Mass. Gen. Laws ch. 6 § 85
As used in sections eighty-six to ninety-two, inclusive, the following words shall have the following meaning unless the context indicates otherwise:
"Atomic energy", all forms of energy released in the course of nuclear fission or nuclear transformation.
"By-product material", any radio-active material, except special nuclear materials, yielded in or made radio-active by exposure to the radiation incident to the process of producing or utilizing special nuclear materials.
"Operator", any individual who manipulates the controls of a utilization or production facility.
"Production facility", (a) any equipment or device capable of the production of special nuclear material in such quantity as to be of significance to the common defense and security, or in such manner as to affect the health and safety of the public; or (b) any important component part especially designed for such equipment or device.
"Special nuclear material", (a) plutonium and uranium enriched in the isotope 233 or in the isotope 235, and any other material which the governor declares by order to be special nuclear material after the United States Atomic Energy Commission has determined the material to be such; or (b) any material artificially enriched by any of the foregoing.
"Utilization facility", (a) any equipment or device, except an atomic weapon, capable of making use of special nuclear materials in such quantity as to be of significance to the common defense and security, or in such manner as to affect the health and safety of the public, or peculiarly adapted for making use of atomic energy in such quantity as to be of significance to the common defense and security, or in such manner as to affect the health and safety of the public; or (b) any important component part especially designed for such equipment or device.
Mass. Gen. Laws ch. 6, § 85