Current through Register Vol. 54, No. 45, November 9, 2024
Section 59.30 - Heating value and purity of gas(a)Testing apparatus. The accuracy of testing apparatus, as well as the method of making heating-value tests, shall be subject to the approval of the Commission.(b)Tests. Each public utility shall make or obtain the determinations as may be necessary to ascertain the heating value of the gas introduced into its distribution system and shall maintain an average heating value not less than the minimum authorized. If compression, processing or other factors tend to affect the heat content of all or any portion of its gas, determinations of heating value shall be made of gas drawn from different parts of the distribution system at points remote from the point where the gas enters the distribution system, with the frequency and in the manner as may be necessary to assure compliance with this section.(c)Records of tests. Each public utility shall adopt a standard printed form for recording the results of heating value tests. Each determination of heating value shall be recorded originally upon the form adopted for that purpose. If heating value is determined by an approved type of recording calorimeter, the charts removed from a calorimeter shall be sufficient to comply with the requirements of this section. If manufactured or mixed gas is served, the average heating value determined by these tests shall be recorded.(d)Heating value. The heating value of gas shall be as follows: (1)Natural gas. If a public utility supplies natural gas, its heating value may not fall below 950 Btu total heating value per cubic foot, under standard conditions of temperature and pressure.(2)Manufactured or mixed gas. Manufactured or mixed gas shall conform with all of the following:(i) If a public utility supplies manufactured or mixed gas, its heating value shall have a monthly average of not less than 520 Btu total heating value per cubic foot under standard conditions of temperature and pressure. The minimum heating value of manufactured gas shall never fall below 500 Btu.(ii) To obtain the heating value of gas, the results of the tests of heating value made under standard practice on each day during the calendar month shall be averaged, and the average of the daily averages shall be taken as the monthly average.(iii) Each public utility serving manufactured or mixed gas shall provide and maintain a calorimeter with necessary accessories of an approved type for the regular determination of the heating value of the gas sold, unless other provision is made with the approval of the Commission.(iv) The calorimeter required for measuring manufactured or mixed gas shall be installed in a laboratory or other building so located as to insure that thoroughly mixed, stabilized and representative samples of the gas delivered to customers are used for the tests.(v) Each public utility serving manufactured or mixed gas shall determine the heating value of the gas distributed to its customers daily or more frequently if necessary, or if required by the Commission.(e)Purity of gas. The purity of gas distributed in this Commonwealth shall conform with the following:(1) Gas shall be substantially free from dangerous or objectionable quantities of impurities such as hydrogen sulphide, nitrogen or other combustible or noncombustible constituents which, if the gas is completely burned, yield noxious or toxic products of combustion.(2) Hydrogen sulphide in the gas shall be considered negligible if a strip of white filter paper, moistened with a solution containing 5.0% by weight of lead acetate, is not distinctly darker than a second paper freshly moistened with the same solution, after the first paper has been exposed for one minute in an apparatus of approved form, through which the gas is flowing at the rate of approximately 5 cubic feet per hour, the gas not impinging directly from the jet upon the test paper.(3) No gas sold shall contain more than 30 grains total of sulphur per 100 cubic feet and not more than five grains of ammonia per 100 cubic feet.