Title 13 PUBLIC SERVICES

Chapter 13.72 BACKFLOW AND CROSS-CONNECTIONS


13.72.410 Penalties.

The owner or authorized agent of the owner responsible for the maintenance of the plumbing systems in the building who knowingly permits a violation to remain uncorrected after the expiration of time set by the board of trustees shall, upon conviction thereof by the court, be required to pay a fine of not less than twenty-five dollars nor more than five hundred dollars for each violation. Each day of failure to comply with the requirements of this chapter, after the specified time provided under Section 13.72.400, shall constitute a separate violation. (Ord. 1987-9 § 5.2, 1987)

Table 13.72.070(1)

Minimum Air Gaps for Generally Used Plumbing Fixtures

Fixture
Minimum Air Gap
When not affected by near wall1 (inches)
When affected by near wall2 (inches)



Lavatories and other fixtures with effective openings not greater than one-half inch in diameter
1.0
1.50



Sink, laundry trays, goose-neck bath faucets other fixtures with effective openings not greater than three-quarter-inch in diameter
1.5
2.25



Over-rim bath fillers and other fixtures with effective openings not greater than one inch in diameter
2.0
3.0



Drinking water fountains: single orifice 7/16 inch in diameter or multiple orifices having total area of 0.150 sq. in. (area of circle 7/16 inch in diameter)
1.0
1.50



Effective openings greater than one inch
(3)
(4)

1. Side walls, ribs or similar obstructions do not affect air gaps when spaced from inside edge of spout a distance greater than three times the diameter of the effective opening for a single wall, or a distance greater than four times the effective opening for two intersecting walls.
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 when spaced closer to the nearest inside edge of spout opening than specified in Note 1 above. The effect of three or more such vertical walls or ribs has not been determined. In such cases, the air gap shall be measured from the top of the wall.
3. Two times the diameter of the effective opening.
4. Three times the diameter of the effective opening.

Table 13.72.070(2)

Sizes of Overflow Pipes for Water Supply Tanks

Maximum Capacity of Water Supply Line to Tank
Diameter of Overflow Pipe (inches ID)
Maximum Capacity of Water Supply Line to Tank
Diameter of Overflow Pipe (inches ID)




0--50 gpm
2
400--700 gpm
5
50--150 gpm
2 1/2
700--1,000 gpm
6
100--200 gpm
3
Over 1,000 gpm
8
200--400 gpm
4


Table 13.72.070(3)

Cross-Connections Where Protective Devices are
Required and Critical Level (C-L) Settings for Vacuum Breakers*

Fixture or Equipment
Method of Installation


Aspirators and ejectors
C-L at least 6 in. above flood level of receptacle served.


Dental Units
On models without built-in vacuum breakers--C-L at least 6 in. above flood level rim of bowl.


Dishwashing machines
C-L at least 6 in. above flood level of machine. Install on both hot and cold water supply lines.


Flushometers (closet and urinal)
C-L at least 6 in. above top of fixture supplied.


Garbage can cleaning machine
C-L at least 6 in. above flood level of machine. Install on both hot and cold water supply lines.


Hose outlets
C-L at least 6 in. above highest point on hose line.


Laundry machines
C-L at least 6 in. above flood level of machine. Install on both hot and cold water supply lines.


Lawn sprinklers
C-L at least 12 in. above highest sprinkler or discharge outlet.

Table 13.72.070(3) (Continued)

Fixture or Equipment
Method of Installation


Steam tables
C-L at least 6 in. above flood level.


Tanks and vats
C-L at least 6 in. above flood level rim or line.


Trough urinals
C-L at least 30 in. above perforated flush pipe.


Flush tanks
Equip with approved ball-cock. Where ball cocks touch tank water equip with vacuum breaker at least 1 in. above overflow outlets. Where ball-cock does not touch tank water, install ball cock outlet at least 1 in. above overflow outlet or provide vacuum breaker as specified above.


Hose bibbs (where aspirators or ejectors could be connected)
C-L at least 6 in. above flood level or receptacle served.

* "Critical-Level (C-L)" is defined as the level to which the vacuum breaker may be submerged before backflow will occur. Where the C-L is not shown on the preventer, the bottom of the device shall be taken as the C-L.

Table 13.72.070(4)

Partial List of Cross-Connections
Which May be Subject to Back Pressure

Chemical line
Pumps
Dock water outlets
Steam lines
Individual water supplies
Swimming pools
Industrial process water lines
Tanks and vats--bottom inlets
Pressure tanks
Hose bibbs