(a) Excess flow valves (EFVs) to be used on single residence service lines that operate continuously throughout the year at a pressure not less than 10 PSIG (69 kPa) must be manufactured and tested by the manufacturer according to an industry specification, or the manufacturer's written specification, to ensure that each valve will:
(1) function properly up to the maximum operating pressure at which the valve is rated;
(2) function properly at all temperatures reasonably expected in the operating environment of the service line;
(3) at 10 psig (69 kPa) close at, or not more than 50 percent above, the rated closure flow rate specified by the manufacturer and upon closure, reduce the gas flow to the level indicated:
(i) for an excess flow valve designed to allow pressure to equalize across the valve, no more than five percent of the manufacturer's specified closure flow rate, up to a maximum of 20 cubic feet (0.566 cubic meters) per hour; or
(ii) for an excess flow valve designed to prevent equalization of pressure across the valve, no more than 0.4 cubic foot (0.011 cubic meters) per hour; and
(4) not close when the pressure is less than the manufacturer's minimum specified operating pressure and the flow rate is below the manufacturer's minimum specified closure flow rate.
(b) An excess flow valve must meet the applicable requirements of this Part regarding materials and design of pipeline components.
(c) An operator must mark or otherwise identify the presence of an excess flow valve in a service line.
(d) An operator shall locate an excess flow valve as near as practical to the fitting connecting the service line to its source of gas supply.
(e) An operator should not install an excess flow valve on a service line where the operator has prior experience with contaminants in the gas stream, where these contaminants could be expected to cause the excess flow valve to malfunction or where the excess flow valve would interfere with necessary operation and maintenance activities on the service, such as blowing liquids from the line.