title: Nuclear criticality accidents.
abstract: Criticality occurs when a sufficient quantity of fissionable material is accumulated, and it results in the liberation of nuclear energy. All process accidents have involved plutonium or highly enriched uranium, as have most of the critical experiment accidents. Slightly enriched uranium systems require much larger quantities of material to achieve criticality. An appreciation of criticality accidents should be based on an understanding of factors that influence criticality, which are discussed in this article.
authors.affiliation: Los Alamos National Laboratory, New Mexico.
authors.forename: D R
authors.initials: DR
authors.lastname: Smith
mesh_terms: D000062:Accidents, Occupational; D009688:Nuclear Reactors; D014481:United States