Ultraviolet C irradiation: A promising approach for the disinfection of public spaces?

• Published in: The Science of the total environment 2023-06, Vol.879, p.163007-163007, Article 163007
• Main Authors: Pereira, Ana Rita, Braga, Daniel F.O., Vassal, Mariana, Gomes, Inês B., Simões, Manuel
• Format: Article
• Language: English
• Subjects: air; COVID-19 - prevention & control; disinfection; Disinfection - methods; environment; equipment maintenance and repair; human health; Humans; irradiation; markets; Microbial contamination; pandemic; public transportation; risk; SARS-CoV-2; Severe acute respiratory syndrome coronavirus 2; sustainable technology; ultraviolet radiation; Ultraviolet Rays; UVC devices; UVC disinfection; UVC safety
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2023.163007

Ultraviolet irradiation C (UVC) has emerged as an effective strategy for microbial control in indoor public spaces. UVC is commonly applied for air, surface, and water disinfection. Unlike common 254 nm UVC, far-UVC at 222 nm is considered non-harmful to human health, being safe for occupied spaces, and still effective for disinfection purposes. Therefore, and allied to the urgency to mitigate the current pandemic of SARS-CoV-2, an increase in UVC-based technology devices appeared in the market with levels of pathogens reduction higher than 99.9 %. This environmentally friendly technology has the potential to overcome many of the limitations of traditional chemical-based disinfection approaches. The novel UVC-based devices were thought to be used in public indoor spaces such as hospitals, schools, and public transport to minimize the risk of pathogens contamination and propagation, saving costs by reducing manual cleaning and equipment maintenance provided by manpower. However, a lack of information about UVC-based parameters and protocols for disinfection, and controversies regarding health and environmental risks still exist. In this review, fundamentals on UVC disinfection are presented. Furthermore, a deep analysis of UVC-based technologies available in the market for the disinfection of public spaces is addressed, as well as their advantages and limitations. This comprehensive analysis provides valuable inputs and strategies for the development of effective, reliable, and safe UVC disinfection systems. [Display omitted] •UV-C emerges as an alternative to harmful and (eco)toxic chemical disinfectants.•Far-UV-C can eliminate pathogens in spaces with simultaneous human presence.•Autonomous UV-C-based devices/robots reduce manual work and process costs.•No consensus exists on UV-C safety and human exposure.