7 Pa. Code § 1.343
When any chemical, preservative, cereal, spice, or other substance is intended for use in an official establishment it shall be examined by a program employe and if found to be unfit or otherwise unacceptable for the use intended, or if final decision regarding acceptance is deferred pending laboratory or other examination, the employee shall attach a "Pa. Retained" tag to the substance or container thereof. The substance so tagged shall be kept separate from other substances as the veterinary supervisor may require and shall not be used until the tag is removed. Such removal shall be made only by a program employe after a finding that the substance can be accepted or, in the case of an acceptable substance, when it is removed from the establishment.
7 Pa. Code § 1.343