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Bowen, Douglas G.

Publications and source records attributed to Bowen, Douglas G..

ANS-8 Nuclear Criticality Safety Consensus Standards - Current Initiatives

The nuclear criticality safety (NCS) consensus standards are developed as using rigorous procedures of the Standards Board of the American Nuclear Society. These procedures have been accredited by the American National Standards Institute, Inc., as meeting the criteria for American National Standards. The Nuclear Criticality Safety Consensus Committee (NCSCC) that approved all 18 NCS consensus standards is balanced to ensure that competent, concerned, and varied interests have had an opportunity to participate. The ANS-8 subcommittee (ANS-8) consists of 17 NCS experts with many years of experience as end users of ANS standards who serve on standard working groups to develop and maintain standards. ANS-8 ensures that the technical content of the standards is adequate for NCS community use. Attempts are made to ensure that ANS-8 consists of NCS professionals with a diverse range of experience such that all standards are applicable to as many sites as possible. ANS-8 is a very active subcommittee, and some active projects in progress are discussed in this paper: basis statement development for all standards, development of a glossary for consistency of definitions across all ANS-8 standards, and Considering the Criticality Safety Support Group (CSSG) Recommendation 2016-04 to the ANS Standards Board for changes in several ANS-8 standards.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗

Overview and Current Progress of the DOE/NNSA Nuclear Criticality Safety Program Training and Education Program

Since 2011, the US Department of Energy/National Nuclear Security Administration (DOE/NNSA) Nuclear Criticality Safety Program (NCSP) has been providing a two-week nuclear criticality safety (NCS) practitioner course to support the training and qualification of new NCS staff. In 2013, an NCS Manager’s course was developed for process supervisors, managers, regulators, and other professionals with NCS-related responsibilities, and, in 2017, an additional course was proposed for Criticality Safety Officers (CSOs). In addition to hands-on training, other NCSP-funded tasks include training on sensitivity/uncertainty methods, NCS resource pipeline tasks, development of NCS guides, maintenance and development of Nuclear Criticality Safety Education Training (NCSET) modules and designing of a new subcritical assembly for hands-on training purposes. This paper provides an overview of the NCSP training and education program. The status of the NCSP hands-on training program will also be provided.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗

Status of ANS-8 and TC85/SC5/WG8 NCS Consensus Standards [Slides]

This presentation covers ANS-8 and its status. The presentation starts with an introduction into ongoing projects. Including touching upon on ANS standard development steps and a status report. Finally, the lecture covers ISO WG8 Standards. with a special focus on recent ISO TC85/SC5 Plenary in Tsukuba, Japan and ISO development process + road map and a final status report.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗

Conduct of Operations and Nuclear Criticality Safety Standards

Since the beginning of the nuclear age in 1943, there have been 22 criticality accidents in process facilities worldwide in which fissionable materials were processed by hand for various purposes. Of these 22 process criticality accidents, 16 involved faulty or flawed conduct of operations. Most of these process accidents (17 of 22) occurred before 1970, mostly due to the implementation of formal conduct of operations—such as the use of operating procedures and training—and the use of consensus standards for nuclear criticality safety (NCS). Obviously, the nuclear facilities applied lessons learned from their accident history, and the rate of criticality accidents was significantly reduced as a result. Over the years, it has been emphasized in NCS training courses and other venues in the United States that the consensus standards, such as ASA N6.1-1964, were the key contributors to this reduction in accidents. The formality of operations required to implement and apply the standards at a facility is also a crucial prerequisite that must be sufficiently robust to ensure NCS. This prerequisite is crucial to success fully implement the NCS consensus and other safety standards at a site.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

Formality of Operations and Nuclear Criticality Safety Standards [Slides]

This presentation is on the formality of operations and nuclear criticality safety standards. This lecture starts with an Introduction then leads into a conversation on the dependencies of formality of operations. Secondly the presentation includes a review of past issues. Included is a Discussion about “credible” and “unlikely” – variables for process analysis in ANS-8.1, Section 4.1.2, and the double contingency principle, Section 4.2.2, respectively. The presentation finishes with some conclusions.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗

Nuclear Criticality Safety Training: Needs and Efforts

Nuclear criticality safety (NCS) training is essential and required for NCS professionals to ensure that fissionable materials outside of nuclear reactors are safely processed, handled, stored, and transported. Furthermore, the requirement of training in NCS is mandated in several international and domestic documents. In this regard, management has an obligation to establish an NCS training program that provides confidence in the continuing proficiency of personnel, and supervisors must ensure that their staff is suitably trained. Training of all personnel in nuclear facilities is required to support the robust performance of operations. There is a continuing need to maintain, enhance, and develop new training courses to support the NCS community. This paper provides an outline of some of the ongoing and future training courses in the United States to support the field of NCS.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Sharing of Good Practices and Lessons Learned [Slides]

This presentation shares good practices and lessons that were learned. Particularly highlighted is the Learning from Experience Database (LFE). Provided are additional slides walking through a visual representation of this system.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗

Hand Calculation Methods for Nuclear Criticality Safety

This primer provides an overview of the most common hand calculation methods used for criticality safety calculations. The most widely used tools available to a nuclear criticality safety (NCS) practitioner are probably the common Monte Carlo or deterministic criticality safety codes, which can be used to model very complex systems. However, use of these codes can obscure the parameters to which a particular fissile system may be sensitive, whereas the hand calculation methods can be used to delve into the ways each parameter may affect the reactivity of a fissile material system. Furthermore, practitioners must avoid using computer codes as devices that take inputs and simply provide outputs (i.e., a “black box”). Many years ago, pioneers such as Joe Thomas, David Smith, and Hugh Paxton, among others in the field of nuclear criticality safety, took the time before the advent of high-speed desktop computers to create simple hand methods for criticality safety analyses. Some of the methods can be used for single fissile units; others are applicable to fissile units arranged into simple array configurations. This primer discusses the applicability of the various methods, illustrates how they are used, and provides an interpretation of the various results. The NCS practitioner will need to spend time to master the methods that could be most useful; however, they can provide the practitioner with fast and accurate answers to criticality safety problems if they are used correctly and if critical data exist for the problem at hand. Hand calculation methods can be used as a starting point for more advanced calculations, and in many circumstances, they can provide sensitivity and perturbation information more quickly than using a criticality code.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

NCSP Nuclear Data Program [Slides]

This talk covers wide-ranging information on the Nuclear Criticality Safety Program (NCSP) Data Program. The Lecture includes slides on the history and mission of the NCSP along with charts and graphs on budgets from 2005 onwards. This lecture additionally mentions NCSP critical assemblies, differential experiments, and data measurements and evaluation work. The talk concludes with a gaze into NCSP benefits and successes.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗