C703-79: AWWA Standard for Cold-Water Meters--Fire Service Type (PDF)

This standard covers the various types and classes of cold-water fire service type meters in sizes 3 in. (75 mm) through 10 in. (250 mm) and the materials and workmanship employed in their fabrication. Fire service meters shall consist of a combination of a main line meter of the proportional type, having an unobstructed passageway of essentially full pipe size, for measuring high rates of flow and a bypass meter of appropriate size for measuring low rates of flow. The meter shall have an automatic valve mechanism for diverting low rates of flow through the bypass meter. Included are sections on the following: general information, references, affidavit of compliance, basis for rejection, choice of materials, main castings, register box rings and covers, measuring cages or chambers, measuring turbines and discs, disc and turbine spindles, intermediate gear trains, external fasteners, automatic valves, bypass check valve, general design characteristics of size, capacity, length, pressure requirement, interior parts, registration accuracy, markings, external case screws, bolts, nuts, and washers, main case connections, companion flanges, registers and register boxes, intermediate gear trains, measuring chambers or cages, turbines and discs, magnetically coupled or direct drives, automatic valves, bypass meter, strainers, and seal wire holes. The appendix contains information on units of measurement, register types, tests, testing equipment, under and over registration, periodic tests, and meter storage.