Effect of Humidity on Sterilization Using Photocatalyst

Copyright: © 2014 Shintani H. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The photocatalyst equipment consists of a titanium dioxlde (TiO2) plate and an ultraviolet lamp. The authors studied if the photocatalyst equipment is practically applicable in sterilizing environmental microorganisms in the health care facility. The number of microorganisms was compared among no sterilization (control), UV alone and the photocatalyst sterilization. As a result, a statistical difference was observed between control and the photocatalyst sterilization against airborne microorganisms (p<0.01) but not against surface microorganisms (p>0.2). In addition, no significant difference between UV alone and photocatalyst (p>0.2), indicating the major function of photocatalyst is not OH radicals, but UV exposure, however OH radicals also contribute when humidity increased because OH radicals increased when water increased. OH radicals are from water.