In determining the value of milk, cream, or other dairy products by the use of the Babcock test, it shall be unlawful to give any false reading or in any way manipulate the test so as to give a higher or lower percent of butterfat than the milk, cream, or other dairy products actually contain, or to cause any inaccuracy in reading the percent of butterfat by securing from any quantity of milk, cream, or other dairy products to be tested an inaccurate sample for the test. None other than the Babcock method, or such method of testing as may be approved by the Commissioner, may be employed when testing milk or cream, the test of which is to be used as a basis for making payment for the milk or cream thus tested. None other than the torsion balanced scales, or such scales as may be approved by the Commissioner, may be used when weighing cream for testing, when the tests are to be used as a basis for making payment for cream. It shall be unlawful to use adjustable scale weights in determining the weight of cream used in the Babcock test. Only such centrifuge shall be used as shall meet the approval of the Commissioner. Specifications for apparatus and chemicals and directions for testing milk and cream must conform to Standard_Methods_for_the Examination_of_Dairy_Products, with such additions as shall be deemed advisable by the Commissioner to make them conform to this article. All test tubes, bottles, pipettes, burettes, or instruments used in connection with testing or determining the value of milk, cream, or other dairy products by the use of the Babcock test must be United States government standard and shall be approved by the Commissioner. All milk and cream tests shall be maintained at a temperature of 135 to 140 degrees Fahrenheit for at least three minutes before the reading of the percent of butterfat shall be made and recorded. In reading cream tests, glymol or its equivalent must be used, and the samples under test must be held for three minutes in a water bath extending up as high on the graduated neck as the sample itself does.