[Code of Federal Regulations] [Title 31, Volume 3] [Revised as of July 1, 2005] From the U.S. Government Printing Office via GPO Access [CITE: 31CFR540.306] [Page 218] TITLE 31--MONEY AND FINANCE: TREASURY CHAPTER V--OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY PART 540_HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS--Table of Contents Subpart C_General Definitions Sec. 540.306 Highly Enriched Uranium (HEU). The term highly enriched uranium or HEU means uranium enriched to twenty (20) percent or greater in the isotope U235. [[Page 219]]