A new UVC-LED system for disinfection of pathogens generated by toilet flushing

A new disinfection system utilizing UVC-LED irradiation was developed. The system was affixed to the toilet seat, and it was challenged by three bacteria strains. Different configurations were tested: 3-LEDs, 5-LEDs (two variants), and 8-LEDs. To determine the arrangement designs of LEDs with the optimum efficacy, two variants of 5-LEDs configurations were additionally considered-uniform and concentrated (2-sided) distributions. It was noticed that disinfection efficacy initially increased with the number of LEDs, but with 8-LEDs, the trend became almost non-obvious for surface disinfection and just marginally increased for airborne disinfection. The mean efficiencies for the surface disinfection ranged from 55.17 +/- 23.89% to 72.80 +/- 4.13% for E. coli; 36.65 +/- 2.99% to 50.05 +/- 13.38% for S. typhimurium; and 8.81 +/- 3.23% to 39.43 +/- 9.33% for S. epidermidis. Likewise, the mean efficiencies for airborne disinfection ranged from 42.17 +/- 8.18% to 70.70 +/- 4.80%; 40.40 +/- 17.90% to 58.31 +/- 13.87%; and 24.16 +/- 3.81% to 42.79 +/- 10.20% for E. coli; S. typhimurium; and S. epidermidis, respectively. Furthermore, the efficacy of the uniform irradiation was nearly twice that of the concentrated irradiation for surface disinfection and 17.70% higher for airborne disinfection, when tested against E coli. Collectively, these very promising results showcased that this compact, sustainable, and localized disinfection system has a high potential for the next generation of disinfection devices.

Automated summary

A new disinfection system using UVC-LED irradiation was developed and tested with varying LED configurations, revealing that more LEDs did not necessarily improve efficacy, and uniform irradiation performed better than concentrated irradiation. These results demonstrate high potential for the next generation of disinfection devices.