Nuclear Science


SCALE Modeling & Simulation Suite

Flexible and accurate system modeling with SCALE

SCALE is an industry-leading suite of tools for nuclear systems modeling and simulation that provides comprehensive, verified and validated user-friendly capabilities for criticality safety, reactor physics, radioactive source term characterization, radiation shielding, and sensitivity and uncertainty analysis. SCALE is developed and maintained within the Reactor and Nuclear Systems Division of ORNL with sponsorship from the US Nuclear Regulatory Commission and the US Department of Energy.

For more than 30 years, regulators, licensees, and research institutions around the world have used SCALE for nuclear safety analysis and design. SCALE provides a “plug-and-play” framework that includes three deterministic and three Monte Carlo radiation transport solvers that are selected based on the desired solution. SCALE includes the latest nuclear data libraries for continuous-energy and multigroup radiation transport as well as activation, depletion, and decay calculations. SCALE’s graphical user interfaces assist with accurate system modeling, visualization, and convenient access to desired results.

Learn more about SCALE at

For More Information, Contact:

Lead, SCALE Development and Maintenance
Brad Rearden

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