2. Formalizing the concept of defense in depth in the nuclear industry

Initially used in the military to protect territory and strongholds, the concept of defense in depth was applied to civil nuclear power in the 1960s, with the aim of formalizing plant safety policy in the USA, and later in other nuclearized countries. The aim of this concept is to protect personnel, the population and the environment against the release of radioactive materials outside the reactor or plant. As Jacques Libmann points out , "the concept of defense in depth is not a guide for examining a facility associated with a particular technical solution such as a staging of particular barriers, but a method of reasoning...