52 Pa. Code § 59.111
(a) Definitions. The following words and terms, when used in this section, have the following meanings, unless the text clearly indicates otherwise:
Adjustments—Gas used by an NGDC or city natural gas distribution operation for safe and reliable service, such as company use, calculable losses from construction, purging, storage migration, other temperature and pressure adjustments, and adjustments for heat content of natural gas.
Gas delivered—Gas provided by the distribution, transmission, storage or production/gathering facilities of an NGDC or city natural gas distribution operation, regardless of use, adjusted for temperature or pressure variations. This category includes quantities of gas consumed by an end user, exchange gas supplied to another utility, gas delivered to transportation customers or other gas delivered to a user other than the utility. When bill timing issues arise, an effort shall be made to reasonably estimate consumption.
Gas received—Gas that is supplied to the distribution, transmission, storage or production/gathering facilities of an NGDC or city natural gas distribution operation, regardless of use, adjusted for temperature or pressure variations. This category includes gas for sales, storage, transportation quantities, exchange gas received or other quantity of gas that otherwise enters the utility’s facilities.
NGDC—Natural gas distribution company.
UFG—Unaccounted-for-gas—The difference between the total gas available from all sources and the total gas accounted for as sales, net interchange and company use. This difference includes leakage or other actual losses, discrepancies due to meter inaccuracies, variations of temperatures or pressures, or both, and other variants, particularly billing lag.
(b) Calculation.
(c) Metrics for distribution system losses.
(1) Each NGDC and city natural gas distribution operation shall, at a minimum, reduce distribution system loss performance in accordance with the metrics in the following table, beginning with its first subsequent Purchased Gas Cost (PGC) or Gas Cost Rate (GCR) filing after August 11, 2014. The metric starts with 5% in the first year and decreases by 0.5% every year in the subsequent years until it reaches 3% as shown in the following table:
| Year | Percent UFG | |
| 1 | 5.00% | |
| 2 | 4.50% | |
| 3 | 4.00% | |
| 4 | 3.50% | |
| 5 | 3.00% |
The provisions of this § 59.111 issued under 66 Pa.C.S. § § 501, 504, 523, 1301, 1501 and 1504.
The provisions of this § 59.111 adopted August 9, 2013, effective August 10, 2013, 43 Pa.B. 4586.