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Potential Improvements to the Nuclear Safety and Launch Approval https://ntrs.nasa.gov/search.jsp?R=20190001430 2019-04-04T13:49:59+00:00Z NASA/TM2019-220256 Potential Improvements to the Nuclear Safety and Launch Approval Process for Nuclear Reactors Utilized for Space Power and Propulsion Applications A Report to the Nuclear Power & Propulsion Technical Discipline Team Allen Camp Consultant, Albuquerque, New Mexico Andy Klein Oregon State University, Corvallis, Oregon Patrick McClure Los Alamos National Laboratory, Los Alamos, New Mexico Pete McCallum NASA Glenn Research Center, Cleveland, Ohio Susan Voss Global Nuclear Network Analysis, LLC, Taos, New Mexico February 2019 NASA STI Program . in Profile Since its founding, NASA has been dedicated to the CONFERENCE PUBLICATION. advancement of aeronautics and space science. The Collected papers from scientific and NASA scientific and technical information (STI) technical conferences, symposia, seminars, program plays a key part in helping NASA maintain or other meetings sponsored or this important role. co-sponsored by NASA. The NASA STI program operates under the SPECIAL PUBLICATION. Scientific, auspices of the Agency Chief Information Officer. technical, or historical information from It collects, organizes, provides for archiving, and NASA programs, projects, and missions, disseminates NASA’s STI. The NASA STI often concerned with subjects having program provides access to the NTRS Registered substantial public interest. and its public interface, the NASA Technical Reports Server, thus providing one of the largest TECHNICAL TRANSLATION. collections of aeronautical and space science STI in English-language translations of foreign the world. Results are published in both non-NASA scientific and technical material pertinent to channels and by NASA in the NASA STI Report NASA’s mission. Series, which includes the following report types: Specialized services also include organizing and publishing research results, distributing TECHNICAL PUBLICATION. Reports of specialized research announcements and feeds, completed research or a major significant phase providing information desk and personal search of research that present the results of NASA support, and enabling data exchange services. Programs and include extensive data or theoretical analysis. Includes compilations of For more information about the NASA STI significant scientific and technical data and program, see the following: information deemed to be of continuing reference value. NASA counter-part of peer- Access the NASA STI program home page reviewed formal professional papers but has at http://www.sti.nasa.gov less stringent limitations on manuscript length and extent of graphic presentations. E-mail your question to [email protected] TECHNICAL MEMORANDUM. Scientific Phone the NASA STI Information Desk at and technical findings that are preliminary or of 757-864-9658 specialized interest, e.g., quick release reports, working papers, and bibliographies that contain Write to: minimal annotation. Does not contain extensive NASA STI Information Desk analysis. Mail Stop 148 NASA Langley Research Center CONTRACTOR REPORT. Scientific and Hampton, VA 23681-2199 technical findings by NASA-sponsored contractors and grantees. NASA/TM2019-220256 Potential Improvements to the Nuclear Safety and Launch Approval Process for Nuclear Reactors Utilized for Space Power and Propulsion Applications A Report to the Nuclear Power & Propulsion Technical Discipline Team Allen Camp Consultant, Albuquerque, New Mexico Andy Klein Oregon State University, Corvallis, Oregon Patrick McClure Los Alamos National Laboratory, Los Alamos, New Mexico Pete McCallum NASA Glenn Research Center, Cleveland, Ohio Susan Voss Global Nuclear Network Analysis, LLC, Taos, New Mexico National Aeronautics and Space Administration Langley Research Center Hampton, Virginia 23681-2199 February 2019 Acknowledgments This study was chartered by NASA’s Nuclear Power & Propulsion Technical Discipline Team (TDT) led by Lee Mason and Mike Houts. The Nuclear Power & Propulsion TDT governance resides under the NASA Office of Chief Engineer with oversight by the NASA Engineering Safety Center (NESC) Power Technical Fellow (Chris Iannello) and Propulsion Technical Fellow (Tom Brown). The study team would like to thank them along with the other members of the TDT for their guidance and feedback during this effort. The use of trademarks or names of manufacturers in the report is for accurate reporting and does not constitute an official endorsement, either expressed or implied, of such products or manufacturers by the National Aeronautics and Space Administration. Available from: NASA STI Program / Mail Stop 148 NASA Langley Research Center Hampton, VA 23681-2199 Fax: 757-864-6500 Table of Contents Executive Summary .................................................................................................................................... 1 1.0 Introduction .................................................................................................................................... 4 1.1 Objectives ........................................................................................................................... 4 1.2 Scope ................................................................................................................................... 4 1.3 Methodology ....................................................................................................................... 5 2.0 A Brief History of Safety for Space Reactors .............................................................................. 6 2.1 Systems for Nuclear Auxiliary Power (SNAP) Program .................................................... 8 2.2 Rover/NERVA Thermal Nuclear Rocket Program ............................................................. 9 2.3 Space Power 100 kWe (SP-100) ....................................................................................... 10 2.4 Topaz II ............................................................................................................................. 11 2.5 Prometheus........................................................................................................................ 11 2.6 Historical Efforts to Prevent Inadvertent Criticality ......................................................... 12 2.7 Summary ........................................................................................................................... 13 2.8 Impacts to Current Programs ............................................................................................ 13 3.0 Current Launch Safety Process .................................................................................................. 14 3.1 Launch Process Overview................................................................................................. 14 3.2 Considerations for Fission Reactors ................................................................................. 16 4.0 Assessment of Areas for Improvement ...................................................................................... 17 4.1 Duplication........................................................................................................................ 17 4.2 Complexity........................................................................................................................ 19 4.3 Roles and Responsibilities ................................................................................................ 19 5.0 General Design Criteria .............................................................................................................. 20 6.0 Safety Criteria .............................................................................................................................. 20 6.1 Need for Explicit Criteria.................................................................................................. 20 6.2 Approach to Development of Safety Criteria ................................................................... 21 6.3 Recommended Risk Criteria for Space Nuclear Reactors ................................................ 23 6.3.1 Likelihood Criterion for Inadvertent Criticality Accidents ............................................... 23 6.3.2 Likelihood Criterion for Hot Reentry ............................................................................... 25 6.3.3 Public Health Criterion ..................................................................................................... 26 6.3.4 Consistency with Other Federal Regulatory Approaches ................................................. 28 7.0 Graded Approach to Safety Criteria .......................................................................................... 29 8.0 Potential Organizational and Process Changes ......................................................................... 31 9.0 Implications for RPS.................................................................................................................... 33 10.0 Summary of Conclusions and Recommendations ..................................................................... 35 Appendix A Study Group Members ................................................................................................... 38 Appendix B Exclusion of Cold Uranium Fuel from Approval Process ........................................... 40 iii List of Figures Figure 3-1. The U.S. safety review and launch approval process for nuclear-powered space missions.
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