1. 1 PASSIVE DOSIMETER BENCHMARKING

2. 2 CONTEXT French regulations originally required film to be used as a passive dosimeter. The decision dated 23 rd March 1999 does not impose any particular technology. Technological advances have made the future of film uncertain. In early 2001 the Management at the EDF Group’s Nuclear Generation Division decided to undertake a study : feasibility and potential benefits of adopting a new passive dosimeter technology.

3. 3 VARIOUS TECHNOLOGY AVAILABLE Film dosimeter TLD : ThermoLuminescent Dosimeter OSL : Optically Stimulated Luminescence dosimeter RPL : RadioPhotoLuminescent dosimeter

4. 4 STUDY PLAN 2001 : State of the art of the various technologies available and experience feedback 2002 : Comparative study of the behaviour of the different technologies under laboratory conditions and real situations in 3 EDF nuclear power plants over 3- month period Early 2003 : Survey of international nuclear operators conducted via the ISOE network

5. 5 COMPARATIVE TRIALS Around 250 badges including Film, TLD, OSL and RPL worn by a specific group of personnel, selected according to exposure conditions  High exposure : Maintaining the reactor building (cleaning, decontamination) Installing and removing nozzle dam inside steam generators water box Valve mechanics, insulation technicians and welders working on primary and connected circuits  Low exposure : Chemists Business managers and foremen RPS (radiation protection service) technician Fuel disposal Sorting radioactive waste

6. 6 COMPARATIVE TRIALS Identical badges were tested in extreme conditions : ›Exposure to 20 mGy for 1 minute (gamma radiography projector) ›Exposure to 4.4 mGy for 11 minutes (filter in the process) ›Exposure through an X-ray detector machine ›Poor thermal conditions with temperatures reaching 70°C The results are consistent, and the deviations observed are in line with standards. The technical performances of the OSL and RPL dosimeters are quite similar, and often superior to those of film and TLD EDF – Research and Development will be issuing a publication

7. 7 RESULTS OF COMPARATIVE STUDY CharateristicsFilmTLDOSLRPL Technical Aspects Dose dynamic-=++ Dose linearity-=+++ Energy response-=+++ Repetition-=++ Batch uniformity-++++ Influence quantity-=+++ RegulationsDose storage++- = Economic Aspects Number of suppliers+++-- Market - Carries=++- Operating cost+-+- SUMMARY-=+++ -Acceptable= Medium+ Good++ Very good

8. 8 CONCLUSION OSL combines the various benefits of Film, TLD and RPL The DPN Management decided to replace film with OSL in 2 pilot nuclear plants to the period July 2004 to December 2005 and in all plants in 2006 European call for tender published in september 2003 for the period July 2004 to December 2005