Methodological aspects of the ICRP recommendations implementation

1. Methodological aspects of the ICRP recommendations implementation Wolfgang Raskob

2. Task • In the frame of the Collaborative European research project NERIS-TP, a work package has to deal with adaptation of simulation models to the new recommendations (ICRP, BSS) • Within the NERIS Platform a working group was established to support that activity • This workshop should provide further input • Why do we need that input?

3. Countermeasures: status • So far intervention criteria (country specific) exist for individual countermeasures such as for Germany • sheltering (10 mSv in 7 days from all exposure pathways, except ingestion) • evacuation (100 mSv in 7 days from all exposure pathways, except ingestion) • Iodine distribution (50 mSv thyroid dose by iodine for children, 250 mSv thyroid dose for adults) • relocation (100 mSv in 1 year from ground exposure) • Food intervention levels (concentrations)

4. New ICRP proposal • With the ICRP recommendations 103, 109 and 111, new concepts and quantities have been introduced into emergency management and rehabilitation • The concept of a “reference level” for emergency and existing controllable exposure situations that represents the level of dose or risk, above which it is judged to be inappropriate to plan to allow exposures to occur, and for which therefore protective actions should be planned and optimised • When deciding on the optimum course of protective actions, all exposure pathways and all relevant actions have to be taken into account

5. Consequence of ICRP • All exposure pathways have to be simulated within one simulation program • Questions • Which dose can be used for the evaluations? • Open air • Normal living • Which endpoint/starting point to be considered? • Residual dose in the first year, taking into account all exposure pathways • Calculate for “trigger” values that might be also measurable quantities • Short term triggers and long lasting scenarios? • Can we stay with the existing framework of individual intervention criteria and assure that we always stay below the residual dose limit

6. Consequence of ICRP • Questions continued • Is there a need for more than one reference level, dependent on the threat? • How to define the dose criteria for the lifting of measures? • Is there a need for defining such values or should this be a point for discussion with stakeholders? • Use of a dose range? • Is the dose from ingestion part of the initial calculations? • Assuming the existing maximum permissible levels, the dose from food might contribute only by 10 mSv in a year • Do we have to consider critical groups • What’s about optimisation? • Same model or different model? • Part of the initial strategy or simulated separately?

7. Consequence of ICRP • Questions continued • How to support optimisation? • Is this a task of an expert or can a DSS provide guidance in this? • Do we need specific tools to perform scenario calculations to define appropriate strategies? • Has a country resources to define default strategies for each threat? • Can we trace/understand the results of complex simulations? • What are the end points that should be included? • Is “distribution of iodine tablets” an individual measure or part of a strategy? • Is there a clear understanding of the applications of measures in terms of strategies? • Sheltering in favour of evacuation • Evacuation in favour of relocation

8. Answers • First ideas are provided in the talk by Claudia Landman

9. Thank you very much for your attention Question?