[Code of Federal Regulations] [Title 42, Volume 1] [Revised as of October 1, 2005] From the U.S. Government Printing Office via GPO Access [CITE: 42CFR7.3] [Page 54] TITLE 42--PUBLIC HEALTH CHAPTER I--PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES PART 7_DISTRIBUTION OF REFERENCE BIOLOGICAL STANDARDS AND BIOLOGICAL PREPARATIONS--Table of Contents Sec. 7.3 Definitions. Biological standards means a uniform and stable reference biological substance which allows measurements of relative potency to be made and described in a common currency of international and national units of activity. Biological preparations means a reference biological substance which may be used for a purpose similar to that of a standard, but which has been established without a full collaborative study, or where a collaborative study has shown that it is not appropriate to establish the preparation as an international standard.