INES-event
INES 1

ROUTINE SURVEILLANCE REVEALS: STEAM GENERATOR SAFETY VALVES OPEN AT HIGHER PRESSURE THAN SPECIFIED AT THE RINGHALS 2. 3 AND 4 PWRS

During routine testing of Unit 2 the safety valve on a steam generator opened at solmewhat higher pressure than specified. Similar failures were detected at the other steam generators and also at Unit 3 and 4.
Justification of rating:
Degradation of defence in depth without initiator
Safety function availability: Adequate
Initiator frequency/initiator probability: Medium/possible

Location: RINGHALS-2
Event date: Sun, 28-05-1995
Nuclear event report
Legenda & explanation