In this study the effects of mixing using static mixers for the inactivation of Cryptosporidium oocysts were examined. The static mixers used were a 2 and 6 element helical mixer and the stata tube. Empty pipe, batch and jar tests were completed to examine the effects of limited mixing. The disinfectants tested were chlorine at 5 mg/l and pH 6,7, and 8 and chlorine dioxide at 2 mg/L and pH 8. The infectivity assay used was cell culture with Madin Darby canine kidney cells. Includes 13 references, table, figures.