Louisiana Administrative Code
Title 51 - PUBLIC HEALTH-SANITARY CODE
Part XIV - Plumbing
Chapter 6 - Water Supply and Distribution
Section XIV-609 - Protection of Potable Water Supply

1. Backflow. The potable water supply including, but not limited to, the water supply system, the water service pipe, and the water distribution system shall be protected against backflow. Every water outlet shall be protected from backflow, preferably by having the outlet end from which the water flows spaced a distance above the flood-level rim of the receptacle into which the water flows sufficient to provide a "minimum required air gap (water distribution)" as defined in ASME A 112.1.2. Where it is not possible to provide a minimum air gap (water distribution), the water outlet shall be equipped with an accessible backflow preventer complying with §609. B of this code.

2. Back-Siphonage. Potable water supply piping, water discharge outlets, backflow prevention devices or similar equipment shall not be so located as to make possible their submergence in any contaminated or polluted liquid or substance.

1. Flushometer. Flushometer valves shall be equipped with an approved vacuum breaker. The vacuum breaker shall be installed on the discharge side of the flushing valve with the critical level at least 4 inches (102 mm) above the overflow rim of the bowl. Flushometer tanks shall be provided with an approved backflow prevention device installed above the flood-level rim of the fixture.

2. Flush Tanks. Flush tanks shall be equipped with an approved ballcock. The ballcock shall be installed with the critical level of the vacuum breaker at least 1-inch (25.4 mm) above the full opening of the overflow pipe. In cases where the ballcock has no hush tube, the bottom of the water supply inlet shall be installed at least 1-inch (25.4 mm) above the full opening of the overflow pipe. A sheathed ballcock shall be installed on all gravity flush tanks in which the flush valve seat is less than 1-inch (25.4 mm) above the flood-level rim of the bowl.

3. Lawn Sprinklers and Irrigation Piping System. Lawn sprinkler systems and irrigation piping systems shall be equipped with an approved backflow preventer to protect against contamination of the potable water system. The following devices shall be acceptable.

4. Fixture Valve Outlets with Hose Attachments, Hose Bibbs and Lawn Hydrants. Fixture valve outlets with hose attachments, hose bibbs, and lawn hydrants shall comply with the following.

5. Water Supply to Steam and Hot Water Heating Boilers, Heat Exchangers, Chilled Water Systems, etc. A backflow preventer device which will automatically vent to the atmosphere shall be installed in the water supply line to all steam and hot water space heating boilers, heat exchangers, chilled water systems and similar devices being supplied from the potable water system. Such devices shall prevent back-siphonage and backflow from the heating system into the potable supply lines should the supply pressure fall below the pressure in the heating system. Such devices shall meet the requirements of ASSE 1012 or 1013 and shall bear such identification as is required by the applicable standard. See §609. F of this code for acceptable types based upon the application.

6. Connections to automatic fire sprinkler systems shall be required to meet the minimum requirements as referenced in §609. F of this code.

7. Handheld Showers and Pull -out Spout Type Faucets. Handheld showers and pull-out spout type faucets with integral backflow protection shall comply with ASME A112.18.1, CSA B125.1, or ASME A112.18.3; or, in lieu thereof, shall require a dedicated deck or wall mounted vacuum breaker.

8. Portable Cleaning Equipment. Where the portable cleaning equipment connects to the water distribution system, the water distribution system shall be protected against backflow with an air gap (water distribution), an atmospheric type vacuum breaker, a pressure type vacuum breaker or a reduced pressure principle backflow preventer. See §609. F of this code for acceptable types based upon the application.

9. Chemical Dispensers. Where chemical dispensers connect to the water distribution system, the water distribution system shall be protected against backflow with an air gap (water distribution), an atmospheric type vacuum breaker, a pressure type vacuum breaker or a reduced pressure principle backflow preventer. See §609. F of this code for acceptable types based upon the application.

10. Dental Pump Equipment. Where dental pumping equipment connects to the water distribution system, the water distribution system shall be protected against backflow with an air gap (water distribution), an atmospheric type vacuum breaker, a pressure type vacuum breaker or a reduced pressure principle backflow preventer. See §609. F of this code for acceptable types based upon the application.

1. Reduced pressure zone (RPZ) type backflow preventers, and other types of backflow preventers with atmospheric ports and/or test cocks (e.g., atmospheric type vacuum breakers, double check valve assemblies, pressure type vacuum breaker assemblies, etc.), shall not be installed below grade(G) (in vaults or pits) where the potential for a relief valve, an atmospheric port, or a test cock being submerged exists.

2. Pipe-applied atmospheric type vacuum breakers shall be installed not less than 6 inches (152 mm) above all downstream piping and not less than 6 inches (152 mm) above the flood-level rim of the fixture receptor or device served. Pipe-applied pressure type vacuum breakers shall be installed not less than 12 inches (305 mm) above all downstream piping and not less than 12 inches (305 mm) above the flood-level rim of the fixture receptor or device served. Approved deck-mounted vacuum breakers and vacuum breakers within equipment, machinery and fixtures, whether of the atmospheric or spill -proof pressure type, where the critical level is a fixed distance above the potential source of contamination, shall be installed not less than 1-inch (25.4 mm) above the flood-level rim of the fixture receptor device served or source of contamination.

3. Access, Clearance, and Platform. Backflow preventer assemblies shall be installed in an accessible location to provide for the required testing, maintenance and repair. A minimum of 1-foot of clearance shall be provided between the lowest portion of the assembly and grade(g) or platform. Elevated installations exceeding 5-feet above grade(g) shall be provided with a suitably located permanent platform capable of supporting the general tester, licensed plumber, or any other person authorized in accordance with §609. F.8 and 609.F.9 of this code to test or repair the assembly.

1. Purpose. The purpose of this Subsection is to provide for the protection of the public from the possibility of contamination or pollution by isolating such contaminants or pollutants which could backflow or back-siphon into a potable water supply; to promote the elimination or control of existing cross-connections, actual or potential, between potable water supplies and non-potable systems/sources; and to promote the maintenance of a continuing program of cross-connection control in the State of Louisiana.

2. Definitions. Definitions contained in Chapter 2 shall also apply to this Subsection except where the following special definitions shall apply.

Air Gap (Water Distribution) -in a water supply system and/or a water distribution system, the unobstructed vertical distance through the free atmosphere between the lowest opening from any pipe or faucet supplying water to a tank, plumbing fixture, or other device and the flood-level rim of the receptacle.

Atmospheric Vacuum Breaker-a device which prevents back-siphonage backflow by creating an atmospheric vent when there is either a negative pressure or sub-atmospheric pressure in a water supply system and/or water distribution system.

Backflow-the flow of water or other liquids, mixtures, or substances into the distribution pipes of a potable water supply system and/or water distribution system from any source other than its intended source. See Back Pressure Backflow and Back-Siphonage Backflow.

Back-Pressure Backflow-a condition which occurs when the downstream pressure is higher than the supply pressure causing a reversal of the normal direction of flow.

Backflow Preventer-a mechanical device which prevents backflow of contaminants and pollutants into a potable water supply or distribution system by means of positive check members in addition to atmospheric ports.

Backflow Prevention Assembly-a testable backflow preventer which comes assembled from the manufacturer as a complete unit having approved test cocks with shut off valves installed on both the inlet and outlet sides of the backflow preventer.

Backflow Prevention Device-a non-testable backflow preventer.

Back-Siphonage Backflow-a reversal of the normal direction of flow in the pipeline due to a negative pressure (vacuum) being created in the supply line with the backflow source subject to atmospheric pressure.

Barometric Loop-a fabricated piping arrangement rising at least 35 feet at its topmost point above the highest fixture it supplies. It is utilized in water supply and distribution systems to protect against back -siphonage backflow.

By-Pass-any system of piping or other arrangement whereby the water may be diverted around any part or portion of a water supply system, water distribution system or water treatment facility including, but not limited to, around an installed backflow preventer.

Commercial Dishwasher-a mechanical dishwasher that is used in other than domestic applications.

Containment-a method of backflow prevention which requires a backflow prevention device or method on the water service pipe to isolate the customer from the water main.

Contamination-the introduction into water of microorganisms, chemicals, toxic substances, wastes or wastewater that makes the water unfit for its intended use.

Cross Connection-any connection or arrangement by means of which contaminants of any kind can be caused to enter the potable water supply system or water distribution system.

Degree of Hazard-an evaluation of the potential risk to public health if the public were to be exposed to contaminated water caused by an unprotected or inadequately protected cross connection.

Double Check Valve Assembly-an assembly of 2 independently operating spring loaded check valves, with tightly closing shut off valves on each side of the check valves, plus properly located test cocks for the testing of each check valve.

Double Check Valve with Intermediate Atmospheric Vent-a device having two spring loaded check valves separated by an atmospheric vent chamber.

Dual Check Valve-two spring loaded, independently operating check valves without tightly closing shut-off valves and test cocks. Generally employed immediately downstream of the water meter. Not an approved backflow prevention device.

Fixture Isolation-a method of backflow prevention in which a backflow preventer is located to correct a cross-connection at a fixture located within the premise itself [rather than locating a backflow preventer on the water service pipe (as is done under containment)].

Hose Bibb Vacuum Breaker-a device which is permanently attached to a hose bibb and which acts as an atmospheric vacuum breaker.

Human Consumption-the use of water by humans for drinking, cooking, bathing, showering, hand washing, dishwashing, or maintaining oral hygiene.

Master Meter-a water meter serving multiple residential dwelling units or multiple commercial units. Individual units may or may not be sub-metered.

Potable Water-water having bacteriological, physical, radiological and chemical qualities that make it safe and suitable for human consumption.

Potable Water Supply-a publicly owned or privately owned water supply system which purveys potable water.

Pressure Vacuum Breaker-a device containing one or two independently operated spring loaded check valves and an independently operated spring loaded air inlet valve located on the discharge side of the check or checks. The device includes tightly closing shut-off valves on each side of the check valves and properly located test cocks for the testing of the check valve(s).

Public Water System-a particular type of water supply system intended to provide potable water to the public having at least fifteen service connections or regularly serving an average of at least twenty-five individuals daily at least sixty days out of the year.

Reduced Pressure Principle Backflow Preventer-an assembly consisting of two independently operating approved check valves with an automatically operating differential relief valve located between the two check valves, tightly closing shut-off valves on each side of the check valves plus properly located test cocks for the testing of the check valves and relief valve.

Service Connection-water service pipe.

Water Service Pipe-the pipe from the water main and/or water meter, water supply system or other approved source of water supply, to the building or structure served.

Water Supplier-a person who owns or operates a water supply system including, but not limited to, a person who owns or operates a public water system.

Water Supply System-the system of pipes or other constructed conveyances, structures and facilities through which water is obtained, treated to make it potable (if necessary) and then distributed (with or without charge) for human consumption or other use.

3. Air Gaps (Water Distribution). The provision of air gaps (water distribution) shall be required for backflow prevention in any and all cases where such a measure is the most practical that can be employed. The "minimum required air gap (water distribution)" shall be in accord with ASME A 112.1.2.1

1For informational purposes only, ASME A 112.1.2 generally requires a minimum required air gap equal to two times the effective opening (or 3 times the effective opening if affected by a nearby wall). Compliance shall be strictly determined by the provisions contained within the standard itself.

4. Responsibility of Water Suppliers. As required by LAC 51:XII.344, each water supplier shall protect the water produced and distributed by its water supply system from potential contamination by ensuring compliance with the containment practices and maintenance/field testing requirements prescribed by this Part or as otherwise directed by the state health officer.

5. Containment Practices. Backflow prevention methods or devices shall be utilized as directed by the water supplier or plumbing official to isolate specific water supply system customers from the water supply system's mains when such action is deemed necessary to protect the water supply system against potential contamination caused by backflow of water from that part of the water system owned and maintained by the customer (e.g., the piping downstream of the water meter, if provided).

6. Fixture Isolation Practices. Water supply system customers shall provide and maintain backflow prevention methods or devices as directed by the plumbing official within that part of the water system owned and maintained by the customer (e.g., the piping downstream of the water meter, if provided, or downstream from any containment device) to protect the on-site users of the water system against potential contamination due to backflow.

7. Bypasses. All bypasses shall have the same level of backflow protection as the main water supply line.

8. Installation/Repair. Backflow preventers shall be installed and/or repaired by a State Plumbing Board of Louisiana (SPBLA)-licensed plumber who holds a SPBLA water supply protection specialist endorsement on his/her plumbing license pursuant to LSA - R.S. 37:1361 et seq. and its implementing regulations (LAC 46:LV.101 et seq.); or, for those backflow preventers located on public property or otherwise under the complete control of the water supplier (e.g., water meter and the piping upstream of the water meter, if provided), by a Backflow Prevention Assembly Repairer who meets the ASSE 5130 Professional Qualification Standard or other individuals holding a backflow prevention assembly repairer certificate from a nationally recognized backflow certification organization approved by the state health officer. Backflow preventers associated with a landscape irrigation system may be installed, tested, and repaired by a Horticulture Commission of Louisiana-licensed landscape irrigation contractor who holds a SPBLA -issued special water supply protection specialist endorsement in accord with R.S. 3:3808.P.

9. Maintenance/Field Testing. Backflow prevention assemblies and methods shall be checked and field tested by a Backflow Prevention Assembly Tester who meets ASSE 5110 Professional Qualification Standard, or other individuals holding a testing certificate from a nationally recognized backflow certification organization approved by the state health officer. Testing procedures shall be in accord with the requirements of §319. F of this code.