
U.S. Nuclear Regulatory Commission

Home

Who We Are

What We Do

Nuclear Reactors

Nuclear Materials

Radioactive Waste

Facility Info Finder

Public Involvement

Electronic Reading Room

Beyond design-basis accidents

This term is used as a technical way to discuss accident sequences that are possible but were not fully considered in the design process because they were judged to be too unlikely. As the regulatory process strives to be as thorough as possible, “beyond design basis” accident sequences are analyzed so as to fully understand the capability of a design.