AWWA PATH56562

In search of viral indicators for control of radiation induced water disinfection processes, the inactivation of the bacteriophages PHI X 174 (ssDNA virus), MS 2 (ssRNA virus) and B40-8 (dsDNA virus) in tap water by means of non- ionizing (UV 253.7 nm) and ionizing radiation was studied. It was found that none of the bacteriophages investigated may serve as viral indicators for both radiation processes since in water MS 2 phages which are rather resistant to ultraviolet (UV) radiation were found to be sensitive to ionizing radiation. However, in water PHI X 174 phages which were found to be rather resistant to ionizing radiation are known to be quite sensitive to UV radiation. Therefore, when UV radiation is applied for water disinfection MS 2 would be an appropriate viral indicator while PHI X 174 should be used when ionizing radiation is the disinfectant. Includes 5 references, tables, figures.