A Study of Active Oxygen Sterilization System Used an Ultraviolet Irradiation

An advanced sterilization system using exited oxygen species, such as exited singlet oxygen molecules (1O2) and exited singlet atomic oxygen (O(1D)), by ultraviolet irradiations was investigated. Viability of Geobacillus stearothermophilus spore was estimated with a biological indicator (BI) in the active oxygen sterilization (AOS) system. Survival curves of Geobacillus stearothermophilus spore showed exponential reduction. Decimal reduction time (D-value) was found to be 6.8 min., when the active oxygen was irradiated by four or five UV lamps. It was found that Geobacillus stearothermophilus spore was not sterilized by the UV irradiation, but the active oxygen irradiation. We believe that this sterilization system can be applied for medical device sterilization as a new sterilizer.