[en] In the world, only two serious accidents occurred in nuclear power plants: Harrisburg (Three Miles Island) in Usa in 1979 and Chernobyl in Ussr in 1986. In the two cases there was a reactor core meltdown. By the different conception of the reactors, the human consequences were null in the first case and very important in the second one. The nuclear power plants in France have been build on the Harrisburg type (PWR type reactors). But the nuclear safety and the civil safety have to be continuously improved. The possibility for the population to find iodine tablets is an additional safety. (N.C.)