13.35.050 Valve registration, capacity and test.
The device shall be so constructed that the bypass meter will register the water passing through it at 100 percent plus or minus two percent, up to at least the following rates of flow:
3-inch size 4 G.P.M. | 1/8 inch |
4-inch size 13 G.P.M. | 1/4 inch |
6-inch size 30 G.P.M. | 3/8 inch |
8-inch size 53 G.P.M. | 1/2 inch |
The difference in pressure between the inlet and outlet connections of the device must not at any time exceed three and one-half pounds per square inch. This maximum loss of pressure should be at or near the breaking point of the valve.
In addition to the first-mentioned test, the main line valve must be perfectly tight under a pressure of 300 pounds per square inch, in the direction opposite the normal direction of the flow, and shall also be tight against a pressure of two pounds per square inch in the normal direction of flow.
All material and workmanship used in the manufacture of these detector check valves must be of the best quality, and must be listed as inspected and approved by the Underwriters Laboratories of the National Board of Fire Underwriters. [Ord. 962 Art. IV, § 35, 1959; Code 1970 § 13.28.050; Code 1954 § 4-3.68.]