Eleven percent of the world's supply of electricity is generated by 450 commercial nuclear power reactors in 31 nations with 60 new reactors currently under construction.

Nuclear science and research to develop these nuclear power capabilities requires a wide range of effects to be considered for the design, regulation, development, and operation of these systems. Modeling and simulation with verified and validated software and data offers a cost-effective and important tool for analyzing many aspects of nuclear technology using a scientific and engineering basis for decision making in the industry. SCALE is a comprehensive modeling and simulation suite for nuclear safety analysis, and is design developed and maintained by Oak Ridge National Laboratory (ORNL). This code system is a verified and validated, user-friendly tool set for criticality safety, reactor physics, radiation shielding, radioactive source-term characterization, sensitivity and uncertainty analysis, and nuclear data library generation, with significant new capabilities included in the 2016 deployment of SCALE 6.2.

The distribution of SCALE to end-users is subject to U.S. export control regulations, and each user must be individually licensed through an authorized distribution center.

SCALE licenses are primarily issued through the Radiation Safety Information Computational Center (RSICC) at ORNL with mirrors at the Organization for Economic Cooperation and Development (OECD) Nuclear Energy Agency (NEA) Data Bank in France and the Research Organization for Information Science and Technology (RIST) in Japan. SCALE 6.2 was released in April 2016, and through June 2018 there have been over 4,000 licenses issued to users in 42 nations, including nearly 1,500 distributions to new users.

As of June 2018, there are nearly 9,000 individuals in 58 nations licensed for one or more versions of SCALE. SCALE is an essential tool to many in the nuclear industry, where engineers use SCALE on a daily basis for analysis and design. The developers and expert users from the SCALE team support licensees by providing training that has included over 20 weeklong courses on SCALES 6.2 presented 400 participants from 15 nations.