OBSERVATION ON EFFICACY OF ULTRAVIOLET RAYS IN DISINFECTION OF AIR ON BURN WARD

In order to know the efficacy of ultraviolet rays in disinfection of air on burn ward, sampling by on-the-spot natural bacteria plate sedimentation method was used to observe different duration and frequency of ultraviolet irradiation. Results: Direct ultraviolet lamp irradiation for 30 min could result in rate of up to standard of class-Ⅱ environment standard (total bacterial count in air ≤200 cfu/m3) on burn ward air attained 70% and irradiation for 60 min resulted in up-to-standard rate of 80%. Three hours after discontinuation of ultraviolet irradiation, the bacterial count of air returned to the level before disinfection, it is, therefore, required to carry out ultraviolet disinfection of burn ward air for longer than 30 min each time and irradiation 6 times daily.