31 Pa. Stat. § 700j-603
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 samples taken for testing purposes shall be made by a certified tester or certified weigher and sampler, and according to the method prescribed in this act or in regulations established by the board under this act.
It shall be unlawful for any person to pick up milk from farms unless the person making the pickup has a valid tester's certificate or weigher's or sampler's certificate issued by the board.
Any person who, upon the effective date of this act, is the holder of a certificate of proficiency for milk weighing and sampling 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 apparatus and methods used in weighing and sampling, be issued a certificate and be designated therein as a certified weigher and sampler.
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 weighing and sampling 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 weighing and sampling milk, 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 certificate as a certified weigher and sampler. The application for such weighing and sampling certificate, accompanied by a fee of five dollars ($5.00), shall be filed, upon a form prescribed by the board, before commencing to sample milk, and annually thereafter on or before December first.
The weighing and sampling certificate issued hereunder shall be for the term of one calendar year, and shall be posted and kept in plain view in the room in which the certified weigher and sampler is employed.
31 P.S. § 700j-603