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SCALE Code System

The SCALE code system is a widely used modeling and simulation suite for nuclear safety analysis and design that is developed, maintained, tested, and managed by ORNL’s Reactor and Nuclear Systems Division (RNSD) and deployed to over 9,000 users in 59 nations. SCALE provides a comprehensive, verified and validated, user-friendly tool set for criticality safety, reactor physics, radiation shielding, radioactive source term characterization, and sensitivity and uncertainty (S/U) analysis. Since 1980, regulators, licensees, and research institutions around the world have used SCALE for safety analysis and design. The NRC is the primary
sponsor of SCALE for its application in licensing current and advanced reactors, fuel cycle facilities, and radioactive material transportation and storage. An additional 33 international regulatory bodies are included in the thousands of SCALE users.

SCALE provides a modern, integrated framework with dozens of computational modules, including four deterministic solvers and three Monte Carlo radiation transport solvers from which the user selects based on the
desired solution strategy. SCALE includes current nuclear data libraries and problem-dependent processing tools for continuous-energy (CE) and multigroup (MG) neutronics and coupled neutron-gamma calculations, as well as activation, depletion, and decay calculations. SCALE provides unique capabilities for automated variance reduction in shielding calculations, as well as S/U analysis. SCALE’s graphical user interfaces (GUIs) assist with accurate system modeling and provide convenient access to desired results. SCALE 6.2 is one of the most comprehensive revisions in the history of SCALE, providing several new capabilities and significant improvements in many existing features.

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Licensing: SCALE 6.2.3 is available from RSICC, NEA, and RIST as package C00834.