ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
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The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
Materials in Nuclear Energy Systems (MiNES 2023)
December 10–14, 2023
New Orleans, LA|New Orleans Marriott
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First container of test glass filled at Hanford’s Vit Plant
Bechtel and the Department of Energy’s Office of Environmental Management announced on December 4 that the first set of test glass was successfully poured into a stainless-steel storage container designed to hold vitrified waste at Hanford’s Waste Treatment and Immobilization Plant, also known as the Vit Plant.
Each year ANS provides testimony on Department of Energy (DOE) programs to the House and Senate Energy and Water Appropriations Subcommittees for the upcoming fiscal year. The testimony looks to further advance nuclear-related federal funding and nuclear-related policy issues. For more information on the federal budget process click here.
Download FY 2024 Testimony
ANS formed the Nuclear Waste Policy Task Force in 2019 to interact with policymakers, government representatives, and the public on spent fuel and high-level radioactive waste management issues.
The issue of nuclear waste policy is of paramount importance for the nuclear technology community. Effective radioactive waste management is necessary to allow for the application of nuclear technology. In particular, this refers to restricting the development of advanced reactors which would provide reliable, carbon-free energy if the waste issue is not sufficiently addressed.
In June 2019, ANS Nuclear Waste Policy Task Force Chair Steve Nesbit provided testimony for a hearing before the Senate Energy and Natural Resources Committee. The purpose of the hearing was to examine options for the interim and long-term storage of nuclear waste and to consider S.1234, the Nuclear Waste Administration Act of 2019.
Download a Copy of the Task Force Issue Brief:
Proposal for Progress on Nuclear Waste Management
ANS Nuclear Waste Policy Task Force Roster:
Considering past performances, likelihood of events, and what is important and essential – and what isn’t – is at the heart of risk-informed, performance-based regulation. Prescriptive standards and regulations codify experience without providing flexibility. Standards and regulations ought to evolve instead with our scientific understanding of the technology and risks.
ANS supports regulatory reform that improves plant performance by leveraging risk-informed and performance-based analysis to focus on the most safety-significant issues while explicitly identifying performance outcomes, setting objective criteria, and measuring performance.
Read through some of the background information and simplified definitions on risk-informed and performance-based principles. Also, read more about what ANS is doing to support the incorporation of these concepts in standards.
What are risk-informed, performance-based principles?
Risk-Informed, Performance-Based (RIPB) principles enable an economical implementation of a graded approach so that resources and higher quality expectations are associated with the most important activities contributing to the desired outcome (e.g. safety, economics, plant availability).
What is risk-informed decision making?
It is a process where risk insights are considered together with other sources of insights (e.g. deterministic analysis, safety margin, engineering design features) that considers a broad set of potential challenges to safety and provides a logical means for prioritizing these challenges.
A risk assessment is needed to make a risk-informed decision. An assessment will look at three parts:
Insights gained from conducting a risk assessment can then allow for better resource allocation by focusing on more risk-significant issues identified in the assessment.
The consensus in the engineering community is that a risk-informed analysis is the best source of information for priority setting and resource allocation.
What is a Performance-based approach?
An approach that relies upon the desired, measurable results or performance outcomes based on objective criteria rather than a prescriptive process, technique, or procedure.
Basically, performance-based approaches seek to explicitly identify performance objectives that collectively represent the desired outcome of a project and look at the result of a design or regulation to assess the performance. It formally allows for more flexibility in meeting performance criteria.
A performance-based approach must follow some basic steps:
The engineering community believes that focusing on the performance objectives instead of a prescriptive “how-to” design approach will allow for more innovation in methods without sacrificing adequacy of safety requirements.
What do the regulators say?
The U.S. Nuclear Regulatory Commission (NRC) has been working to add RIPB regulations since 1994 with the development of the Probabilistic Risk Assessment Implementation Plan. That’s because the majority of the regulations are based on deterministic and prescriptive requirements i.e. what can go wrong and how to fix the problem. The majority of the current regulations were developed without considering numerical estimates of risk. Without incorporating risk assessments into the regulations, the NRC assumed that undesirable events can occur and required plant designers to include safety systems and defense-in-depth principles capable of preventing and/or mitigating the consequences of accidents.
In 1999, the NRC adopted the following definition: An approach in which risk insights, engineering analysis and judgment including the principle of defense-in-depth and the incorporation of safety margins, and performance history are used, to (1) focus attention on the most important activities, (2) establish objective criteria for evaluating performance, (3) develop measurable or calculable parameters for monitoring system and licensee performance, (4) provide flexibility to determine how to meet the established performance criteria in a way that will encourage and reward improved outcomes, and (5) focus on the results as the primary basis for safety decision-making. [SRM-SECY-98-0144].
The current belief is that using RIPB concepts will guide NRC requirements and regulatory attention to the issues that are most important to the health and safety of the public and the environment; and identify performance measures that ensure an adequate safety margin.
ANS supports the move to incorporate more RIPB principles in federal regulations and ANSI accredited standards through multiple programs.
ANS published Position Statement 46, Risk-informed and performance-based regulations for nuclear power plants, in 2017 in support of RIPB regulations. With this position statement ANS "supports and advocates for Risk-Informed and Performance-Based (RIPB) safety design and licensing approaches because such approaches will assure protection of public health and safety in the most effective, efficient, and transparent manner. The RIPB approach is a set of methodologies that work to realize graded safety along with efficient priority setting.”
The ANS/ASME Joint Committee on Nuclear Risk Management (JCNRM)
The ANS/ASME Joint Committee on Nuclear Risk Management (JCNRM) Consensus Committee focuses on writing consensus standards that establish safety and risk criteria and methods for completion of probabilistic risk analysis (PRA) and risk assessments. The flagship standard for the JCNRM is ANSI/ASME/ANS RA-S-2008(R2019), Standards for level 1/large early release frequency probabilistic risk assessment for nuclear power plant applications, which is currently being revised. The other big project currently in production is the ASME/ANS RA-S-1.4-2013, Probabilistic risk assessment standard for advanced non-light water reactor (NLWR) nuclear power plants. In September 2019, the JCNRM decoupled the NLWR standard from the next edition of the Level 1/LERF standard to ensure it would be available by the end of 2020 to support regulatory applications.
Risk-informed, Performance-based Principles and Policy Committee (RP3C)
The ANS Standards Board has established the Risk-informed, Performance-based Principles and Policy Committee (RP3C) as a committee that reports directly to the Standards Board. The RP3C is responsible for the identification and oversight of the development and implementation of the ANS Risk-Informed and Performance-Based Standards Plan that establishes the approaches, priorities, responsibilities and schedules for implementation of risk-informed and performance-based principles in ANS standards. These principles are applicable to standards that address the design, construction, operation, evaluation and analysis, decontamination and decommissioning, waste management, and environmental restoration for nuclear facilities.
Radioisotopes go unnoticed for their everyday applications, from life-saving cancer treatments and oil/gas well-logging to extending produce shelf life and sterilizing medical devices, implants and supplies.
from nuclear news
The nexus between safety and operational performance. Over the past 20 years, the nuclear industry’s efforts to improve plant performance have taken a risk-informed approach that focuses resources on the most safety-significant issues.
Risk-informed, performance-based safety: Past, present, and future. Risk-informed and performance-based approaches to nuclear safety have saved money and improved safety for current reactors and have the potential to offer even greater benefits for advanced reactors.
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Last modified April 24, 2023, 12:39pm CDT