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. 2021 Dec;49(12):1506-1510.
doi: 10.1016/j.ajic.2021.08.003. Epub 2021 Aug 12.

Evaluating and contextualizing the efficacy of portable HEPA filtration units in small exam rooms

Stephen Pirkle  1 , Sandy Bozarth  2 , Natasha Robinson  2 , Wanda Hester  2 , LaurieAnn Wagner  2 , Sabrina Broome  2 , Kim Allen  2 , Supriya Mannepalli  3
Affiliations

Evaluating and contextualizing the efficacy of portable HEPA filtration units in small exam rooms

Stephen Pirkle et al. Am J Infect Control. 2021 Dec.

Abstract

Background: Ambulatory clinics attend to COVID-19 patients, often in spaces with less than ideal ventilation. Testing and treatments can often include aerosol-generating procedures. Portable high efficiency particulate air (HEPA) filtration units have been used to remove airborne contaminants in these areas.

Methods: A particle counter was used to evaluate the effectiveness of portable HEPA filtration units when a proxy airborne contaminant (powder) was actuated into the air. The Center for Disease Control and Prevention's (CDC) Airborne Contaminant Removal table served as a basis for initial particle readings at 6 minutes.

Results: Percent decrease was calculated post powder actuation at the 6-minute and 12-minute mark. There was a statistically significant decrease in smaller particles at the 6-minute and 12-minute mark when the HEPA filtration units were used.

Conclusion: As an adjunct infection control intervention, portable HEPA filtration units can make outpatient exam rooms safer for patients and staff by decreasing cumulative airborne particles.

Keywords: Air scrubber; Airborne transmission; Engineering controls; Exam room; Portable HEPA filtration; Portable HEPA units.

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Figures

Fig 1
Fig 1
Representation of the layout in an interventional room.
Fig 2
Fig 2
Interventional Rooms Where HEPA filtration was used. Particles < 5 µm.
Fig 3
Fig 3
Interventional Rooms where HEPA filtration was used. Particles ≥ 5 µm.
Fig 4
Fig 4
Control Room-Where NO HEPA Filtration was used. Particles < 5 µm.
Fig 5
Fig 5
Control Room-Where NO HEPA filtration was used. Particles ≥ 5 µm.
See this image and copyright information in PMC

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