In 2005, ICRP Publication 96 set out guidelines for protecting people against radiation exposure in the event of a radiological attack. Since then, ICRP has updated its fundamental recommendations in Publication 103 and also produced Publication 146 giving advice on protecting people and the environment in the event of a large nuclear accident. This leaves an important gap in the advice offered by ICRP for radiological emergencies that are not large-scale nuclear accidents. Furthermore, some of the basic concepts/approaches described in Publication 96 have been superseded by the 2007 recommendations, so the advice currently offered by ICRP for malicious events is not as consistent or comprehensive as it should be.
To remedy this situation, a Task Group is needed to consider updating and broadening the scope of Publication 96 to include small and medium scale radiation emergencies. These will include but are not limited to transport accidents, fires and other events causing damage to sites holding radioactive materials, and inadvertent damage to sealed sources (e.g., Windscale Fire, Kyshtym, Goiania and Tokaimura accidents). Malicious use of radioactive materials will include the targeted poisoning of individuals, radiological dispersal devices, theft of radioactive materials and radiopharmaceuticals from facilities or during transport, covert radiological exposure devices, deliberate contamination of food and water supplies, and sabotage of nuclear facilities. Non-radiological aspects of response to, and recovery from events will be considered to ascertain implications for application of ICRP recommendations. For all scenarios, a graded approach to protection will be taken, with the aim of making the advice as generally applicable as possible, accepting that specific guidance may be required for some distinctive aspects. Guidance on managing each specific type of scenario, if necessary, may be presented as an Annex of the report. Improvised nuclear devices are considered to be out of scope.
The System of Radiological Protection has evolved since Publication 96, from the previous process-based approach using practices and interventions to a single, consistent approach based on optimisation of protection with the use of appropriate individual dose criteria for all exposure situations and categories of exposure. The updated report will provide guidance for managing exposures from radiation emergencies and malicious events, elaborating the radiological protection framework for emergency and existing exposure situations, as appropriate. Exposures of plants and animals in the environment, not previously included, will now be considered alongside public exposures, in keeping with an integrated approach to radiological protection. Special consideration will be given to radiological protection advice for emergency and recovery responders, based on the approach adopted in Publication 146.
Furthermore, a complete overhaul of the radiological protection criteria used in Publication 96 is required. Intervention levels, expressed in terms of avertable dose, were used previously for the introduction of urgent protective actions, whilst longer term protective actions were implemented according to dose criteria recommended in Publication 82. The updated report will replace these criteria with Reference Levels (residual effective dose) for optimising protection during the planning and implementation of protective actions in both emergency and existing exposure situations. The previous inclusion of derived criteria (Bq/kg and Bq/l) for a wide range of radionuclides in commodities, food and drinking water is now provided elsewhere (i.e. IAEA, Codex and WHO) and need not be specified in this report. Other areas worthy of inclusion include termination of protective actions; management of waste; wider ranging stakeholder engagement including law enforcement and nuclear forensics agencies; management of businesses; health surveillance; and communication. Unnecessary repetition of information contained in Publication 146 will be avoided. Furthermore, for medical interventions and decontamination of people, as well as security arrangements for preventing malicious events, referencing to recent authoritative publications on the topic may be appropriate.
In terms of structure, the report could follow that adopted in Publication 146 with three main sections encompassing ‘general considerations’, ‘early and intermediate phases’ and ‘long-term phase’. This would enable cross-cutting topics such as timeline, consequences (i.e., radiological and non-radiological health effects), principles for protection of people and the environment to be included without excessive repetition. It would also enable radiological criteria and protective actions, relevant to emergency exposure situations and existing exposure situations, to be introduced separately. This would additionally address the inconsistent nomenclature around ‘response phases’ described in Publication 96.
The Task Group will develop ICRP recommendations for radiological protection for small and medium scale radiation emergencies and malicious events. These recommendations will complement those given in Publication 146 for large nuclear accidents. In doing so, the Task Group will:
The Task Group will prepare a report for publication in Annals of the ICRP, outlining radiological protection advice for people and the environment following small to medium scale radiation emergencies and malicious events. The report will complement Publication 146 without unnecessary repetition and close the current ‘gap’ in advice for small to medium scale emergencies. The Task Group may consider publication of peer review literature articles during the development of the report, including workshop discussion summaries.
In addition, the Task Group will develop materials suitable for ICRPÆDIA in collaboration with the Scientific Secretariat.
|Anne Nisbet (Chair), Public Health England, United Kingdom|
|Peter Bryant (Member), University of Surrey , United Kingdom|
|Chunsheng Li (Member), Health Canada, CANADA|
|Jennifer Mosser (Member), EPA, USA|
|Shogo Takahara (Member), JAEA, Japan|