1Examples of other response actions include the provision of public information, medical treatment and long term health monitoring.

2A manual for assessment of field data in a nuclear or radiological emergency is in preparation.

3A deterministic effect is considered to be a severe deterministic effect if it is fatal or life threatening or if it results in a permanent injury that reduces quality of life [2, 5].

4See Appendix I.

5Medical actions should be initiated and performed on the basis of medical symptoms and observations. However, dosimetric information (e.g. based on radiation survey data, dose measurements or dose calculations) can provide a valuable input for determining the medical treatment.

6These operational criteria are used as ‘triggers’ at the early stage of an emergency, and in some publications the term ‘trigger’ is used.

7Threat categories I, II and III represent decreasing levels of threat at facilities and of the corresponding stringency of requirements for emergency preparedness and response arrangements. See para. 3.6 and table I of Ref. [2] for more details.

8A dangerous source is a source that could, if not under control, give rise to exposure sufficient to cause severe deterministic effects. This categorization is used for determining the need for emergency response arrangements and is not to be confused with categorization of sources for other purposes.

9The Papanicolaou test.

10Instructions will cover the application of time, distance and shielding principles, the prevention of ingestion of radioactive material and the use of respiratory protection.

11These operational criteria are used as triggers at the early stage of an emergency; in some publications the term ‘trigger’ is used.

12OILs for rates or air concentrations in a plume resulting from an ongoing release are not provided because the example criteria are intended to be very general and practical. OILs for air doses or air concentrations from a plume are not included because: (a) in many cases the significant release will be over by the time results of environmental measurements are available; (b) it is difficult to take and analyse air concentrations in a sample in a timely manner; (c) there is a great variation in time and location of the plume concentrations at any location during a release; and (d) OILs of these types are highly dependent on the nature of the release, which makes it very difficult to develop OILs that apply to the full range of possible releases. During the period of significant release, therefore, protective actions (e.g. evacuation or sheltering, to a predetermined distance) are best taken on the basis of observable criteria. Operating organizations of facilities at which there could be emergencies that result in airborne releases of long duration should develop EALs and possibly facility specific OILs for measurements taken in a plume, for possible airborne releases from the facilities. Examples of OILs for dose rates in a release from a light water reactor resulting from core melt are provided in Ref. [27].

13OILs for air concentrations arising from resuspension are not provided because doses arising from resuspension have been considered in the deposition OILs.

14In the response to the Chernobyl accident in 1986, in some cases ⁴⁰K was confused with ¹³⁷Cs and produce was discarded even though it contained virtually no radioactive caesium [31].

15Restriction of the consumption of essential food could result in severe health effects (e.g. severe malnutrition).

16Examples of events that should not be included in the emergency classification system are: technical deficiencies exceeding the limits of in-service inspection codes; equipment failure beyond expected reliability limits; detection of major design deficiencies or of potential accident sequences outside the plant’s design basis; symptoms of severe deficiencies in operator training or behaviour; breaches of technical specifications or of transport regulations; and deficiencies in safety culture.

17‘Projected damage’ is indicated by a loss of critical safety functions necessary to protect the core or large amounts of recently discharged fuel.

18The dropping of a fuel transport container and a fuel handling accident are considered facility emergencies because they cannot give rise to doses that warrant protective actions off the site.

19Examples of EALs for a facility emergency are not included because research and generic studies have not been done to identify the range of possible facility emergencies that could be used as a firm basis for developing such examples. Events that are classified as a facility emergency and EALs for their classification should therefore be based on site specific analysis.

20Severe damage resulting in a release of greater than 20% of the gap inventory.