How many inches of head is 1 psi?
27 3/4”
Backpressure?
Anything downstream that creates greater pressure than supply pressure.
Backsiphonage
Sub atmospheric pressure in the water system
2 types of cross-connection?
Direct and indirect
What 2 things constitute a direct cross connect?
Backsiphonage and backpressure?
What constitutes an indirect cross connection?
Only Backsiphonage is possible
Non health hazard is a
Pollutant
A health hazard is a
Contaminant
Hany many pounds per square inch does one cubic foot of water exert?
0.433 psi
How much pressure is required for a DCV to operate?
1 psi
How much psi does it take to activate a RP relief valve?
2 psi
What can’t Double Checks be used to protect against?
Contaminants
What is the minimum and maximum elevation to install an RP and DC?
12” from the bottom of the assembly (critical elevation) to the grade. 36” maximum
How many test cocks does PVB have?
2
What is required if an RP and DC is installed higher than 36” above grade?
A platform for you to stand on
What can’t pressure vacuum breakers be used to prevent?
Backpressure
What’s the minimum install distance of an AVB?
6” above grade
What’s the minimum install distance of a PVB?
12” above the highest sprinkler
What can’t AVBs protect against?
Back pressure
What size must the RP be relative to the meter?
Same or 1 size up
Internal protection is also
Isolation
Meter protection is also
Containment
