Nuclear energy and radiation terminology · MLC-0119

Nuclear energy and radiation terms: R (55)

• Rad (radiation absorbed dose)One of the two units used to measure the amount of radiation absorbed by an object or person, known as the...
• Radiation areaAny area with radiation levels greater than 5 millirems (0.05 millisievert) in one hour at 30 centimeters...
• Radiation detection instrumentA device that detects and displays the characteristics of ionizing radiation.
• Radiation, ionizingA form of radiation, which includes alpha particles, beta particles, gamma rays, x-rays, neutrons, high-speed...
• Radiation (ionizing radiation)Alpha particles, beta particles, gamma rays, x-rays, neutrons, high-speed electrons, high-speed protons, and...
• Radiation, nuclearEnergy given off by matter in the form of tiny, fast-moving particles (alpha particles, beta particles, and...
• Radiation shieldingReduction of radiation by interposing a shield of absorbing material between any radioactive source and a...
• Radiation sickness (syndrome)The complex of symptoms characterizing the disease known as radiation injury, resulting from excessive...
• Radiation sourceA radioactive material or byproduct that is specifically manufactured or obtained for the purpose of using...
• Radiation standardsExposure limits; permissible concentrations; rules for safe handling; and regulations regarding receipt...
• Radiation therapy (radiotherapy)The therapeutic use of ionizing radiation to treat disease in patients. Although most radiotherapy procedures...
• Radiation warning symbolAn officially prescribed magenta or black trefoil on a yellow background, which must be displayed where...
• Radioactive contaminationUndesirable radioactive material (with a potentially harmful effect) that is either airborne or deposited in...
• Radioactive decayThe spontaneous transformation of one radionuclide into one or more decay products (also known as...
• Radioactive seriesA succession of nuclides, each of which transforms by radioactive disintegration into the next until a stable...
• RadioactivityThe property possessed by some elements (such as uranium) of spontaneously emitting energy in the form of...
• RadiographyThe use of sealed sources of ionizing radiation for nondestructive examination of the structure of materials...
• Radioisotope (Radionuclide)An unstable isotope of an element that decays or disintegrates spontaneously, thereby emitting radiation...
• Radiological sabotageAny deliberate act directed against a plant or transport in which an activity licensed pursuant to 10 CFR...
• Radiological surveyThe evaluation of the radiation hazards accompanying the production, use, or existence of radioactive...
• RadiologyThat branch of medicine dealing with the diagnostic and therapeutic applications of radiant energy, including...
• RadionuclideAn unstable isotope of an element that decays or disintegrates spontaneously, thereby emitting radiation...
• RadiopharmaceuticalA pharmaceutical drug that emits radiation and is used in diagnostic or therapeutic medical procedures...
• RadiosensitivityThe relative susceptibility of cells, tissues, organs, organisms, or other substances to the injurious action...
• RadiumA radioactive substance found in nature. The Energy Policy Act of 2005 gives the NRC regulatory authority for...
• RadonA radioactive element that is one of the heaviest gases known. Its atomic number is 86. It is a daughter of...
• ReactionAny process involving a chemical or nuclear change.
• Reactive InspectionAn inspection to examine the circumstances surrounding an operational problem or event occurring at a nuclear...
• ReactivityA term expressing the departure of a reactor system from criticality. A positive reactivity addition...
• Reactor coolant systemThe system used to remove energy from the reactor core and transfer that energy either directly or indirectly...
• Reactor coreThe central portion of a nuclear reactor, which contains the fuel assemblies, moderator, neutron poisons...
• Reactor, nuclearThe heart of a nuclear power plant or nonpower reactor, in which nuclear fission may be initiated and...
• Reactor Oversight ProcessThe process by which the NRC monitors and evaluates the performance of commercial nuclear power plants...
• RealizationOne execution or trial of a probabilistic simulation using a set of deterministic input values sampled from...
• ReasonableRational, sensible, or resulting from sound judgment.
• Reference manA person with the anatomical and physiological characteristics of an average individual that is used in...
• ReflectorA layer of material immediately surrounding a reactor core that scatters back (or reflects) into the core...
• RefuelingThe process of removing older fuel and loading new fuel. These actions are all performed underwater to supply...
• Refueling BWRAs new fuel shipping canisters arrive in the reactor building, the reactor building crane lifts them to the...
• Refueling PWRAs new fuel shipping canisters arrive in the reactor building, the reactor building crane lifts them to the...
• RegulationThe governmental function of controlling or directing economic entities through the process of rulemaking and...
• Regulatory ConferenceA meeting between the NRC and a reactor licensee to discuss an inspection finding that was preliminarily...
• Regulatory Information ConferenceAn annual NRC conference that brings together NRC staff, regulated utilities, materials users, and other...
• RemOne of the two standard units used to measure the dose equivalent (or effective dose), which combines the...
• Renewable resourcesNatural, but limited, energy resources that can be replenished, including biomass, hydro, geothermal, solar...
• Resident InspectorAn NRC inspector assigned to inspect a nuclear plant on a full-time basis. Each site has at least two...
• Restricted areaAny area to which access is controlled for the protection of individuals from exposure to radiation and...
• RiskThe combined answer to three questions that consider (1) what can go wrong, (2) how likely it is to occur...
• Risk significantThe term referring to a facility’s system, structure, component, or accident sequence that exceeds a...
• Risk-based decisionmakingAn approach to regulatory decisionmaking that considers only the results of a probabilistic risk assessment...
• Risk-informed decisionmakingAn approach to regulatory decisionmaking, in which insights from probabilistic risk assessment are considered...
• Risk-informed regulationAn approach to regulation taken by the NRC, which incorporates an assessment of safety significance or...
• RoentgenA unit of exposure to ionizing radiation. It is the amount of gamma or x-rays required to produce ions...
• RubblizationA decommissioning technique involving demolition and burial of formerly operating nuclear facilities. All...
• RuptureA complete break or catastrophic structural failure of a component.

55 of 555 terms in Nuclear energy and radiation terminology (MLC-0119). Request the full dataset.