A Study on the Current Status of Ventilation Systems in Infection-Vulnerable Facilities and the Assessment of Airborne Transmission Risk of Respiratory Infectious Diseases

Abstract

This study quantitatively assessed the airborne transmission risk of respiratory infectious diseases in infection-vulnerable facilities, focusing on the current status of their ventilation systems. Field investigations were conducted at 32 facilities across Korea, including long-term care centers, mental health care facilities, and rehabilitation facilities. Only 56.3% of these facilities had mechanical ventilation systems in at least a portion of their buildings. Using the K-VENT tool, which is based on the Wells–Riley equation, 74 representative spaces were analyzed. This analysis considered natural ventilation, mechanical ventilation, and infiltration under actual operating conditions. The findings revealed that airborne transmission risk varied depending on space usage, occupancy density, activity level, and effective ventilation rate. Collective activity spaces, such as program rooms, auditoriums, and therapy rooms, consistently showed high risk, even when ventilated. While natural ventilation resulted in lower average risk in some residential rooms, it also exhibited significant variability. In contrast, mechanical ventilation offered relatively stable, though not always sufficient, risk reduction.