Intervention Levels and Measures

Some of the most important measures to be taken immediately after a nuclear accident include sheltering and iodine prophylaxis with tablets of stable potassium iodine. Different countries use different intervention levels for these measures. Intervention policy in Austria tends to be more cautious and uses lower dose levels than Germany or the IAEA recommendations, while Germany has lower levels for pregnant women.

		Austria (IntV 2007), in mSv	Germany (SSK 2008), in mSv	IAEA (IAEA 2011), in mSv
Sheltering	Children, pregnant women	1	10	100 for fetuses
	Adults	10	10	100
Iodine prophylaxis	Children	10	50	50
	Prgenant women	100	50
	Adults up to 40 years	100	250	50 (former recommendation: 100 avertable dose)
	Adults over 40 years	500	Adults over 45 years should not take the iodine tablets at all

Agricultural intervention measures

If a contamination of ground and air beyond certain thresholds can be expected, a set of agricultural intervention measures is triggered. These measures include earlier harvesting, closing of greenhouses and covering of plants, putting livestock in stables etc.

For these measures, Austria and Germany defined the following levels (AG Proben 2010, SSK 2008b):

Nuclide	Deposition in kBq/m2	Time-integrated concentration in air in Bq s/m3
Cs-137	0.65	1.3E6
I-131	0.70	6.1E5

These agricultural measures are quite complex and take some time. Reactions are especially difficult if there is only very little time between the onset of an accident and the arrival of the first radioactive clouds.

For very high contaminations - above a level of about 7,000 MBq Cs-137/m² - agriculture can be no longer be sustained and the areas will probably have to be afforestated (SSK 2008b).