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IMPACT ON PEOPLE AND THE ENVIRONMENT
Release

WHY STOP AT LEVEL 4?

 

There are two main reasons why only events rated as accidents (Levels 4 to 7) are evaluated based on the quantity of radioactive material released:

Perhaps the most important is that events at Levels 4–7 are termed accidents and below Level 4 are termed incidents.

It is difficult to explain to the public and media, or even to technical people, that events that meet criteria for large releases are only termed incidents!

The second is that releases less than those for Level 4 will probably not require evacuation or sheltering and, therefore, dose criteria is a good measure of the significance of the event.