100. REQUIREMENT Each utility whose gas output exceeds 10,000 cubic feet per year shall provide and maintain a calorimeter of a type approved by the Commission and all necessary accessories therefor, except when the utility purchases its entire requirements for natural gas and has access to sufficient records of tests made by its supplier or has sufficient tests by an accredited laboratory as provided for in Rule 54.105.105. ACCURACY The accuracy of all calorimeters as well as the method of making heating value tests, shall be subject to the approval of the Commission or its representatives.110. STANDARD FORM RECORDS Each utility making heating value determination shall adopt, subject to the approval of the Commission, a standard form for recording the results of each such test. Each determination of the heating value shall be recorded originally upon the form adopted for that purpose and such forms shall be retained as a record of the utility.