Nuclear Energy and Nuclear Disasters. "An unexpected event involving nuclear weapons that results in any of the following: (1) Accidental or unauthorized launching, firing, or use by U.S. Forces (2) U.S.-supported allied forces of a nuclear-capable weapons system. (3) An accidental, unauthorized, or unexplained nuclear detonation. (4) Non-nuclear detonation or burning of a nuclear weapon. (5) Radioactive contamination. (6) Jettisoning of a nuclear weapon. (7) Public hazard, actual or perceived". (DoD, DoD Response to Radiological Accidents, 1996, p. 9)