Efficacy of a far-ultraviolet-C light technology for continuous decontamination of air and surfaces

A wall-mounted, far-ultraviolet-C light technology reduced aerosolized bacteriophage MS2 by >3 log10 plaque-forming units within 30 minutes. Vegetative bacterial pathogens on steel disk carriers in the center of the room were reduced by >3 log10 after 45 minutes of exposure, but Candida auris and Clostridioides difficile spores were not.

Effectiveness of ultraviolet-C light treatment of shoes in reducing the transfer of pathogens into patient rooms by shoes of healthcare personnel

Contaminated shoes are a potential vector for dissemination of healthcare-associated pathogens. We demonstrated that healthcare personnel walking into patient rooms frequently transferred pathogens from their shoes to the floor. An 8-second treatment of shoes with a UV-C decontamination device significantly reduced the frequency of transfer of vegetative bacterial pathogens.

Real-World Evidence on the Effectiveness of Plexiglass Barriers in Reducing Aerosol Exposure

Reprinted with permission, Cleveland Clinic Foundation ©2022. All Rights Reserved.

BACKGROUND

Barriers are commonly installed in workplace situations where physical distancing cannot be maintained to reduce the risk for transmission of respiratory viruses. Although some types of barriers have been shown to reduce exposure to aerosols in laboratory-based testing, limited information is available on the efficacy of barriers in real-world settings.

METHODS

In an acute care hospital, we tested the effectiveness of in-use plexiglass barriers in reducing exposure of staff to aerosolized particles. A nebulizer was used to release 5% NaCl aerosol 1 meter from staff members with and without the barrier positioned between the point of aerosol release and the hospital staff. Particle counts on the staff side of the barrier were measured using a 6-channel particle counter. A condensed moisture (fog) generating device was used to visualize the airflow patterns.

RESULTS

Of 13 in-use barriers tested, 6 (46%) significantly reduced aerosol particle counts detected behind the barrier, 6 (46%) reduced particle counts to a modest, non-significant degree, and 1 (8%) significantly increased particle counts behind the barrier. Condensed moisture fog accumulated in the area where staff were seated behind the barrier that increased particle exposure, but not behind the other barriers. After repositioning the ineffective barrier, the condensed moisture fog no longer accumulated behind the barrier and aerosol exposure was reduced.

CONCLUSION

In real-world settings, plexiglass barriers vary widely in effectiveness in reducing staff exposure to aerosols, and some barriers may increase risk for exposure if not positioned correctly. Devices that visualize airflow patterns may be useful as simple tools to assess barriers.