 Some observers have condemned the referendum as flawed because people could only vote "NO to nuclear", although three options were basically a harder or a softer "NO".After the 1986 Chernobyl accident in USSR, the question of security of nuclear energy was again raised.In July 1992 an incident at Barsebäck 2 showed that the five older boiling water reactors had had potentially reduced capacity in their emergency core cooling systems since they started operation.