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People and the environment

The two approaches


There are two approaches to rating the significance of an event in terms of its impact on people and the environment because there are two very different types of potential accidents.

Large release of activity

The impact may be a widespread release of radioactive material from a facility, so the event could be described with

“There has been a large release of radioactivity from a nuclear power plant”

Chernobyl, 1986,

released about 1.8 million TBq 131I, 85 000 TBq Cs isotopes, 10 000 TBq 90Sr and a number of other significant isotopes

Doses to individuals

The actual impact on people and the environment may only be over a very small area, i.e. radiation doses to one or a few people close to the location of the event. For these events there is no 'release' of activity.

Goiânia, BRAZIL, 1987

Four people died and six received doses of a few gray (Gy) from an abandoned, and ruptured, highly radioactive 137Cs source.

Fleurus, BELGIUM, 2006

Severe health effects for a worker at a commercial irradiation facility as a result of high doses of radiation.

Yanango, PERU, 1999

Incident with radiography source resulting in severe radiation burns.

It could be said that the simplest approach would be to base the rating solely on the doses received, this does not necessarily give the full picture.

We're now going to look at the release criteria. If this doesn't apply to your area of application, go straight to the dose module