1. (1) Where a company purchases or produces gas at one or more locations, testing stations shall be provided, maintained and operated by said company, with one testing station for each separate ultimate source of gas, located between the location of conditioning of said gas and the point of mixture of the gas with gas from any other source. All of the tests required herein shall apply to said testing stations.

2. (2) Where a company has two or more sources of gas supplying one distribution system, said company may be required to provide and maintain such addtional testing stations on its distribution system as may be necessary to enable this commission's staff to verify the quality of the mixture of gases being delivered to consumers' premises.

   (b) Joint testing stations.

3. (1) Where a company purchases gas, having a common ultimate source, at one or more locations or where two or more companies obtain their gas supply from one or more common ultimate sources, said companies may provide, maintain and operate joint testing stations, with one such testing station for each separate ultimate source of gas, located prior to the point of mixture of the gas with gas from any other source. All of the tests required herein shall apply to said testing stations.

4. (2) One or more companies may designate one testing station for each separate ultimate source of gas, provided, maintained and operated by the transmission corporation from which said companies purchase their gas, as a testing station meeting the provisions herein, provided that the gas tested by said testing station is continuously representative of that delivered to said companies, that said testing station is located within the State of New York or 40 miles thereof and that said companies shall assure this commission that said testing station continuously meets the provisions of the rules and regulations herein. All of the tests required herein shall apply to such testing stations.

   (c) Underground storage fields.

   Where a company obtains part of its gas supply from an underground storage field in which the chemical composition of the gas may be so altered as to depart from the standards established herein, the company shall take such remedial measures as may be necessary and shall provide, maintain and operate a testing station for making tests appropriate for the determination of the compliance of said gas with the provisions of the rules and regulations herein.

   (d) Small districts.

5. (1) Where a company distributes manufactured gas to 100 or less consumers or natural and/or mixed gas to 1,000 or less consumers, said mixed gas being composed of not less than 70 per cent natural gas as gaged by its thermal content on the basis of the annual gas send-out to the consumers of said gas, said company need not provide the testing stations required herein by subdivisions (a) through (d) of section 229.50.
6. (2) Where natural gas produced in the State of New York, representing less than 10 percent of the thermal content of the annual gas send-out to the consumers of said gas, feeds into a company's general transmission and distribution system at various isolated locations, said company need not provide a testing station therefor.
7. (3) Any company exempted by this section from providing a testing station in any district shall provide and maintain suitable sampling facilities to enable the staff of this commission to obtain samples of gas from the system and determine the pressure in said system.

Within 30 days of the effective date hereof, each company shall advise this commission, by a letter signed by a responsible official of the company, of the location of each of the testing stations to be provided, maintained and operated by the company and the source of the gas that each of said testing stations purports to test. If, at any time subsequent to said filing with this commission, a company obtains additional or new sources of gas, said company shall amend its filing at least 90 days prior to the effective date of said change, by a letter signed by a responsible official of the company, to advise this commission of the additional or new sources and the testing stations to be provided, maintained and operated for testing the gas to be obtained therefrom. All testing stations shall meet the following requirements:

(a) Single company testing stations.