France's nuclear safety regulator, the Autorité de Sûreté Nucléaire (ASN), has set the conditions for the continued operation of EDF's 900 MWe reactors beyond 40 years. EDF operates thirty-two 900 MWe reactors which came into commercial operation between 1977 and 1988. Some of them are the oldest in the country's current nuclear fleet. According to the regulator, the measures planned by EDF, combined with those prescribed by the ASN, will ensure the safety of the units for a further 10 years of operation.