Journal of The Korea Institute of Healthcare Architecture (의료ㆍ복지 건축 : 한국의료복지건축학회 논문집)

Korea Institute of Healthcare Architecture (한국의료복지건축학회)
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A Numerical Study on Coughed Particle Dispersion and Deposition in Negative Pressure Isolation Room according to Particle Size

음압격리병실에서의 기침 토출입자의 입경에 따른 확산 및 침적에 대한 수치해석 연구

  • Jung, Minji (Graduate School, Department of HVAC & Firefighting Engineering, Gachon University) ;
  • Hong, Jin Kwan (Department of HVAC & Firefighting Engineering, Gachon University)
  • Received : 2018.04.13
  • Accepted : 2018.05.08
  • Published : 2018.06.15
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Abstract

Purpose: This study investigates the influences of coughing direction and healthcare worker's location on the transport characteristics of coughed particles in airborne infection isolation room (AIIR), which is commonly called negative pressure isolation room, with a downward ventilation system. Methods: Computational Fluid Dynamics (CFD) was used to simulate the airflow and for tracing the behavior of particles. Results: The results show that the airflow pattern and coughing direction have a significant influence on the characteristics of particle dispersion and deposition. When healthcare workers are in the isolation room with the patient who is lying on the bed, it is recommended to be located far from the anteroom to reduce the exposures from infectious particles. And when the patient is lying, it is more effective in removing particles than when the patient is in Fowler's position. Although it is an isolation room that produces unidirectional flow, coughing particles can spread to the whole room and a large number of particles can be deposited onto patient, bed, side rails, healthcare worker, ceiling, floor, and sidewall. Implications: Following the patients' discharge or transfer, terminal cleaning of the vacated room, furniture, and all clinical equipment is essential. Also, it is necessary to establish detailed standard operating procedure (SOP) in order to reduce the risk of cross-contamination.

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