Airflow distribution in hospital isolation rooms with different ventilation and exhaust vent configurations

Abstract

Negative pressure isolation rooms can accommodate and treat patients with highly infectious diseases (such as COVID-19). Airtight conditions in the isolation room protect against infectious diseases. To control airflow and minimize infection risk within the isolation room, this study proposes three exhaust outlet vents with three air change per hour (ACH) conditions, 12, 24 and 48 ACH, in a single-bed hospital room using a computational fluid dynamics (CFD) approach. Results show that using the same ACH air velocity is relatively unaffected by the type and location of the exhaust air vent. The current case, case 1 and case 2 had average velocities of 0.121, 0.130 and 0.116, respectively. When the ACH was increased to 48, the average velocity was decreased to 0.663 m/s in case 1 and 0.589 m/s in case 2, compared to 0.711 m/s in the current case. In terms of infection probability, the study found that in the scenario of 12 ACH, the infection probability for case 1 and case 2 was increased by 11.85% and 3.96%, respectively, compared to the current case. The exhaust air vent in case 2 could effectively prevent the spread of pollutants when it was set to 48 air changes per hour and had the lowest risk level at 10.11%.