[Code of Federal Regulations] [Title 21, Volume 7] [Revised as of April 1, 2001] From the U.S. Government Printing Office via GPO Access [CITE: 21CFR610.41] [Page 74] TITLE 21--FOOD AND DRUGS DEPARTMENT OF HEALTH AND HUMAN SERVICES--(Continued) PART 610--GENERAL BIOLOGICAL PRODUCTS STANDARDS--Table of Contents Subpart E--Hepatitis Requirements Sec. 610.41 History of hepatitis B surface antigen. A person known to have previously tested positive for hepatitis B surface antigen, testing positive, or both, may not serve as a donor of human blood, plasma, or serum, except that under Sec. 640.120 of this chapter, such a donor may serve as a source of hepatitis B surface antigen for the manufacture of hepatitis B vaccine or the preparation of a diagnostic product for laboratory tests, or a person known to have previously tested positive for hepatitis B surface antigen may serve as a source of antibody to hepatitis B surface antigen for the preparation of a biological product or a diagnostic product for laboratory tests. [48 FR 23182, May 24, 1983, as amended at 57 FR 10814, Mar. 31, 1992]