QUANTITATION OF FREE-LIVING AMEBAS AND BACTERIAL-POPULATIONS IN EYEWASH STATIONS RELATIVE TO FLUSHING FREQUENCY

This study investigated the concentration of amoebic and bacterial pop ulations in eyewash station water relative to various flushing regimen s: Amoebae concentrations averaged approximately 200 amoebae/100 mL in 13 of 15 stations positive for amoebae and consisted of Hartmannella and Acanthamoeba. Bacterial concentrations ranged from 10(0) to more t han 10(5) colony forming units per mt. Amoebic concentrations differed notably between stations located in Buildings X and Y (p < 0.0001). F urther study indicated that removal of diffusing screens did not subst antially change (p > 0.05) the concentration of-amoeba. Amoebic and ba cterial concentrations temporarily decreased with he various flushing regiments tested. Lower amoebic concentrations were not sustained by a weekly 3-minute or a monthly 1-minute flushing regimen. However, week ly 3-minute flushes appeared to be more effective in maintaining lower ed bacterial concentrations (p < 0.0001).