The efficacy of three commercial ultraviolet (UV) units - IWG 1-M-15, Trojan AUV 705, and Atlantic MP22 - was quantified using the biodosimetric method with flow-through test facility experiments outlined in the NSF 55-1991 Standard as a guideline. The inactivation achieved across each UV reactor was quantified and compared to the UV dose-response curve to determine the UV dose delivered by the unit. Batch irradiation experiments performed with the Collimated Beam Apparatus (CBA) established the UV dose-response curve for each microorganism tested - Bacillus subtilis spores (strains ATCC 9372, 1A1), and MS2 bacteriophage (ATCC 15597-B1). Results show that at a flow rate of 2.5, 5.0, and 10-gpm, the International Water Guard (IWG 1-M-15) unit delivered approximately 70, 40-45, and ~35-mJ/cm2, respectively; and, the Trojan AUV 705 unit delivered 70, 40, and 30-mJ/cm2. At flow rates of 5, 6, and 10-gpm, the Atlantic Mighty Pure (M22) unit delivered approximately 40, 28, and 24-mJ/cm2. With the error limits of the results, all units met or exceeded the manufactures claims. Includes 5 references, tables, figures.
Keywords: Flow; Standards; Performance; Microorganisms; Bacteriophages; Reactors; Ultraviolet Disinfection
