Terminally mounted exhaust filtration systems allow contaminants to be contained within the isolation room; the HEPA filters are installed within the room exhaust grille housings, most often at low level in the bed bay wall and at high level ceiling in the ensuite, according to an article on the Hospital and Healthcare website.
Because the ductwork is protected by the filter, there is a reduced risk of a potential contagion spreading in the ceiling service spaces.
With multiple rooms within the isolation room system, multiple terminal mounted HEPAs will be needed.
Because space within hospitals is at a premium, there is minimal space for pre-filters to protect the HEPA filter.
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