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tap.Rather, correctiveactionsare thatwhich isdone to immediatelycorrect
anydeviation from critical control limits.
HazardControl inPotableWaterSystems
Supplemental hazard control is often, but not always, necessary for the
control of microbial hazards in the potable water system of US buildings.
Water Management Teams should always begin with the simplest, safest
andmost cost-effectiveoption for buildingwater systemhazard control.
There is ample evidence from laboratory tests, pilot scale simulations
andpractical real-work experience that sodiumhypochlorite treatment of
buildingwater systems is often the simplest, safest andmost cost-effective
option. In chlorinated building water systems where microbial fouling
persists, usually the problem is due to lack of adequate distribution of
disinfectant throughout the facility.
Pilot-scalePotableBuildingWaterSystem
A study to compare the efficiency of different disinfectants applicable
to
Legionella
control in domestic potable water systems was undertaken.
A domestic water supply simulation unit that allowed simulation of real-
world conditions was developed for this purpose.The system, consisting
of seven identical rigs, was used to compare treatment efficiency under
equivalent conditions of system design, materials, hydraulics, water
quality, temperature and initial contamination. The water temperature
during all experiments was 35 °C and the pH was 8.5. Other details of
water chemistry and operating conditions were set to simulate building
water system conditions andhave beenpreviouslydescribed (Loret 2005).
