HVAC System Design in Healthcare Facilities and Control of Aerosol Contaminants: Issues, Tools, and Experiments
Ventilation design greatly affects disease transmission by aerosols in healthcare buildings and is necessary to protect patients and healthcare workers against Hospital Acquired Infections (HAI). The rising concerns for antibiotic resistance and the strong push to save energy are motivating an assessment of current situation and are supporting a multidisciplinary effort to use novel approaches and tools. The paper is suggesting a shift to performance-based concepts, made possible by a wider use of IAQ sensors and of CFD simulation tools. The paper highlights the key role of particles and Microbe-Carrying Particles, how they are generated and spread by people and can be controlled by dilution and filtration. The viable and non-viable particle measurement techniques are described and OPC emerge as a widely usable tool to quantitatively assess, monitor and control hospital ventilation. Being people the most relevant indoor particle source, it is shown how aerosol dispersion from people can be reduced using occlusive clothing and how different garments are performing in Test Chamber and in OT. The simulation and experimental study of a high-performance OT ventilation system is used in order to show potential benefits of OPC and CFD tools.
KeywordsHealthcare facilities Ventilation and air-cleaning Air cleaners and air filters Air sampling Indoor air quality
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