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II. PRESSURE TYPE-
Designed for installation on water supply lines normally under constant pressure.
This device protects against back-siphonage back-flow only. Must be installed 12
inches higher than what it is trying to protect. It is allowed in lines that are either
under intermittent pressure or constant pressure. Therefore it may have shut off
valves located after it.
Spill Resistant Vacuum Breaker (SVB)/(PVB)
High hazard
Back siphonage
Continuous pressure‐can have valves downstream
Indoor use
Spring loaded float disc
Test cocks
Installed 12 in higher than what you are trying to protect
Installed vertically
Checked annually, at installation, & taken in/out of service
Chemical tower
PVB is used outside
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