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IMPACT ON RADIOLOGICAL BARRIERS AND CONTROLS AT FACILITIES
Radiological barriers and controls

WHY HAVE THESE CRITERIA CONTINUED...

 

Similarly, a large contamination spread would certainly be perceived publicly as a significant event

But...

with no release outside the facility
and no problems with the main safety systems

... the event would only be rated at Level 1

That was why INES was designed with an additional set of criteria that would recognize the significance of accidents like TMI and major spreads of contamination.