"By-product nuclear material" means a radioactive material, other than special nuclear material, yielded in or made radioactive by exposure to radiation created incident to the process of producing or utilizing special nuclear material.
"Radiation" means ionizing radiation and includes alpha rays; beta rays; gamma rays; x-rays; high energy neutrons, protons, or electrons; and other atomic particles.
"Radioactive material" means a matter that emits radiation. Radioactive material includes special nuclear material, source nuclear material, and by-product nuclear material.
"Source nuclear material" means uranium or thorium, or a combination thereof, in any physical or chemical form; or ores that contain by weight 1/20 of one percent (0.05 percent) or more of uranium, thorium, or a combination thereof. Source nuclear material does not include special nuclear material.
"Special nuclear material" means:
(1) plutonium, uranium enriched in the isotope 233 or in the isotope 235, and any other material that the Nuclear Regulatory Commission determines to be special nuclear material according to United States Code, title 42, section 2071, except that source nuclear material is not included; and
(2) a material artificially enriched by any of the materials listed in clause (1), except that source nuclear material is not included.