Effects of UV intensity and water turbidity on microbial indicator inactivation

The effects of UV intensity and turbidity on selected microbial indica tor inactivation were investigated. Results showed that UV disinfection was effe ctive in killing all the selected microbial indicators, the resistance order of the microorganisms was as follows: MS-2 coliphage > Bacillus subtilis > E. coli > Staphylococcus aureus and Candida albicans. UV intensity had influence on the inactivation of all the microorganisms, high UV disinfection efficency was obtai ned with higher UV intensity. Turbidity had impact on the bacteria inactivation rate, but there was no evidence that turbidity had any negative contribution to MS-2 coliphage. Under the same UV dosage, higher UV intensity could overcome the negative influence of turbidity on UV performance, enhanced microorg- anism ina ctivation effect in turbidity water.