AMERICAN NUCLEAR SOCIETY Standards Committee GLOSSARY OF DEFINITIONS AND TERMINOLOGY May 19, 2016 American National Standard Glossary - May 19, 2016 Foreword This Glossary is an edited compilation of the "Definitions" provided in standards issued by the American Nuclear Society (ANS) Standards Committee. This version includes definitions in standards issued prior to September 1, 2015. The specific standards that were reviewed for this update are listed in Appendix A. This review included new standards from all ANS consensus committees. Older definitions focused on NFSC standards. Over time, as standards are revised, the glossary will be updated so that it fully reflects the definitions used in all ANS standards. Each ANS standard shall include a definitions section that provides clarity for terms used in the standard that may not be commonly understood in the nuclear industry. The Glossary definitions shall be used to provide a consistent set of definitions and to minimize the time-consuming task of developing unique definitions for each document. Terms not contained in the Glossary may be defined by the Working Group and included in the definitions section of the standard. The Glossary is intended to be a living document subject to revision. The Glossary will be provided as a part of the ANS Standards Toolkit available at: • On the ANS website at: http://www.ans.org/standards/resources/ • On ANS Standards Committee Workspace at: https://workspace.ans.org/kws/groups/scmembers/documents?folder_id=915 A definition followed by a (G) means the definition was in the original Glossary, a (C) or (ANS 3.2-[no date]) means the definition came from the 1983 Glossary and that no later version was available for review. In general, this document provides the preferred definition in the Glossary followed by non-preferred alternate definition variations that have been used in other standards. The source document for each definition is identified at the end of each definition (e.g., ANS 3.2-1989). Standards with exact duplicate definitions are also identified, as well as those documents which contain a variant form. The goal of identifying preferred and alternate definitions is to assist the standards working groups (WG) in selection of definitions and to eventually standardize all definitions used in ANS standards. The WG shall: 1. Use the preferred definition unless it is not applicable to the subject of the stand- ard or confusion would be created, 2. If the preferred definition is not applicable, use one of the alternate definitions, 3. If none-of the included definitions are applicable, an alternate term or alternate definition may be substituted with a footnote stating the reason for use of a new definition. The formats for preferred and alternate definitions are shown in the following Format Sample. The alternate definitions have a lead in “non-preferred variation (x)” where x is 1 for the first alternate definition, 2 for the second, etc. The alternate definitions are indented. i American National Standard Glossary - May 19, 2016 The preferred definitions have been selected based on general applicability, the number of standards, the hierarchy and age of the standards using the definition. For example, a new issue of ANS-50.1 would be preferred over a definition used for a detailed specific subject standard. A definition used in ten standards would be preferred over a definition used in only one. A definition of general applicabil- ity would be preferred over one unique to a particular application. Where similar, but not identical, terms are identified, the glossary identifies terms that should be subordinate and its definition replaced by reference in whole or part to the preferred term. When issuing a new or revised standard for ballot review, the WG shall highlight 1) any changes to the definitions in the standard, 2) any definitions that are not currently in the glossary, and 3) any uses of alternate definitions. Suggested Definition Changes Questions, suggestions for changes or additions to the Glossary should be addressed to ANS Standards Manager at: [email protected] Format Sample core damage. Any physical disruption of the nuclear core including fuel, fission products, and containing geometry consisting of cladding, structure, and flow alignment that could release significant amounts of radioactivity from fission products by being undercooled or overreactive. (ANS-53.1-2011) non-preferred variation (1) - Uncovery and heatup of the reactor core to the point at which prolonged oxidation and severe fuel damage are anticipated and involving enough of the core, if released, to result in offsite public health effects. (ASME/ANS RA-Sb–2013) For information only - For additional definitions, refer to: Nuclear Regulatory Commission Glossary at http://www.nrc.gov/reading-rm/basic-ref/glossary.html#N IAEA Nuclear Safety Glossary at: http://www-pub.iaea.org/MTCD/publications/PDF/Pub1290_web.pdf European Nuclear Society Glossary of Nuclear Terms at http://www.euronuclear.org/info/encyclopedia/pdf/Nuclear%20Glossary,2008-04- 04.pdf The Language of the Nucleus at: : http://www.nuclearglossary.com/index.html ii American National Standard Glossary - May 19, 2016 A. abnormal conditions and events (ACEs). Conditions and events identified as a result of system considerations or from specific software design and implementation that have the potential for incorrect execution of the software. Thus, ACEs include conditions and events internal to computer hardware or software. Examples of ACEs due to inadequate design and implementation are buffer overf lows, input/output timing, initializations status, out of sequence of subroutines (ANS-10.7-2013) abnormal radionuclide release. The unplanned or uncontrolled emission of an effluent (i.e., containing plant-related, licensed radioactive material). (ANS-2.17-2010) absorbed dose (D). The quotient of de by dm where de is the mean energy imparted by ionizing radiation to matter of mass dm: de D= dm The special name for the unit of absorbed dose in the gray (Gy); 1 Gy = 1J/kg. [based on ICRU Rpt. 33 & Publication 26]. (ANS 6.1.1-91) Variant form: (ANS 3.7.1-D92) academic training. Success-fully completed college level work leading to a recognized degree in a discipline related to the position in question. (ANS-3.1) acceleration sensor. An instrument capable of sensing absolute acceleration and producing a signal that could be transmitted to a recorder. (ANS-2.2-02) accelerogram. A representation (either recorded, modified recorded, or synthetic) of the acceleration of the ground during an earthquake. The accelerogram contains acceleration- time-data pairs.(ANSI/ANS 2.27-2008) Non-preferred variation (1) The record of acceleration varying with time for a single linear component of vibration, recorded by a time history accelerograph. (ANS 2.10- 2003) acceptable. The word "acceptable" is used when a system or component has been demonstrated to meet its design and performance criteria by test or analysis. (ANS 56.5- 89) acceptable damage. Damage resulting from an event (or appropriate combinations of events) where the safety design requirements for the appropriate category of events are met. Events (and appropriate combinations of events) are categorized by plant conditions in ANSI/ANS-51.1 and 52.1. (ANS 58.3-92) (ANS 58.3-98) acceptable level of safety. The aggregate of an individual facility's conditions found on case-by-case basis to be adequate to assure protection of the worker and public health and safety considering the probability and consequences of adverse events including the expected response of that facility to those events. (58.3)(58.4-W90) acceptable method. In many places, the commentary contains words such as, “Reference X provides an acceptable method for performing this aspect of the analysis.” The plain meaning of this wording should be clear, namely that using the methodology or data or 1 American National Standard Glossary - May 19, 2016 approach in Reference X is one way to meet the Standard. The intent of any Requirement that uses this language is to be permissive, meaning that the analysis team can use another method without prejudice. However, it is important to understand that the intent of the Standard goes beyond the plain meaning, as follows: Whenever the phrasing “acceptable method” is used herein, the intent is that if the analysis uses another method, the other method must accomplish the stated objective with a comparable level of detail, a compara- ble scope, a comparable level of conservatism, etc. It is not acceptable to use another method that does not accomplish the intent of the Requirement at least as well as the “acceptable method” would accomplish it. Whenever an alternative to the “acceptable method” is selected, it is understood that the peer-review team will pay particular attention to this topic. (ANSI/ANS-2.29—2008) acceptance criteria. The standard, with a tolerance, against which test results are to be compared for establishing the functional acceptability. (ANS-10.8-2015) Non-preferred variation (1) Actionable, measureable guidance for evaluating tests, inspections, and performance.(ANS-53.1-2011) Non-preferred variation (2) The standard against which test results are to be compared for establishing the functional acceptability of the primary containment as a leakage- limiting boundary. (ANS-56.8-02) access control station. A station established to control access between controlled and uncontrolled areas. Its function is to assure that only authorized personnel, properly equipped, may enter into controlled access areas, and that personnel leaving controlled access have been cleared by the radiation monitors. (ANS-6.7.1-85) Variant form: (ANS-5.6.1-85) accessible instruments. Instruments or sensors whose locations permit ready access during plant operation without violation of applicable safety regulations such as those of the Occupational Safety and Health Administration (OSHA), or regulations that address plant security or radiation protection safety.