815 KAR 20:120. Water supply and distribution.

 

      RELATES TO: KRS 318.010, 318.130, 318.150, 318.165, 318.200

      STATUTORY AUTHORITY: KRS 198B.040(10), 318.130

      NECESSITY, FUNCTION, AND CONFORMITY: KRS 318.130 requires the office, after review by the State Plumbing Code Committee, to promulgate an administrative regulation establishing the Kentucky State Plumbing Code regulating plumbing, including the methods and materials that may be used in Kentucky. This administrative regulation establishes the types of piping and pipe sizes required for a potable water supply system and the methods to be used to protect and control the water supply system and requires the manufacturer's specification number of the material accepted in those installations to be identified and published.

 

      Section 1. Definitions. (1) "ASSE" means the American Society of Sanitary Engineers.

      (2) "ASTM" means the American Society for Testing Materials.

      (3) "Critical level" or "CL" means the level to which the vacuum breaker may be submerged before backflow will occur, and if the CL marking is not shown on the vacuum breaker, the bottom of the device shall be taken as the CL.

      (4) "DWV" means drain, waste and vent piping.

      (5) "NSF" means the National Sanitation Foundation.

      (6) "SDR" means standard dimensional ratio.

 

      Section 2. Quality. (1) The bacteriological and chemical quality of the water supply shall comply with the administrative regulations of the office and other governing authorities. Toxic material shall be kept out of a potable water system.

      (a) The pipe conveying, and each surface in contact with, potable water shall be constructed of nontoxic material.

      (b) A chemical or other substance that could produce either a toxic condition, taste, odor, or discoloration in a potable water system shall not be introduced into, or used in, the system.

      (c) The interior surface of a potable water tank shall not be lined, painted, or repaired with a material that will affect the taste, odor, color, or potability of the water supply if the tank is placed in, or returned to, service.

      (2) Potable water shall be accessible to a plumbing fixture that supplies water for drinking, bathing, culinary use or the processing of a medicinal, pharmaceutical, or food product.

      (3) The potable water supply system shall be designed, installed, and maintained to prevent contamination from a nonpotable liquid, solid, or gas being introduced into the potable water supply through a cross connection or other piping connection to the system.

      (4) A cross connection shall be prohibited unless:

      (a) The connection meets the other requirements established in this administrative regulation; and

      (b) A suitable protective device is installed.

      (5) A cross connection between a private water supply and a public water supply shall not be made.

      (6) Closed water systems, protection from excess pressure.

      (a) If a single check valve is installed in a water system, a thermal expansion tank sized in accordance with manufacturer’s instructions shall be installed in the cold water supply located near the water heater.

      (b) If a backflow preventer is installed in a water system, a properly sized thermal expansion tank or other pressure relief device listed in 815 KAR 20:020 shall be installed in the water distribution system.

      (c) If a pressure reducing valve not equipped with a bypass is installed in the cold water supply line to a water heater, a thermal expansion tank shall be installed in the cold water line near the water heater.

      (7) Backflow and back siphonage protection. Protection against backflow shall be provided as required in paragraphs (a) through (l) of this subsection in order of degree of protection provided. Backflow shall include both back pressure and back siphonage.

      (a) An air gap shall provide the best level of protection in all backflow situations. The minimum required air gap shall be determined as follows:

      1. How measured. The minimum required air gap shall be measured vertically from the lowest end of a potable water outlet to the flood rim or line of the fixture or receptacle into which it discharges.

      2. Size. The minimum required air gap shall be:

      a. Twice the effective opening of a potable water outlet; or

      b. If the outlet is a distance less than three (3) times the effective opening away from a wall or similar vertical surface, three (3) times the effective opening of the outlet.

      3. The minimum required air gap shall not be less than shown in the following table - Minimum Air Gaps for Plumbing Fixtures.

MINIMUM AIR GAPS FOR PLUMBING FIXTURES
Fixture	Minimum Air Gap
	When not affected by near wall (inches)	When affected by near wall (inches)
Lavatories and other fixtures with effective opening not greater than 1/2 inch diameter	1	1 1/2
Sink, laundry trays, gooseneck bath faucets and other fixtures with effective openings not greater than 3/4 inch diameter	1 1/2	2 1/4
Over rim bath fillers and other fixtures with effective openings not greater than 1 inch diameter	2	3
Drinking water fountains - single orifice not greater than 7/16 (0.437) inch diameter or multiple orifices having total area of 0.150 square inches (area of circle 7/16 inch diameter)	1	1 1/2
Effective openings greater than 1 inch	2 x diameter of effective opening	3 x diameter of effective opening

      NOTE 1. Side walls, ribs, or similar obstructions do not affect air gaps if spaced from the inside edge of the spout opening a distance greater than three (3) times the diameter of the effective opening for a single wall, or a distance greater than four (4) times the diameter of the effective opening for two (2) intersecting walls.

      NOTE 2. Vertical walls, ribs, or similar obstructions extending from the water surface to or above the horizontal plane of the spout opening require a greater air gap if spaced closer to the nearest inside edge of spout opening than specified in NOTE 1 above. The effect of three (3) or more vertical walls or ribs has not been determined. In this case, the air gap shall be measured from the top of the wall.

      (b) A reduced pressure principle back pressure backflow preventer. A reduced pressure principle back pressure backflow preventer shall provide the best mechanical protection against backflow available and shall be considered equivalent to an air gap.

      (c) Double check valve assembly: applicable to low level of hazard back pressure backflow conditions. This device shall be a manufactured assembly consisting of two (2) independently acting check valves and including a shutoff valve at each end, and petcock and test gauge for testing the watertightness of each check valve.

      (d) Pressure type vacuum breaker: applicable to back siphonage conditions.

      (e) Atmospheric type vacuum breaker: applicable to back siphonage conditions. If applicable, an atmospheric type vacuum breaker shall be installed after the last cutoff valve on the water line. This device may operate under normal atmospheric pressure if the critical level (CL) is installed at the required height in accordance with the table in this paragraph:

CRITICAL LEVEL (CL) SETTINGS FOR ATMOSPHERIC TYPE VACUUM BREAKERS
Fixture or Equipment	Method of Installation
Aspirators, ejectors, and showers	CL at least 6 in. above flood level of receptacle
Bidets	CL at least 6 in. above flood level of receptacle
Cup beverage vending machines	CL at least 12 in. above flood level of machine
On models without built-in vacuum breakers:
Dental units	CL at least 6 in. above flood level rim of bowl.
Dishwashing machines	CL at least 6 in. above flood level of machine
Flushometers (closet & urinal)	CL at least 6 in. above top of fixture supplied
Garbage can cleaning machines	CL at least 6 in. above flood level of machine
Hose bibs (sinks or receptacles)	CL at least 6 in. above flood level of receptacle served
Hose outlets	CL at least 6 in. above highest point on hose line
Laundry machines	CL at least 6 in. above flood level of machine
Lawn sprinklers	CL at least 12 in. above highest sprinkler or discharge outlet
Steam tables	CL at least 12 in. above flood level
Tanks & vats	CL at least 6 in. above flood level rim or line

      (f) Barometric loop: applicable to back siphonage conditions. The use of a barometric loop shall not be acceptable as the primary back siphonage preventer.

      (g) Location of backflow and back siphonage preventers. A backflow and back siphonage preventer shall be in an accessible location, preferably in the same room as the fixture or connection it protects. A device may be installed in a utility or service space. A device or air gap shall not be installed in a location subject to flooding or freezing.

      (h) Inspection of devices. A periodic inspection shall be made of each backflow and back siphonage preventer to determine if it is in proper working condition. A reduced pressure principle back pressure backflow preventer shall be tested on at least an annual basis. Records shall be kept on each inspection.

      (i) Approval of devices. Before a device for the prevention of backflow or back siphonage is installed, it shall be identified as meeting the applicable specifications as listed in the application chart included in paragraph (l) of this subsection. A device installed in a building potable water supply distribution system for protection against backflow shall be maintained in good working condition by the person responsible for the maintenance of the system.

      (j) Protection of potable water system. A potable water opening, outlet, or connection, except one (1) that serves a residential unit, shall be protected against backflow in accordance with paragraphs (a) through (l) of this subsection.

      (k) Degree of hazard. The protection required at an outlet or connection shall be determined based on the degree of hazard posed by that outlet or connection as follows:

      1. Severe hazard, if there is potential for contamination by a toxic substance or disease-causing organism;

      2. Moderate hazard, if there is potential for contamination by a nontoxic but objectionable substance; or

      3. Minor hazard, if there is potential for contamination by a generally nontoxic, nonobjectionable substance, but which may cause the consumer to question the quality of water.

      (l) Minimum acceptable protection. An opening or outlet shall be protected by an air gap between the opening and flood level rim if possible. The acceptable protection for various types of outlets or connections shall be as shown in the tables in this paragraph:

 

APPLICATION TABLE
TYPE AND PRESSURE	DESCRIPTION	INSTALLED AT	EXAMPLES OF INSTALLATIONS	APPLICABLE SPECIFICATIONS
Reduced pressure principle backflow preventer for high hazard cross connections	Two independent check valves with intermediate relief valve. Supplied with shut-off valves and ball-type test cocks.	All cross connections subject to backpressure or back siphonage if there is a high potential health hazard from contamination. Continuous pressure.	Main supply lines, commercial boilers, cooling towers, hospital equipment, processing tanks, laboratory equipment, waste digesters, car wash, sewage treatment, lawn sprinklers	ASSE No. 1013 AWWA C506 FCCCHR of U.S.C. CSA B.64.4 Sizes 3/4" - 10"
(A) Double check valve assembly for low hazard cross connections	Two independent check valves. Supplied with shutoff valves and ball type test cocks.	All cross connections subject to back pressure if there is a low potential health hazard or nuisance. Continuous pressure.	Main supply lines, food cookers, tanks and vats, commercial pools	NONTOXIC	ASSE No. 1015 AWWA C506 FCCCHR of U.S.C. CSA B.64.5 Sizes 3/4" - 10"
(b) Dual check valve backflow preventer for low hazard applications	Two independent check valves. Checks are re-movable for testing	Cross connections if there is a low potential health hazard and moderate flow requirements.	Post ground hydrants		ASSE No. 1024 Sizes 3/4" & 1"
(A) Backflow preventer with intermediate atmospheric vent for moderate hazard cross connections in small pipe sizes	Two independent check valves with intermediate vacuum breaker and relief valve.	Cross connections subject to back pressure or back siphonage if there is a moderate health hazard. Continuous pressure.	Boilers (small), cooling towers (small), dairy equipment residential	ASSE No. 1012 CSA B.64.3 Sizes 1/2" & 3/4"
(B) Backflow preventer for carbonated beverage machine	Two independent check valves with a vent to atmosphere	On potable water distribution lines serving beverage-dispensing equipment to prevent backflow of carbon dioxide gas and carbonated water into the water supply system.	Postmix carbonated beverage machine	ASSE 1022
(C) Laboratory faucet and double check valve with intermediate vacuum breaker in small pipe sizes for moderate to low hazard	Two independent check valves with intermediate vacuum breaker and relief vent.	Cross connection subject to back pressure or back siphonage if there is a moderate to low health hazard.	Laboratory faucets and pipe lines, barber shop and beauty parlor sinks	ASSE No. 1035 (N-LF9)
(A) Atmospheric vacuum breakers for moderate to high hazard cross connections	Single float and disc with large atmospheric port.	Cross connections not subject to backpressure or continuous pressure. Install at least 6" above fixture rim. Protection against back siphonage only.	Process tanks, dishwashers, soap dispensers, washing machines	ASSE No. 1001 ANSI.A112.1.1 CSA B.64.1.1 FCCCHR of U.S.C. Sizes 1/4" - 3"
(B) Antisiphon pressure breakers for moderate to high hazard cross connections	Spring loaded single float and disc with independent 1st check. Supplied with shutoff valves and ball type test cocks.	This valve is designed for installation in a continuous pressure potable water supply system 12" above the overflow level of the system being supplied. Protection against back siphonage only.	Laboratory equipment, cooling towers, comm. Laundry machines, swimming pools, commercial plating tanks, lg. Toilet total & urinal facilities, degreasers, photo tanks, livestock water systems, lawn sprinklers	ASSE No. 1020 CSA B.64.1.2 FCCCHR of U.S.C. Sizes 1/2" - 2"
(C) Hose connection vacuum breakers for residential and industrial hose sup-ply outlets	Single check with atmospheric vacuum breaker vent.	Install directly on hose bibs, service sinks and wall hydrants. Not for continuous pressure.	Hose bibs, service sinks, hydrants	ASSE No. 1011 CSA B.64.2 Size 3/4" Hose

 

 

CROSS CONNECTIONS, DEGREE OF HAZARD AND ACCEPTABLE PROTECTION FOR VARIOUS PLUMBING OUTLETS AND CONNECTIONS
	Degree of Hazard					Acceptable Protection
Type of Connection							Backflow		Backsiphonage
	Severe	Moderate	Minor	Air Gap	Reduced Pressure Device		Double Check Valve Assembly	Pressure Type Vacuum Breaker		Atmospheric Type Vacuum Breaker
I. Connections subject to back pressure from:
A. Pumps, tanks, and lines handling:
1. Toxic substance	X			X	X
2. Nontoxic substance		X		X	X		X
B. Boilers
1. With chemical additives	X			X	X
2. Without chemical additives		X		X	X		X
C. Gravity due to obvious site conditions subject to:
1. Contamination by toxic substances	X			X	X
2. Contamination by nontoxic substances		X		X	X		X
II. Water outlets and connections not subject to back pressure:
A. Connection to sewer or sewage pump	X			X
B. Outlet to receptacles containing toxic substances	X			X	X			X		X
C. Outlet to receptacles containing nontoxic substances		X		X	X		X	X		X
D. Outlet into domestic water tanks			X	EACH CASE TREATED SEPARATELY
E. Flush valve toilets	X			X	X			X		X
F. Flush valve urinals		X		X	X			X		X
G. Outlets with hose attachments subject to contamination from:
1. Toxic substance	X			X	X			X		X
2. Nontoxic substance		X		X	X