Low-maintenance, consumables-free disinfection by UV-C LEDs

Ultraviolet (UV) disinfection has long been known as a chemical-free disinfection process capable of producing a 6-log reduction effect. Conventional UV sources, often called germicidal lamps, consist of a mercury amalgam encapsulated within a quartz sleeve and function by a plasma discharge mechanism; critically, the low durability and mercury content of these devices have limited their application within space environments. UV-C LEDs can produce the same disinfection effect as conventional germicidal lamps without many of the key drawbacks. Based on semiconductor technology, UV-C LEDs provide a high durability, DC-powered, long lifetime, mercury-free, small footprint, and low maintenance solution to the disinfection of air, water, and surfaces. As semiconductor devices UV-C LEDs are ideal for integration into reactive and controllable systems with real-time feedback, and capable of response times as short as 10 ns. UV-C LEDs have already been deployed on-orbit within the Microgravity Science Glovebox (MSG), are included within the Advanced Closed Loop System (ACLS), and perform a key function of the BIOWYSE system breadboard. We present a background to the technology, the development of UV-C LEDs to their current capabilities, and how these devices may be integrated into next-generation disinfection systems.