Civil Engineering Reference
In-Depth Information
Fig. 9.13
International nuclear event scale [
22
]
Level 0: Deviation
- Classifies: Deviations of no safety significance, e.g. leakage from a primary
coolant circuit
Level 1: Anomaly
- Classifies: impact on the defense in-depth, e.g. damaging of a fuel element
during unloading process
Level 2: Incident
- Classifies: impact on radiological barriers, on people or environment,
e.g. radiation levels in an operating area of more than 50 mSv.
Level 3: Serious incident
- Classifies impact on radiological barriers, on people or environment,
e.g. radiation levels in an operating area of more than 1 Sv/h.
Level 4: Accident with local consequences
- Classifies: impact on radiological barriers, on people or environment, e.g. SL-1
accident (USA). Experimental reaction SL-1 reached prompt criticality killing
three operators.
Level 5: Accident with wider consequences
- Classified: impact on radiological barriers, on people or environment,
e.g. Windscale accident in the United Kingdom in 1957, Three Mile Island
Accident near Harrisburg (USA) in 1979.
