Design of UVC disinfection system for public transport by optical FEM

Abstract

The objective of this study was to develop a systematic procedure for implementing Ultraviolet-C (UVC) irradiation in a 21-seat minibus, aiming to improve efficiency of the disinfection system. Utilizing the ANSYS SPEOS® optical design software, a comprehensive 3D simulation of UVC radiation at 280 nm was conducted, covering the passenger seating area. The simulation's objective was to minimize the number of UVC LED lamps needed within the minibus while ensuring a UVC radiation exposure of 15 minutes duration and achieving a log reduction exceeding 1.0 log10 (90%). The simulation determined that a minimum of 9 UVC LED lamps is required for effective disinfection. To validate this simulation-driven approach, Escherichia coli (E. coli) was used to test performance after actual UVC lamp installation. Results from the real-installation disinfection, conducted under optimal parameters, conclusively demonstrated 1.0 log10 (90%) reduction in E. coli and 2.0 log10 (99%) inactivation.