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Backflow Prevention. Cross Connection Control. Cross Connection Control Charleston Mt. Pleasant Summerville. Polluted versus Contamination. Pollutant risk – color or odor Contaminant risk – health hazard. Polluted versus Contamination. Irrigation considered contamination risk
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Cross Connection Control Cross Connection Control Charleston Mt. Pleasant Summerville
Polluted versus Contamination • Pollutant risk – color or odor • Contaminant risk – health hazard
Polluted versus Contamination • Irrigation considered contamination risk • Pesticides and fertilizers
Cross Connection • Cross connection is any connection between potable and non-potable water
Backsiphonage • Backsiphonage is the reverse flow of water
Back pressure • Back pressure is continuous pressure back toward potable water • Elevation example
BACKFLOW PREVENTERS(Can be TESTED) Reduced pressure(RP) • Most pressure loss • $180 • Backpressure, pressure relief valve • Avoid water submersion of relief valve • 12 psi loss
BACKFLOW PREVENTERS(Can be TESTED) Reduced pressure(RP) • 12” above ground installation
BACKFLOW PREVENTERS(Can be TESTED) Pressure Vacuum Breaker (PVB) • Spring-loaded check valves and air-inlet prevent backsiphonageonly • Not intended for backpressure • $70 cost • 5 psi loss
BACKFLOW PREVENTERS(Can be TESTED) Pressure Vacuum Breaker (PVB) • 12” above highest head installation
BACKFLOW PREVENTERS(Can be TESTED) Double Check Valve • Spring loaded check valves only • No relief valve • 5 psi loss
BACKFLOW PREVENTERS(CANNOT be TESTED) Dual check valve • Spring loaded check valves only
BACKFLOW PREVENTERS(CANNOT be TESTED) Atmospheric Vacuum Breaker (AVB) • Float inlet • Not intended for continuous pressure • One for every valve, 6” above highest head • Cheapest • 2 psi loss
BACKFLOW PREVENTERS(CanNOT be TESTED) Anti-Siphon Valve • Control valve with built-in AVB
OTHER BACKFLOW PREVENTION AIR GAP • Breaks vacuum of backsiphonage
OTHER BACKFLOW PREVENTION HOSE BIB • Vacuum breaker attachment
INSTALLATION • Install after POC • A licensed plumber must tap into potable water system • Exception is homeowner that can tap into own water supply
INSTALLATION COPPER PIPE Two feet of copper (type K) in ground, before and after backflow preventer • Rigidity • Exposure
DHEC • South Carolina Department of Health and Environmental Control (DHEC) • http://www.scdhec.gov/environment/water/dwbflow.htm
Copper Pipe Sweating copper pipe
Copper Pipe • Sandpaper or emery cloth to clean pipe
Copper Pipe • Flux surfaces • Helps draw in solder
Copper Pipe • Dry-fit pipe and fitting
Copper Pipe • Heat pipe connection
Copper Pipe • Touch joint with solder • Melts and draws inside
TESTING • Tested annually by licensed tester • Certified BF inspector • DHEC, John Watkins 803-898-3567 • 3 day class ($225) • Equipment ($700) • http://www.scdhec.gov/environment/water/dwbflow.htm