[Code of Federal Regulations] [Title 10, Volume 1] [Revised as of January 1, 2004] From the U.S. Government Printing Office via GPO Access [CITE: 10CFR35.63] [Page 578] TITLE 10--ENERGY CHAPTER I--NUCLEAR REGULATORY COMMISSION PART 35--MEDICAL USE OF BYPRODUCT MATERIAL--Table of Contents Subpart C--General Technical Requirements Sec. 35.63 Determination of dosages of unsealed byproduct material for medical use. (a) A licensee shall determine and record the activity of each dosage before medical use. (b) For a unit dosage, this determination must be made by-- (1) Direct measurement of radioactivity; or (2) A decay correction, based on the activity or activity concentration determined by-- (i) A manufacturer or preparer licensed under Sec. 32.72 of this chapter or equivalent Agreement State requirements; or (ii) An NRC or Agreement State licensee for use in research in accordance with a Radioactive Drug Research Committee-approved protocol or an Investigational New Drug (IND) protocol accepted by FDA. (c) For other than unit dosages, this determination must be made by- - (1) Direct measurement of radioactivity; (2) Combination of measurement of radioactivity and mathematical calculations; or (3) Combination of volumetric measurements and mathematical calculations, based on the measurement made by a manufacturer or preparer licensed under Sec. 32.72 of this chapter or equivalent Agreement State requirements. (d) Unless otherwise directed by the authorized user, a licensee may not use a dosage if the dosage does not fall within the prescribed dosage range or if the dosage differs from the prescribed dosage by more than 20 percent. (e) A licensee shall retain a record of the dosage determination required by this section in accordance with Sec. 35.2063.