1997 年 12 巻 3 号 p. 174-176
Studies of the effectiveness of compact size ultraviolet (UV) air disinfection system against airborne bacteria were conducted in patient rooms with 3.15m×5.0m, 3.8m ceiling. The air disinfection systems were activated 24 hrs per one day. Four points of air sampling of 8 ft3 in volume were performed every one week for 3 months. No limitations were applied to incoming/outgoing of patients and medical staffs.
Mean colony count of airborne organisms of air samples with UV air disinfection systems off was 4.0±1.9 CFU/ft3, and reduced to 1.4±1.0 CFU/ft3 after UV air disinfection systems on. Rates of 65% reduction of microorganisms were observed under the condition with air disinfection systems activated (p<0.01). Under existence of patients with infected wound, mean colony count of organisms was still increased, from 2 to 10 times higher, after the treatment of wounds.