31 Pa. Stat. § 700j-602
It shall be unlawful for any milk dealer to buy or receive milk from producers, or to sell or deliver milk to stores or consumers, on the basis of, or with reference to, the amount of butterfat or appropriate milk components contained in such milk, unless the butterfat or component tests thereof is conducted by a tester certified by the board.
The certified tester shall keep an accurate record of all tests made, and copies of such record shall be kept for a period of two (2) years by him and by the milk dealer.
Any person who, upon the effective date of this act, is the holder of a certificate of proficiency for milk testing issued after examination conducted by the Pennsylvania Department of Agriculture, shall, upon application to the board, on a form prescribed by the board, furnishing information including that pertaining to good character and to the apparatus and methods used in testing, be issued a certificate and be designated therein as a certified tester.
Any person who is not the holder of such certificate of proficiency upon the effective date of this act, shall, prior to applying for a tester's certificate, apply to the board for a certificate of proficiency. Such application shall be accompanied by a fee of five dollars ($5.00). The applicant shall be required to pass an examination in milk testing, reasonably prescribed and conducted by the board, and upon approval of the application shall be issued a certificate of proficiency. Thereupon, and annually thereafter without such examination, the person so certified may apply for a tester's certificate as herein prescribed.
The application for a tester's certificate, accompanied by a fee of five dollars ($5.00), shall be filed, upon a form prescribed by the board, before commencing to test milk, and annually thereafter on or before December first.
The tester's certificate issued hereunder shall be for the term of one calendar year, and shall be posted and kept in plain view in the plant in which the certified tester is employed.
31 P.S. § 700j-602