UV-C and Far UV for Microbial Decontamination in Air and on Surfaces
Jun 20, 2024
Introduction
Ultraviolet (UV) technology has long been recognized for its effectiveness in microbial decontamination. Recently, Far UV has emerged as a promising alternative, offering unique advantages. This blog explores the differences between UV and Far UV for microbial decontamination, focusing on their effectiveness in air and surface disinfection.
Figure 1: UV Spectrum and Wavelength.
Understanding UV and Far UV
UV radiation spans a spectrum of wavelengths, typically divided into three categories: UV-A, UV-B, and UV-C. Each has unique properties:
UV-A: The longest wavelength ranges from 320 to 400 nanometers (nm). It is least effective at killing microbes but is widely present in sunlight and used in tanning beds.
UV-B: Ranging from 280 to 320 nm, UV-B is more energetic and can cause skin burns. It's also useful for vitamin D synthesis in humans.
UV-C: The most germicidal of the UV wavelengths, UV-C ranges from 100 to 280 nm. It's commonly used in sterilization due to its effectiveness in inactivating pathogens. Most UV-C devices fall within the 260-280nm range.
Far UV, typically at a wavelength around 222 nm, falls within the UV-C range but has distinct characteristics. Unlike conventional UV-C radiation, which can cause skin and eye irritation, Far UV is safer for human exposure due to its shallow penetration. This makes it suitable for continuous use in occupied spaces.
Microbial Decontamination in Air
Airborne pathogens pose significant health risks, particularly in shared spaces. UV and Far UV are both effective in air disinfection. UV systems use lamps or LEDs to irradiate the air passing through a ventilation system or within a room. These systems are effective but pose risks to human health if misused. Far UV, on the other hand, offers continuous irradiation without risking human exposure. Studies show that Far UV is effective against many airborne microbes, including viruses and bacteria, making it a promising solution for air decontamination.
Figure 2: UVC Relative Dosing Requirements for deactivation of microbes (260 nm).
Microbial Decontamination on Surfaces
Surfaces can harbor pathogens, contributing to the spread of infections. UV light has been widely used for surface disinfection, particularly in healthcare settings. It's effective but can be harmful if misused. Far UV offers similar efficacy but with improved safety, making it suitable for continuous use in high-touch areas like desks, door handles, and medical equipment. Both methods are effective for surface disinfection, but Far UV allows for safer, on-demand disinfection in occupied spaces.
Figure 3: Far UV Relative absorbance for various pathogens showing that 222nm has a higher absorbance that that of 260nm.
Applications and Industry Use
UV and Far UV technologies have diverse applications across the healthcare, hospitality, and transportation industries. UV is used for terminal cleaning in healthcare, while Far UV can disinfect high-touch areas during regular operations. In hospitality, UV is used for room cleaning, while Far UV can maintain cleanliness in common areas. The transportation industry also benefits from these technologies, as they can disinfect cabins, waiting areas, and equipment. Both technologies offer unique advantages, and their use depends on the specific needs of each industry.
ARE Labs' Role in Decontamination Testing
ARE Labs provides comprehensive testing services to ensure the effectiveness of UV and Far UV technologies. Our lab specializes in aerosol and surface testing, offering advanced analyses like HPLC. We help clients validate their decontamination strategies, providing data-driven insights for effective disinfection. Businesses can leverage our expertise to ensure their decontamination solutions meet industry standards.
Conclusion
UV and Far UV technologies play crucial roles in microbial decontamination. While UV has a proven track record, Far UV offers enhanced safety for continuous use. Both methods are effective for air and surface disinfection, with applications across various industries. ARE Labs can assist businesses in validating their decontamination solutions, ensuring effective and safe microbial control.
