"RPZ" device, as it is commonly
referred to, is a backflow prevention device
which is used to prevent "backflow"
of foreign liquids and other matter into the
potable supply of water which could result
in contamination. Backflow can occur when
the pressure on our system is less then the
pressure on a customer's system.
backflow prevention device is used to protect
water supplies from contamination or pollution.
Many types of backflow prevention devices
also have test ports so that they can be tested
or examined to ensure that they are functioning
properly. Many states and/or local municipalities
actually require annual testing of such devices.
A check valve is a common form of a backflow
prevention protects the potable water system
from minor, moderate, and severe hazards.
There are over 10,000 reported cases of backflow
contamination each year. Some cases can be
fatal. Backflow devices are required by law
where needed and must be installed in accordance
with plumbing or building codes. A backflow
assembly has test cocks and shut-off valves
and must be tested each year, if relocated
or repaired, and when installed.