Office of Research and Development Publications

Evaluating UV-C LED disinfection performance and investigating potential dual-wavelength synergy


Beck, S., H. Ryu, L. Boczek, J. Cashdollar, K. Jeanis, J. Rosenblum, O. Lawal, AND K. Linden. Evaluating UV-C LED disinfection performance and investigating potential dual-wavelength synergy. WATER RESEARCH. Elsevier Science Ltd, New York, NY, 109:207-216, (2017).


Emerging UV-LED technology is competitive with common mercury vapor lamps for inactivating bacteria and viruses during the water treatment process. The purpose of this study was to evaluate the effectiveness of several UV-LEDs in the inactivation of a few different types of bacteria and viruses. This work is important because it provides information on inactivation by UV-LED lamps, which are smaller, lighter, and less fragile than mercury vapor lamps. Water utilities that are deciding on a water treatment option, as well as their state and regional regulators, could use this work to help their decision.


This study evaluated ultraviolet (UV) light emitting diodes (LEDs) emitting at 260 nm, 280 nm, and the combination of 260|280 nm together for their efficacy at inactivating Escherichia. coli, MS2 coliphage, human adenovirus type 2 (HAdV2), and Bacillus pumilus spores; research included an evaluation of genomic damage. Inactivation by the LEDs was compared with the efficacy of conventional UV sources, the low-pressure (LP) and medium-pressure (MP) mercury vapor lamps. The work also calculated the electrical energy per order of reduction of the microorganisms by the five UV sources. For E. coli, all five UV sources yielded similar inactivation rates. For MS2 coliphage, the 260 nm LED was most effective. For HAdV2 and B. pumilus, the MP UV lamp was significantly more effective than the LP UV and UVC LED sources. When considering electrical energy per order of reduction, the LP UV lamp was the most efficient for E. coli and MS2, and the MPUV and LPUV were equally efficient for HAdV2 and B. pumilus spores. Among the UVC LEDs, the 280 nm LED unit required the least energy per log reduction of E. coli and HAdV2. The 280 nm and 260|280 nm LED units were equally efficient per log reduction of B. pumilus spores, and the 260 nm LED unit required the lowest energy per order of reduction of MS2 coliphage. The combination of the 260 nm and 280 nm UV LED wavelengths was also evaluated for potential synergistic effects. No dual-wavelength synergy was detected for inactivation of all four microorganisms, nor for DNA/RNA damage.

Record Details:

Product Published Date: 02/01/2017
Record Last Revised: 06/02/2020
OMB Category: Other
Record ID: 336939