The protective device required shall depend on the degree of
hazard as tabulated below:
A. At the service connection to any premises where there is an auxiliary
water supply handled in a separate piping system with no cross-connection,
the public water supply shall be protected by an approved double check-valve
assembly.
B. At the service connection on any premises on which there is an auxiliary
water supply where cross-connections are known to exist or where it
is unknown if cross-connections exist, the public water supply system
shall be protected by an air-gap separation or an approved reduced
pressure principle backflow prevention device.
C. At the service connection to any premises on which a substance that
would be objectionable, but not hazardous to health if introduced
into the public water supply, is handled so as to constitute a cross-connection,
the public water supply shall be protected by an approved double check-valve
assembly.
D. At the service connection to any premises on which a substance of
unusual toxic concentration or danger to health is or may be handled,
but not under pressure, the public water supply shall be protected
by an air-gap separation or an approved reduced pressure principle
backflow prevention device. This device shall be located as close
as practicable to the water meter, and all piping between the water
meter and receiving tanks shall be entirely visible.
E. At the service connection to any premises on which any material dangerous
to health or any toxic substance in toxic concentration is or may
be handled under pressure, the public water supply shall be protected
by an air-gap separation. The air gap shall be located as close as
practicable to the water meter, and all piping between the water meter
and receiving tanks shall be entirely visible. If these conditions
cannot be reasonably met, the public water supply shall be protected
with an approved reduced pressure principle backflow prevention device,
provided that the alternative is acceptable to the water purveyor.
F. At the service connection to any sewage treatment plant or sewage
pumping station, the public water supply shall be protected by an
air-gap separation. The air gap shall be located as close as practicable
to the water meter, and all piping between the water meter and receiving
tanks shall be entirely visible. If these conditions cannot be reasonably
met, the public water supply shall be protected with an approved reduced
pressure principle backflow prevention device.
G. At the service connection to any premises not covered by Subsections
A through
F above, the public water supply shall be protected with an approved single check-valve assembly.
It shall be the duty of the water user on any premises on account
of which backflow protective devices are installed to have competent
inspections made at least once a year or more often in those instances
where successive inspections indicate repeated failure. These devices
shall be repaired, overhauled or replaced at the expense of the water
user whenever they are found to be defective. These tests shall be
performed by a qualified backflow prevention device tester, and all
test results will be provided to the water purveyor within 72 hours
after the test is made. Records of such tests, repairs and overhauls
shall also be kept and made available to the water purveyor and the
local Health Department upon request.