WAC 51-56-0600
Chapter 6 -- Water supply and distribution.
603.0Cross-Connection Control. Cross-connection control
shall be provided in accordance with the provisions of this
chapter. Devices or assemblies for protection of the public
water system must be models approved by the department of
health under WAC 246-290-490. The authority having
jurisdiction shall coordinate with the local water purveyor
where applicable in all matters concerning cross-connection
control within the property lines of the premises.
No person shall install any water operated equipment or
mechanism, or use any water treating chemical or substance, if
it is found that such equipment, mechanism, chemical or
substance may cause pollution or contamination of the domestic
water supply. Such equipment or mechanism may be permitted
only when equipped with an approved backflow prevention device
or assembly.
603.1 Approval of Devices or Assemblies. Before any device or
assembly is installed for the prevention of backflow, it shall
have first been approved by the authority having jurisdiction.
Devices or assemblies shall be tested for conformity with
recognized standards or other standards acceptable to the
authority having jurisdiction that are consistent with the
intent of this code.
All devices or assemblies installed in a potable water
supply system for protection against backflow shall be
maintained in good working condition by the person or persons
having control of such devices or assemblies. Such devices or
assemblies shall be tested in accordance with Section 603.3.3
and WAC 246-290-490. If found to be defective or inoperative,
the device or assembly shall be replaced or repaired. No
device or assembly shall be removed from use or relocated or
other device or assembly substituted, without the approval of
the authority having jurisdiction.
Testing shall be performed by a Washington state
department of health certified backflow assembly tester.
603.3.3 For devices and assemblies other than those regulated
by the Washington department of health in conjunction with the
local water purveyor for the protection of public water
systems, the authority having jurisdiction shall ensure that
the premise owner or responsible person shall have the
backflow prevention assembly tested by a Washington state
department of health certified backflow assembly tester:
(1) At the time of installation, repair or relocation;
and
(2) At least on an annual schedule thereafter, unless
more frequent testing is required by the authority having
jurisdiction.
603.4.6.1 Potable water supplies to systems having no pumps or
connections for pumping equipment, and no chemical injection
or provisions for chemical injection, shall be protected from
backflow by one of the following devices:
(1) Atmospheric vacuum breaker.
(2) Pressure vacuum breaker.
(3) Spill-resistant pressure vacuum breaker.
(4) Reduced pressure backflow preventer.
(5) A double check valve may be allowed when approved by
the water purveyor and the authority having jurisdiction.
603.4.10 Potable Water Make Up Connections to Steam or Hot
Water Boilers shall be protected by an air gap or a reduced
pressure principle backflow preventer.
603.4.12 Potable Water Supply to Carbonators shall be
protected by a listed reduced pressure principle backflow
preventer as approved by the authority having jurisdiction for
the specific use.
603.4.14 Backflow preventers shall not be located in any area
containing fumes or aerosols that are toxic, poisonous,
infectious, or corrosive.
603.4.16.1 Except as provided under Sections 603.4.16.2 and
603.4.16.3, potable water supplies to fire protection systems
that are normally under pressure, including but not limited to
standpipes and automatic sprinkler systems, except in one or
two family residential flow-through or combination sprinkler
systems piped in materials approved for potable water
distribution systems, shall be protected from back-pressure
and back-siphonage by one of the following testable devices:
1. Double check valve assembly.
2. Double check detector assembly.
3. Reduced pressure backflow preventer.
4. Reduced pressure detector assembly.
Potable water supplies to fire protection systems that are not
normally under pressure shall be protected from backflow and
shall meet the requirements of the appropriate standard(s)
referenced in Table 14-1.
603.4.23 Potable Water Supply to Swimming Pools, Spas and Hot
Tubs shall be protected by an airgap or a reduced pressure
principle backflow preventer when:
(1) The unit is equipped with a submerged fill line; or
(2) The potable water supply is directly connected to the
unit circulation system.
604.15 Plastic water service piping may terminate within a
building, provided the connection to the potable water
distribution system shall be made as near as is practical to
the point of entry and shall be accessible. Barbed insert
fittings with hose clamps are prohibited as a transition
fitting within the building.
608.5 Relief valves located inside a building shall be
provided with a drain, not smaller than the relief valve
outlet, of galvanized steel, hard drawn copper piping and
fittings, CPVC, or listed relief valve drain tube with
fittings which will not reduce the internal bore of the pipe
or tubing (straight lengths as opposed to coils) and shall
extend from the valve to the outside of the building with the
end of the pipe not more than two (2) feet (610 mm) nor less
than six (6) inches (152 mm) above the ground or the flood
level of the area receiving the discharge and pointing
downward. Such drains may terminate at other approved
locations. No part of such drain pipe shall be trapped or
subject to freezing. The terminal end of the drain pipe shall
not be threaded.
EXCEPTION:
Replacement water heating equipment shall only be required to provide a drain pointing downward from the relief valve to
extend between two feet (610 mm) and six inches (152 mm) from the floor. No additional floor drain need be provided.
610.4 Systems within the range of Table 6-5 may be sized from
that table or by the method set forth in Section 610.5.
Listed parallel water distribution systems shall be
installed in accordance with their listing.