W. Va. Code § 19-11A-8: Approved sampling and testing methods.

(a) All sampling and testing methods shall be those set forth in the fifteenth edition of and supplement to the Official Methods of Analysis of the Association of Official Analytical Chemists, published by the Association of Official Analytical Chemists; or the fifteenth edition of the Standard Methods for the Examination of Dairy Products, published by the American Public Health Association, Inc.; or methods approved by the commissioner.

(b) The Babcock method or other methods approved by the commissioner for determining the milk fat content of dairy products shall be used as the reference method to establish and maintain the calibration of automated testing instruments.