Impact of Air Change Rates on Reducing Pathogen Transmission in a Healthcare Isolation Room

This study examines how different air change rates per hour or ACH influence contaminant spread from a patient within an isolation room at Universiti Teknologi Malaysia (UTM) in Johor Bahru, Malaysia. Understanding this relationship is crucial to safeguarding healthcare workers from direct contaminant exposure and controlling virus transmission in hospitals. The paper focuses on how ACH affects particle dispersion in an isolation setting. Field measurement on air temperature and velocity were collected and analyzed for validation. A CFD simulation was then conducted, accurately modeling the room environment to assess the impact of varying ACH levels, from 5 to 30, which encompasses the typical ventilation rates recommended in healthcare facilities. Our findings show notable changes in particle behavior and air quality at different ACH levels. Specifically, particle counts rose by 1.51% when increasing ACH from 5 to 10, decreased by 1.05% to ACH 15, then rose 1.76% to 663 particles at ACH 20, dropped 1.58% to ACH 25, and surged to 1666 particles at ACH 30. These results underscore how airflow and ACH interact, influencing particle spread and deposition. This study enhances our understanding of airflow in controlled healthcare environments, which is critical for infection control. Future research should consider adaptive ventilation strategies and temperature effects to further optimize isolation room conditions. The findings offer valuable insights for architects and policymakers working to improve the design and function of hospital isolation rooms.