Ventilation of general hospital wards for mitigating infection risks of three kinds of viruses including Middle East respiratory syndrome coronavirus

Abstract

This study investigates the effectiveness of ventilation design strategies for general hospital wards in terms of virus removal capacity. A typical semi-enclosed six-bed general ward of Hong Kong hospitals and three respiratory viruses, namely Middle East respiratory syndrome coronavirus (MERS-CoV), severe acute respiratory syndrome coronavirus (SARS-CoV) and H1N1 influenza virus, were chosen for the computational fluid dynamics (CFD) simulation of airflow field and virus dispersion inside the ward. The results demonstrated that the location of an infected patient would affect the infection risks to other occupants and healthcare workers inside the same hospital ward, and an increased air change rate in the ward could reduce the risk of infection from direct contact and inhalation. It was found that an air change rate of 9 h À1 could effectively minimize the deposition and floating time of respiratory virus particles while maximizing energy efficiency. This study should provide a useful source of reference for the hospital management to mitigate the risk of infection with MERS or other airborne transmitted viruses through better ventilation design strategies.

A numerical study of ventilation strategies for infection risk mitigation in general inpatient wards

“…3(b) depicts that the overall airflow pattern in the cubicle is directed towards the ward corridor. These results are consistent with those presented in our previous case study (Yu et al 2017). Due to the existence of obstructions such as patients and beds, several eddies can be seen within the ward cubicle.…”

“…A typical semi enclosed six bedded general inpatient ward cubicle with dimensions 7.5 m (L) × 6 m (W) × 2.7 m (H) and a between-bed spacing of 1 m as illustrated in Fig. 1 was used in this study (Li et al 2005;Yu et al 2017). The cubicle was mechanically ventilated (with a positive pressure towards the corridor) and accommodated six supine patients.…”

Effects of indoor environmental parameters related to building heating, ventilation, and air conditioning systems on patients' medical outcomes: A review of scientific research on hospital buildings

“…A study on 4‐bed patient rooms showed a minor reduction in infectious disease transmission through hand colonization when ventilation rates change from four ACH to six ACH . The results of a CFD simulation in the general wards of Hong Kong hospitals showed that a flow rate of nine ACH effectively minimized infection risk of three respiratory viruses . Table below summarizes the recommended minimum total ACH of the supply air and outside air comparison between Ninomura and Bartley and English…”

A Physicist View of COVID-19 Airborne Infection through Convective Airflow in Indoor Spaces

“…The airflow pattern should be studied for all such facilities to avoid the spread of infection to large distances from a single infected person. The safest rooms must be those equipped with the air sucking ventilator at the top, like hospital surgery rooms [24].…”