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During the study, each of six loops received continuous application of one
of the following disinfectants: chlorine (as sodium hypochlorite), electro-
chlorination, chlorine dioxide, monochloramine, ozone, or copper/silver.
The seventh loop was used as the negative (untreated) control. Performance
evaluation of these disinfectants was based on their ability to control
Legionella
, protozoa and biofilms. Figure 3 shows the rig.
Figure 3. Domestic water supply simulation unit. 1: galvanized steel
coupons, 2: mild steel coupons, 3: copper coupons, 4: brass coupons, 5 and
8: glass beads for biofilm monitoring, 6 and 7: PVC coupons for biofilm
monitoring, 9: re-circulation pump, 10 and 11: solenoid valves, 12: non-
return valve, 13: temperature probe, 14: pressure gauge, 15: air trap, 16:
point of injection of disinfectants, 17: connection to the calorifier. The water
temperature during all experiments was 35 °C and the pH was 8.5.
Figure 3
