Fault tree analysis (FTA) is a type of failure analysis in which an undesired state of a system is examined. This analysis method is mainly used in safety engineering and reliability engineering to understand how systems can fail, to identify the best ways to reduce risk and to determine event rates of a safety accident or a particular system level (functional) failure. FTA is used in the aerospace, nuclear power, chemical and process, pharmaceutical, petrochemical and other high-hazard industries; but is also used in fields as diverse as risk factor identification relating to social service system failure. FTA is also used in software engineering for debugging purposes and is closely related to cause-elimination technique used to detect bugs.
SAPHIRE is a probabilistic risk and reliability assessment software tool. SAPHIRE stands for Systems Analysis Programs for Hands-on Integrated Reliability Evaluations. The system was developed for the U.S. Nuclear Regulatory Commission (NRC) by the Idaho National Laboratory.
The United States Nuclear Regulatory Commission (NRC) is an independent agency of the United States government tasked with protecting public health and safety related to nuclear energy. Established by the Energy Reorganization Act of 1974, the NRC began operations on January 19, 1975, as one of two successor agencies to the United States Atomic Energy Commission. Its functions include overseeing reactor safety and security, administering reactor licensing and renewal, licensing radioactive materials, radionuclide safety, and managing the storage, security, recycling, and disposal of spent fuel.
In the field of human factors and ergonomics, human reliability is the probability that a human performs a task to a sufficient standard. Reliability of humans can be affected by many factors such as age, physical health, mental state, attitude, emotions, personal propensity for certain mistakes, and cognitive biases.
Probabilistic risk assessment (PRA) is a systematic and comprehensive methodology to evaluate risks associated with a complex engineered technological entity or the effects of stressors on the environment.
WASH-1400, 'The Reactor Safety Study was a report produced in 1975 for the Nuclear Regulatory Commission by a committee of specialists under Professor Norman Rasmussen. It "generated a storm of criticism in the years following its release". In the years immediately after its release, WASH-1400 was followed by a number of reports that either peer reviewed its methodology or offered their own judgments about probabilities and consequences of various events at commercial reactors. In at least a few instances, some offered critiques of the study's assumptions, methodology, calculations, peer review procedures, and objectivity. A succession of reports, including NUREG-1150, the State-of-the-Art Reactor Consequence Analyses and others, have carried-on the tradition of PRA and its application to commercial power plants.
Spent fuel pools (SFP) are storage pools for spent fuel from nuclear reactors. They are typically 40 or more feet (12 m) deep, with the bottom 14 feet equipped with storage racks designed to hold fuel assemblies removed from reactors. A reactor's local pool is specially designed for the reactor in which the fuel was used and is situated at the reactor site. Such pools are used for short-term cooling of the fuel rods. This allows short-lived isotopes to decay and thus reduces the ionizing radiation and decay heat emanating from the rods. The water cools the fuel and provides radiological protection from its radiation.
The AP1000 is a nuclear power plant designed and sold by Westinghouse Electric Company. The plant is a pressurized water reactor with improved use of passive nuclear safety and many design features intended to lower its capital cost and improve its economics.
NUREG-1150 "Severe Accident Risks: An Assessment for Five U.S. Nuclear Power Plants", published December 1990 by the Nuclear Regulatory Commission (NRC) is a follow-up to the WASH-1400 and CRAC-II safety studies that employs the methodology of plant-specific Probabilistic Risk Assessment (PRA). The research team, led by Denwood Ross, Joseph Murphy, and Mark Cunningham, concluded that the current generation of nuclear power plants exceeded NRC safety goals.
Nuclear safety in the United States is governed by federal regulations issued by the Nuclear Regulatory Commission (NRC). The NRC regulates all nuclear plants and materials in the United States except for nuclear plants and materials controlled by the U.S. government, as well those powering naval vessels.
The Atomic Energy Regulatory Board (AERB) was constituted on 15 November 1983 by the President of India by exercising the powers conferred by Section 27 of the Atomic Energy Act, 1962 to carry out certain regulatory and safety functions under the Act. The regulatory authority of AERB is derived from the rules and notifications promulgated under the Atomic Energy Act, 1962 and the Environmental (Protection) Act, 1986. The headquarters is in Mumbai.
In science, engineering, and research, expert elicitation is the synthesis of opinions of authorities of a subject where there is uncertainty due to insufficient data or when such data is unattainable because of physical constraints or lack of resources. Expert elicitation is essentially a scientific consensus methodology. It is often used in the study of rare events. Expert elicitation allows for parametrization, an "educated guess", for the respective topic under study. Expert elicitation generally helps quantify uncertainty.
Core damage frequency (CDF) is a term used in probabilistic risk assessment (PRA) that indicates the likelihood of an accident that would cause severe damage to a nuclear fuel in a nuclear reactor core. Core damage accidents are considered extremely serious because severe damage to the fuel in the core prevents adequate heat removal or even safe shutdown, which can lead to a nuclear meltdown. Some sources on CDF consider core damage and core meltdown to be the same thing, and different methods of measurement are used between industries and nations, so the primary value of the CDF number is in managing the risk of core accidents within a system and not necessarily to provide large-scale statistics.
Norman C. Rasmussen was an American physicist.
A Technique for Human Event Analysis (ATHEANA) is a technique used in the field of human reliability assessment (HRA). The purpose of ATHEANA is to evaluate the probability of human error while performing a specific task. From such analyses, preventative measures can then be taken to reduce human errors within a system and therefore lead to improvements in the overall level of safety.
Laban L. Coblentz is an American writer, educator, science policy adviser, international civil servant, and entrepreneur. He is an avid proponent of the use of advanced technology for sustainable development. Since 2015, Coblentz has served as the Head of Communication of ITER, the international nuclear fusion research and engineering megaproject and the largest scientific cooperation in history.
Wolfgang Kröger has been full professor of Safety Technology at the ETH Zurich since 1990 and director of the Laboratory of Safety Analysis simultaneously. Before being elected Founding Rector of International Risk Governance Council (IRGC) in 2003, he headed research in nuclear energy and safety at the Paul Scherrer Institut (PSI). After his retirement early 2011 he became the Executive Director of the newly established ETH Risk Center. He has both Swiss and German citizenship and lives in Kilchberg, Zürich. His seminal work lies in the general area of reliability, risk and vulnerability analysis of large-scale technical systems, initially single complicated systems like nuclear power plants of different types and finally complex engineered networks like power supply systems, the latter coupled to other critical infrastructure and controlled by cyber-physical systems. He is known for his continuing efforts to advance related frameworks, methodology, and tools, to communicate results including uncertainties as well as for his successful endeavor in stimulating trans-boundary cooperation to improve governance of emerging systemic risks. His contributions to shape and operationalize the concept of sustainability and - more recently - the concept of resilience are highly valued. Furthermore, he is in engaged in the evaluation of smart clean, secure, and affordable energy systems and future technologies, including new ways of exploiting nuclear energy. The development and certification of cooperative automated vehicles, regarded as a cornerstone of future mobility concepts, are matter of growing interest.
Mohammad Modarres is an Iranian American scientist and educator in the fields of nuclear and reliability engineering. He is a Distinguished Scholar-Teacher and Nicole Y. Kim Eminent Professor of the University of Maryland. Within the University of Maryland A. James Clark School of Engineering, Modarres founded world's first graduate curriculum in reliability engineering, which has now become a leading academic program both nationally and internationally with over 400 Master's and PhD graduates. As the Director of the UMD Center for Risk and Reliability, Modarres serves as international expert on reliability and risk analysis to various commercial and government organizations including US DOE, US NRC, NASA. A PhD graduate of the Massachusetts Institute of Technology, from the scientific school of Norman C. Rasmussen, he has authored numerous books and hundreds of scholarly papers in the fields of nuclear and reliability engineering.
Katrina Groth is an American mechanical engineer and professor. Groth is an associate professor in Mechanical Engineering at the University of Maryland, College Park, where she is the associate director for research for the Center for Risk and Reliability and the director of the Systems Risk and Reliability Analysis lab (SyRRA). Groth previously served as the Principal Research & Development Engineer at Sandia National Laboratories.
A high explosive violent reaction (HEVR) includes reactions ranging from a fast deflagration of the high explosive (HE), up to and including a detonation of the high explosive. The explosive wave may be subsonic or supersonic.
