PSC 134.21(3)(3) The monthly average heating value of the gases as delivered to the customers in any service area shall not be less than the heating value standard on file with this commission and the heating value at any time at constant specific gravity shall not be more than 5% above or 4% below this standard. At constant heating value, the specific gravity of the gas shall not vary more than 10% from the standards filed with the commission. If the heating value is varied by a greater amount than specified, the specific gravity shall be varied in such a way that the gas will operate satisfactorily in the customer’s utilization equipment. Customers using processes that may be affected by a change in the chemical composition of the gas shall be notified of changes. Agreements with such customers shall specify the allowable variation in composition.

PSC 134.21(4)(4) For required periodic heating value tests see s. PSC 134.25. The specific gravity of the gas shall be determined at least once each month when there is no change in the type or sources of gas and when there is a change in the type of gas. Whenever emergency or peak shaving plants are ran or when mixed gases are used, daily determinations of specific gravity shall be made.

PSC 134.22(1)(1) In no case shall gas contain more than 30 grains of sulphur per 100 standard cubic feet, 5 grains of ammonia per 100 standard cubic feet, nor more than 0.1 grain of hydrogen sulphide per 100 standard cubic feet. (Exception. If the gas is not to be placed in pipe or bottle type holders the hydrogen sulphide content may be 0.3 grains per 100 standard cubic feet.)

PSC 134.22(2)(2) Utilities supplying gas containing coal or water gas shall make quantitative determinations of total sulphur at least once every 6 months and qualitative hydrogen sulphide tests at intervals of 1 hour to 2 weeks depending upon the probability of this impurity being found.

PSC 134.22(3)(3) Utilities supplying liquefied petroleum gas, or liquefied petroleum air mixtures, or natural gas shall test the gas periodically for impurities or periodically obtain data concerning impurities from sources they believe the commission can accept as reliable.

PSC 134.23(1)(1) Every utility supplying gas shall file with the commission a standard service pressure by service areas. The service pressure shall be of such a value that the maximum pressure at any outlet as specified below shall not be greater than 12 inches of water column except for customers utilizing high-pressure service.

PSC 134.23(2)(2) For customers receiving standard service pressure, the gas pressure at the outlet of the utility’s service meters shall meet the following requirements:

PSC 134.23(2)(a)(a) At no outlet in the service area shall it ever be greater than one and one-fourth of the standard service pressure nor greater than 12 inches of water nor ever be less than one-half of the standard service pressure nor less than 4 inches of water.

PSC 134.23(3)(3) For customers utilizing gas at high pressure, a service pressure shall be agreed upon by the utility and the customer, and the maximum pressure variation shall not exceed 15% of the agreed pressure unless the commission shall authorize a greater variation.

PSC 134.23(4)(4) No utility shall furnish gas to any customer at pressures higher than its filed standard service pressure until it has filed with the commission acceptable service rules governing high-pressure service to customers desiring to utilize gas at pressures higher than standard service pressure. Such service rules shall provide that the utility will make high-pressure service available to its customers upon request whenever high pressure gas is available at the customer’s premises or may be made available in accordance with the utility’s filed extension rules, and when such high pressure is required for proper operation of the customer’s present or proposed utilization equipment.

PSC 134.25(1)(1) Unless specifically directed otherwise a calorimeter shall be maintained at each gas producing or mixing plant whether the plant is in continuous operation or used only for standby or peak shaving purposes. The calorimeter shall be used to check the operation of the plant and shall measure the heating value of the gas going to the gas lines.

PSC 134.25(2)(2) Unless specifically directed otherwise calorimeters shall be maintained in operation in locations where the heating value of the gas can be measured from each different supplier.

PSC 134.25(3)(3) Unless specifically directed otherwise a calorimeter shall be maintained and used to measure the heating value of the gas actually sold to customers in those cases where mixed gases are used.

PSC 134.25(4)(4) Tests of heating value of the gas shall be made daily whenever gas is supplied at the calorimeter location unless specifically directed otherwise by the commission. The original records of the tests shall be dated, labeled and kept on file for 6 years. A copy of the daily average heating value of gas sold to customers shall be sent to the commission each calendar month.

PSC 134.25(5)(5) The calorimeter equipment shall be maintained so as to give results within + or - 1%. Recording calorimeters used to test or control the production or mixing of gas or measure the heating value of purchased gas when therm rates are not applicable shall be tested with a gas of known heating value at least 3 times a year or when the accuracy is in question. Recording calorimeters used only with standby or peak shaving production plants shall be tested with a gas of known heating value at least 2 times a year. Non-recording calorimeter equipment such as the Junkers shall be tested with a gas of known heating value at least once a year or tested against another calorimeter of known accuracy at least once a year.

PSC 134.251(1)(1) In the application of gas rates based on the therm, a recording calorimeter shall be used to determine the heating value of the gas being distributed to utility customers. These calorimeters will be located as set forth in s. PSC 134.25 (2) and (3). They shall have such accuracy characteristics as to be able to measure the heating value of the gas to within + or -2 B.t.u., shall be able to reproduce these readings to within +or - 2 B.t.u., and shall be able to hold their accuracy over an extended period of time. The instruments shall be installed in accordance with the manufacturer’s recommendations.

PSC 134.251(2)(2) Each utility selling gas shall file with the commission a complete installation report stating the following information: location of calorimeter, kind of gas tested, type of scale, uniform or split scale range, date installed, publication number of manufacturer’s applicable book of instructions, outline of the building, the location of the calorimeter or calorimeters within the building, the size, length, gas pressure, and general route of the gas sample pipe from the supply main to each calorimeter and location of all secondary equipment necessary for the operation of the recording calorimeter.