier heights on the propagation, suspension, deposition and elimination of aerosol particles in these room types, thereby evaluating infection risks. The findings reveal that in single-occupancy rooms, a barrier height of 2.1 m is effective in curtailing the spread of the virus over distances. Conversely, in multi-occupancy rooms, while a 1.8-m barrier is necessary, the rate of particle suspension is considerably higher, necessitating additional ventilation measures. Based on these findings, the study provides quantitative criteria for the implementation of physical barriers as a low-cost physical measure in nursing homes and provides recommendations for the effective prevention of respiratory infectious diseases through design modifications.