MPhil in Environmental Science, Policy and Management - Light-based technology for surface disinfection
9:00am - 10:00am
Room 2302 (Lifts 17-18) 2/F Academic Building
The number of hospital acquired infection (HAI) relating to multidrug-resistant microorganisms has been rising throughout the past years. Contact with contaminated surfaces is one of the major transmission routes. Despite the fact that conventional chemical disinfectants can help prevent such transmission, they are only effective when applied properly and frequently. Moreover, microbial tolerance and surface corrosion are the major concerns of using chemical disinfectants. There is a demand for finding an alternative approach to disinfect surfaces. In this research, we aim at developing a new light-based device that is safe for surface disinfection and optimizing its deployment. UVC (280nm), 405nm and 470nm were chosen and assessed on their bactericidal efficacy by bactericidal tests. Comparison between continuous and pulsed lights as well as studies of parametric factors and interaction among lightings with different wavelengths were carried out for optimization of the system. The results demonstrated the bactericidal effect of all the lightings and suggested that pulsed light at 1 Hz was a more efficient choice than continuous light. As well, synchronous light was found to reduce the bactericidal effect of mix lightings while asynchronous pre-exposure of 405nm to UVC (280nm) and alternative exposure of 470nm with 280nm could enhance the bactericidal performance compared to UVC light. The evaluation of the combined lightings also showed its higher bactericidal effect when compared to UVC. Based on the results, a light disinfection system was fabricated and its bactericidal performance, material compatibility and biosafety were assessed. The system was able to achieve high bactericidal rate and at the same time did not cause high risk of material damage and safety issue.
Event Format
Candidate
Miss WONG Ngai Ki Frances
Language
English
English
Recommended For
General public
Faculty and staff
UG students
Contact
Should you have any questions, please feel free to contact ENVR at envr@ust.hk.