[Clinical uses of ultraviolet light radiation]

The main use of ultraviolet light radiation in hospitals is for the disinfection of the air. A study was made of the disinfecting efficiency of indirect ultraviolet radiation (lifts, cleaning of bedding), direct irradiation of rooms overnight or after use, ultraviolet curtains (irradiation of the whole width of passages, doorways and entrances) and ultraviolet irradiation of the filter of air-conditioners. The results are analysed. With the exception of the barrier technique ultraviolet light irradiation did not substantially reduce the number of micro-organisms in the air. Knowledge of the limitations and side-effects of this technique, control of the intensity of ultraviolet irradiation and bacterial counts are regular intervals are some of the factors that determine the success of this mode of disinfection. Detailed studies of the acceptable upper limits of the number of micro-organisms in the air of hospital wards and operating theatres is of prime importance for evaluating the effectiveness of air-disinfection by ultraviolet light irradiation.