[Code of Federal Regulations] [Title 10, Volume 1] [Revised as of January 1, 2005] From the U.S. Government Printing Office via GPO Access [CITE: 10CFR39.47] [Page 631] TITLE 10--ENERGY CHAPTER I--NUCLEAR REGULATORY COMMISSION PART 39_LICENSES AND RADIATION SAFETY REQUIREMENTS FOR WELL LOGGING --Table of Contents Subpart C_Equipment Sec. 39.47 Radioactive markers. The licensee may use radioactive markers in wells only if the individual markers contain quantities of licensed material not exceeding the quantities specified in Sec. 30.71 of this chapter. The use of markers is subject only to the requirements of Sec. 39.37.