IDEAS / IAEA Intercomparison Exercise on Internal Dose Assessment OPEN REPORT SCK•CEN-BLG-1018 IDEAS / IAEA Intercomparison Exercise on Internal Dose Assessment Intercomparison exercise on Internal Dose Assessment performed jointly by the International Atomic Energy Agency and the IDEAS project (“General Guidelines for the Evaluation of Incorporation Monitoring Data”, carried out within the 5th EU Framework Programme). C. Hurtgen, A. Andrasi, M.R. Bailey, A. Birchall, E. Blanchardon, V. Berkovski, C.M. Castellani, R. Cruz- Suarez, K. Davis, H. Doerfel, B. LeGuen, I. Malatova, J. Marsh, J. Zeger October, 2005 SCK•CEN Boeretang 200 2400 Mol Belgium OPEN REPORT OF THE BELGIAN NUCLEAR RESEARCH CENTRE SCK•CEN-BLG-1018 IDEAS / IAEA Intercomparison Exercise on Internal Dose Assessment IDEAS / IAEA Intercomparison Exercise on Internal Dose Assessment Intercomparison exercise on Internal Dose Assessment performed jointly by the International Atomic Energy Agency and the IDEAS project (“General Guidelines for the Evaluation of Incorporation Monitoring Data”, carried out within the 5th EU Framework Programme). C. Hurtgen, A. Andrasi1), M.R. Bailey2), A. Birchall2), E. Blanchardon3), V. Berkovski4), C.M. Castellani5), R. Cruz- Suarez6), K. Davis2), H. Doerfel7), B. LeGuen8), I. Malatova9), J. Marsh2), J. Zeger6) 1)KFKI-AERI, Budapest, Hungary 2)HPA, Chilton Didcot, United Kingdom 3)IRSN, Fontenay-aux-Roses, France 4)RPI, Kiev, Ukraine 5)ENEA, Bologna, Italy 6)IAEA, Vienna, Austria 7)FZK, Karlsruhe, Germany 8)EDF-GDF, Saint-Denis, France 9)NRPI, Praha, Czech Republic October, 2005 Status: Unclassified ISSN 1379-2407 SCK•CEN Boeretang 200 2400 Mol Belgium IDEAS / IAEA Intercomparison Exercise on Internal Dose Assessment © SCK•CEN Belgian Nuclear Research Centre Boeretang 200 2400 Mol Belgium Phone +32 14 33 21 11 Fax +32 14 31 50 21 http://www.sckcen.be Contact: Knowledge Centre [email protected] RESTRICTED All property rights and copyright are reserved. Any communication or reproduction of this document, and any communication or use of its content without explicit authorization is prohibited. Any infringement to this rule is illegal and entitles to claim damages from the infringer, without prejudice to any other right in case of granting a patent or registration in the field of intellectual property. SCK•CEN, Studiecentrum voor Kernenergie/Centre d'Etude de l'Energie Nucléaire Stichting van Openbaar Nut – Fondation d'Utilité Publique - Foundation of Public Utility Registered Office: Avenue Herrmann Debroux 40 – B-1160 Brussel Operational Office Boeretang 200, 2400 Mol, Belgium IDEAS / IAEA Intercomparison Exercise on Internal Dose Assessment IDEAS / IAEA Intercomparison Exercise on Internal Dose Assessment ABSTRACT There were several intercomparison exercises organized already at national and international levels for the assessment of occupational exposure due to intakes of radionuclides. These intercomparison exercises revealed significant differences in the approaches, methods and assumptions, and consequently in the results. In the frame of the IDEAS project “General Guidelines for the Evaluation of Incorporation Monitoring Data”, launched in the 5th EU Framework Programme, a new intercomparison exercise was performed. Originally it was planned to organise this intercomparison exercise on a European scale. Because of the relevance of the issue for the whole community of internal dosimetrists, however, it was decided to organise the exercise on a broader scale together with the IAEA. This new intercomparison exercise especially focuses on the effect of the guidelines for harmonisation of internal dosimetry. In addition it also consider the following aspects: • to provide possibilities for the participating laboratories to check the quality of their internal dose assessment methods in applying the recent ICRP recommendations (new respiratory tract model etc.), • to compare different approaches in interpretation of internal contamination monitoring data, • to quantify the differences in internal dose assessment based on the new guidelines or on other procedures, respectively, • to provide some figures of the influence of the input parameters on the monitoring results and • to provide a broad forum for information exchange. Several cases have been selected for the exercise with the aim to cover a wide range of practices in the nuclear fuel cycle and medical applications. The case were: 1. Acute intake of HTO 2. Acute inhalation of fission products 137Cs and 90Sr 3. Intake of 60Co 4. Repeated intakes of 131I 5. Intake of enriched uranium 6. Single intake of Pu radionuclides and 241Am A web-based approach was being used for the presentation of the cases, collection of responses and potential discussion of the results. Solutions to these cases were reported by 80 participants worldwide. This report presents and discuses the main findings and recommendation for future actions. Page i IDEAS / IAEA Intercomparison Exercise on Internal Dose Assessment Table of contents : 1. INTRODUCTION..............................................................................1 1.1. Background....................................................................................................1 1.2. State of the art ................................................................................................1 1.3. General requirements.....................................................................................2 2. THE IDEAS PROJECT ....................................................................4 2.1. Development of the General Guidelines........................................................4 2.2. The IDEAS Guidelines for Evaluation of monitoring data ...........................5 2.2.1 Introduction............................................................................................5 2.2.2 Level of task...........................................................................................6 3. PRACTICAL TESTING OF THE GENERAL GUIDELINES....8 3.1. Objectives ......................................................................................................8 3.2. Scope..............................................................................................................9 3.3. Schedule.........................................................................................................9 3.4. Participation .................................................................................................10 3.5. Procedure for selecting data for statistical evaluation .................................11 4. Case 1: ACUTE INHALATION OF HTO ....................................13 4.1. Case description...........................................................................................13 4.1.1 The event..............................................................................................13 4.1.2 Additional information.........................................................................13 4.1.3 Body monitoring data..........................................................................14 4.1.4 Excretion monitoring data....................................................................14 4.1.5 Personal Data.......................................................................................16 4.1.6 Other comments relevant for intake and dose estimation....................16 4.2. Assessment of case ......................................................................................16 4.2.1 Simple hand calculation.......................................................................17 4.2.2 Assessment according to the guidelines ..............................................18 4.3. Results of intercomparison exercise ............................................................21 4.3.1 Introduction..........................................................................................21 4.3.2 Overall distribution of results ..............................................................21 4.3.3 Identification of outliers.......................................................................26 4.3.4 Number of values used for evaluation .................................................27 4.3.5 SEE values...........................................................................................27 4.3.6 Use of guidelines..................................................................................28 4.4. Conclusion for Case 1..................................................................................28 5. Case 2: ACUTE INHALATION OF FISSION PRODUCTS......29 5.1. Case description...........................................................................................29 5.1.1 The event..............................................................................................29 5.1.2 Additional information.........................................................................29 5.1.3 Body monitoring data..........................................................................30 5.1.4 Excretion monitoring data....................................................................30 5.1.5 Personal Data.......................................................................................30 5.1.6 Other comments relevant for intake and dose estimation....................31 5.1.7 Graphic presentation of available data.................................................31 5.2. Assessment of case following IDEAS Guidelines.......................................32 5.3. Results of the intercomparison exercise