1. Origin of the rules

Today, France's nuclear reactor fleet meets around 80% of the country's electricity needs. It was the result of a strong political will in the early 1970s, in response to the first oil crisis. After the initial Franco-Belgian experiments with the Chooz A plant and the commitment to Tihange-1, the pressurized water reactor (PWR) option was chosen in December 1970 for the Fessenheim plant, then confirmed first for the Bugey plant, then definitively for the subsequent 900 and 1,300 MWe units.

Building these plants under U.S. license meant referring to U.S. rules and codes, which had to be adapted to the French and then European industrial context.

The development of the nuclear industry in the United States was accompanied by a major regulatory effort in the field of nuclear safety, complementing an already rich body of construction codes and...