[Evaluation of chlorine dioxide concentrations needed to effectively control contamination by Legionella spp in hospital hot water distribution systems]. / La determinazione della concentrazione efficace di biossido di cloro (ClO2) per il controllo della contaminazione da Legionella spp nei circuiti dell'acqua calda sanitaria.

This aim of the study was to identify effective levels of ClO2 for control of Legionella spp. contamination in the hot water (45-55 °C.) distribution system of a 579-bed hospital in Ravenna (Italy). Overall, 663 hot water samples were collected from the hospital's sinks and shower taps and were analyzed. Trend line analysis, which describes the trend in the number of positive samples collected according to disinfectant concentration, shows that the lowest number of positive samples was achieved with concentrations of ClO2 between 0.22 and 0, 32 mg /l.