[Code of Federal Regulations] [Title 21, Volume 7] [Revised as of April 1, 2008] From the U.S. Government Printing Office via GPO Access [CITE: 21CFR660.26] [Page 123] TITLE 21--FOOD AND DRUGS CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) PART 660_ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS-- Subpart C_Blood Grouping Reagent Sec. 660.26 Specificity tests and avidity tests. Specificity and avidity tests shall be performed using test procedures approved by the Director, Center for Biologics Evaluation and Research. [53 FR 12764, Apr. 19, 1988, as amended at 67 FR 9587, Mar. 4, 2002; 70 FR 14985, Mar. 24, 2005]