Page 102 - Microsoft Word -Cow Book 10-06-09 final update.doc

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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