 Other nuclear power incidents within the US (defined as safety-related events in civil nuclear power facilities between INES Levels 1 and 3 include those at the Davis-Besse Nuclear Power Plant, which was the source of two of the top five highest conditional core damage frequency nuclear incidents in the United States since 1979, according to the U.S. Nuclear Regulatory Commission.Despite the concerns which arose among the public after the Three Mile Island incident, the accident highlights the success of the reactor's safety systems.The radioactivity released as a result of the accident was almost entirely confined within the reinforced concrete containment structure.