Study on the Prevention of the Spread of Airborne Pathogen with CFD Simulation and Experiments of Tracer Gas in Outpatient Departments of Medical Facility

추적가스실험과 CFD 해석을 통한 병원 내 외래구역의 공기감염균 확산 방지를 위한 연구

In KOREA, since the COVID-19 Pandemic, medical facilities have been strictly controlled for the purpose of controlling infectious diseases by revising the medical law. However, there is a need to examine the possibility of control and prevention of airborne infectious diseases at medical facilities actually operated. In this study, SF6 (Sulfur hexafluoride) tracer gas experiments were conducted to observe the spread of airborne infections in the outpatient area. SF6 gas concentration was measured under conditions of 100% outdoor air intake mode and air recirculation mode. SF6 gas concentration was not detected in the consultation room where the outdoor air inlet was 100%. However, when the air recirculation mode was activated, SF6 gas spread to the HVAC system and SF6 gas was detected in the feed diffuser and the consulting room. In addition, the design airflow in the outpatient area was very different from the airflow in actual operation. As a result of the CFD analysis, it is judged that the supply air volume is larger than the exhaust air volume. The results of the CFD analysis with increasing exhaust volume showed that it was able to prevent the outflow to the outside sufficiently. Therefore, it is necessary to adjust the exhaust amount so that the outpatient area is formed into a negative pressure so as not to be leaked to the outside. In addition, studies on the removing of pollutants controlled by negative pressure should be conducted. Consequently, to properly prevent the transmission of infectious diseases, it is necessary to control the air flow in the outpatient area and consider a suitable control methods including filter, UVGI, air cleaner etc.