A Critical Review on Ultraviolet Disinfection Systems against COVID-19 Outbreak: Applicability, Validation, and Safety Considerations

Abstract

The global health-threatening crisis from the COVID-19 pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), highlights the scientific and engineering potentials of applying ultraviolet (UV) disinfection technologies for biocontaminated air and surfaces as the major media for disease transmission. Nowadays, various environmental public settings worldwide, from hospitals and health care facilities to shopping malls and airports, are considering implementation of UV disinfection devices for disinfection of frequently touched surfaces and circulating air streams. Moreover, the general public utilizes UV sterilization devices for various surfaces, from doorknobs and keypads to personal protective equipment, or air purification devices with an integrated UV disinfection technology. However, limited understanding of critical UV disinfection aspects can lead to improper use of this promising technology. In this work, fundamentals of UV disinfection phenomena are addressed; furthermore, the essential parameters and protocols to guarantee the efficacy of the UV sterilization process in a human-safe manner are systematically elaborated. In addition, the latest updates from the open literature on UV dose requirements for incremental log removal of SARS-CoV-2 are reviewed remarking the advancements and existing knowledge gaps. This study, along with the provided illustrations, will play an essential role in the design and fabrication of effective, reliable, and safe UV disinfection systems applicable to preventing viral contagion in the current COVID-19 pandemic, as well as potential future epidemics.

Quantitative evaluation of SARS-CoV-2 inactivation using a deep ultraviolet light-emitting diode

“…While the biological effects of DUV light have been widely proven across different types of viruses 14,[16][17][18][19][28][29][30][31][32] , the precise mechanism by which the DUV light inactivates viruses remains to be elucidated 19 . Several studies reported that virus inactivation by DUV irradiation is primarily caused by the photochemical reactions of nucleic acids 19,33,34 .…”

Quantitative Evaluation of SARS-CoV-2 Inactivation Using a Deep Ultraviolet Light-Emitting Diode

“…While the biological effects of DUV light have been widely proven across different types of viruses [14,[16][17][18][27][28][29][30][31], the precise mechanism by which the DUV light inactivates viruses remains to be elucidated [18]. Several studies reported that virus inactivation by DUV irradiation is primarily caused by the photochemical reactions of nucleic acids [18,32,33].…”

The impact of far-UVC radiation (200–230 nm) on pathogens, cells, skin, and eyes – a collection and analysis of a hundred years of data

“…The antimicrobial properties of ultraviolet radiation from mercury vapor lamps are well known and have been applied for over a hundred years [ 1 ]. They have also proven to be effective against coronaviruses [ 2 ], [ 3 ].…”