Behavior of cough droplets emitted from Covid-19 patient in hospital isolation room with different ventilation configurations

The world is now facing the Covid-19 pandemic and the control of Covid-19 spread in health care facilities is a serious concern. The ventilation system in hospital isolation rooms with infectious patients plays a significant role in minimizing the spread of viruses and the risk of infection in hospital. In this study, computational fluid dynamics (CFD) simulation is applied to investigate the important factors on transport and evaporation of multi-component cough droplets in the isolation room with different ventilation configurations. We analyzed the ef-fects of various air outlet positions on the removal efficiency of infectious droplets in isolation room and pro-posed the optimum location of exhaust vent in hospital isolation room to maximize the droplet removal efficiencies. We found that the evaporation rate of droplets is strongly dependent on the relative humidity (RH) and, at low RH, the large-sized droplets with Covid-19 virus can evaporate quickly and become small-sized aerosols to stay in air for a long time and the Covid-19 can propagate more easily through the respiratory or-gans during breathing. It also explains why the Covid-19 can propagate faster in winter with low humidity than in summer with high humidity.

Automated summary

This study investigates the transmission and evaporation of cough droplets in hospital isolation rooms using computational fluid dynamics (CFD) simulation. The effects of different ventilation configurations on droplet removal efficiency are analyzed, and the optimal exhaust vent location is proposed. The study finds that the evaporation rate of droplets is strongly influenced by relative humidity, with low humidity conditions facilitating easier transmission of Covid-19 through respiratory organs.