The IAEA has issued a new publication in its Emergency Preparedness and Response Series on ‘operational intervention levels for reactor emergencies and methodology for their derivation’.

Operational Intervention Levels (OILs) are operational criteria that allow decision-makers to promptly implement protective actions and other response actions on the basis of monitoring results available during a nuclear or radiological emergency. As an example, following a severe release of radioactive material from a nuclear power plant, it may be necessary to promptly implement restrictions on the consumption and trade of certain local produce such as wild-grown products and milk from grazing animals. This publication provides the criteria to implement?these protective actions, based on simple and reliable ambient gamma dose rate monitoring results, thus ensuring a faster and more effective protection of the public.

The use of OILs as part of the protection strategy is required by “Preparedness and Response for a Nuclear or Radiological Emergency” (IAEA Safety Standards Series No. GSR Part 7). This publication will assist IAEA Member States in meeting the requirements for deriving pre-established (default) OILs and contribute to the harmonization of national criteria for implementing protective actions and other response actions, a need emphasized by the IAEA General Conference in resolution GC(55)/RES/9 and highlighted in resolution GC(56)/RES/9.

This new publication provides numerical values of pre-established (default) OILs, a detailed description of the methodology for deriving IAEA's default OIL values, as well as practical tools and recommendations for their use. It includes a CD with the spreadsheets used in the calculations of OILs, which is intended to facilitate the application of the methodology and/or revision of the OILs by IAEA Member States adopting them for national application.