Effect of ventilation type on the transport of coughed particles in a hospital room using computational fluid dynamics

Abstract

One of purposes in this study was to confirm the behavior of coughed particles under different ventilation conditions. Three types of ventilation systems were applied for this prediction, and the properties of coughed particles were calculated using computational fluid dynamics (CFD) in an intensive care unit. The changes of total airborne particles for each case showed different trends according to the ventilation type and time, but the deposited particles were similar in all conditions. Although the time taken for 50% of the particles to be deposited was the fastest in case 2 (ceiling mixing ventilation), the portion of deposited particles after 300s was only 5% in all conditions. In case 1 (centered exhaust ventilation), a relatively small number of particles were deposited on the wall, but the particle exhaust and deposition on the occupants were the highest. In case 3, the downward ventilation was applied as that recommended by the US Center for Disease Control and Prevention (CDC) and showed different exhaust efficiencies according to the particle size.