R 325.5005 Definitions; B.

Rule 5. (1) "Barrier" includes a primary protective barrier, a secondary protective barrier, or a personnel barrier. (2) "Beam axis" means a line from the source through the centers of the gamma-ray fields. (3) "Beam-limiting device" means a device which provides a means to restrict the dimensions of the gamma-ray field. (4) "Byproduct material" means any radioactive material, except special nuclear material, yielded in or made radioactive by exposing it to the radiation incident to the process of producing or utilizing special nuclear material.