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Endoscopy Unit Implementation of a Sealed In-Room Air Purifier with Ultraviolet Irradiation Reduces Bacterial and
Monique T Barakat1, Linda D Lee2, Natalie Conti3
1Division of Gastroenterology and Hepatology, Stanford University School of Medicine, Stanford, CA, 94305, USA.
Purpose:
There is a need for enhanced air quality in healthcare settings, particularly in areas with high levels of airborne particles and complex room layouts. This study evaluated the impact of germicidal ultraviolet air purification devices (GUVAPD) on bacterial contamination and airborne particle levels in endoscopic procedural rooms.
Methods:
We compared two endoscopy rooms and assessed whether GUVAPDs would further improve air quality above standard cleaning protocols. We compared an experimental room equipped with four germicidal ultraviolet chambers (Clean Air Unit, UV Angel) and a control room; both rooms performed similar endoscopic procedures. Microbial air and settled surface samples were collected, and airborne particle counts (0.3 and 2.5 um) were performed before and after the installation of GUVAPD, using standard techniques.
Results:
A significant 79% reduction of airborne bacterial colony-forming units (CFUs) from 130.8 to 27.2 CFUs (p < 0.0001) and a 68% reduction in settled surface bacterial CFUs from 10.2 to 5.7 CFUs (p = 0.016) were observed following installation of GUVPADs. Additionally, particulate matter measurements indicated a particle reduction of 47% and 75% (0.3 and 2.5 micron, respectively) after installation of GUVAPDs.
Conclusions:
These findings demonstrate that supplemental UV air treatment administered via GUVAPD effectively reduced both microbial and particulate contaminants in a complex room environment. Integrating GUVAPDs into current infection control strategies holds promising potential for improving patient and staff safety. Future research should explore the long-term effects and applicability of these systems in diverse clinical settings to further establish their efficacy in mitigating infections.
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