1. Optimization of radiation protection at Bohunice NPP
Ľubomír Dobiš
Ján Kaizer
Jaroslav Svitek

2. 4th ISOE European Workshop, Lyon, 24-26 March 2004
Introduction
Aim of the presentation:
To provide the information about the status of optimization in Bohunice NPP
Authors:
Ľubomír Dobiš – RP manager, BSS 115 qualified expert, ISOE national coordinator
Ján Kaizer – ALARA specialist
Jaroslav Svitek – head of RP section
4th ISOE European Workshop, Lyon, March 2004

3. Content of presentation
Basic Slovak RP laws
Influence of legislative requirements in NPP
Description of optimization process and tools in Bohunice NPP
Examples of optimization
Conclusion
4th ISOE European Workshop, Lyon, March 2004

4. Name Unit Operation V1 PWR, Unit 1, VVER-230 1978
PWR, Unit 2, VVER-230
1980 V2
PWR, Unit 3, VVER-213
1984
PWR, Unit 4, VVER-213
1985

5. 4th ISOE European Workshop, Lyon, 24-26 March 2004
Slovak legislation
The most important novelization of the state law No 272/94 “Protection of the People Health” by the law No 470/2000
Code of Ministry of Health No 12/2001
čo nám priniesol r. 2001?
Obdobná vyhláška v ČR SÚJB č.18497
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6. 4th ISOE European Workshop, Lyon, 24-26 March 2004
Law No 470/2000
2nd principle of radiation protection: Each person who performs the activity that leads to the exposure is obliged to ensure the magnitudes and likelihood of exposures and the numbers of individuals exposed be as low as reasonably achievable, economic and social factors being taken into account
Other requirements are transmitted to the Code
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Code 12/ §4
Technical and organizational requirements to prove the Rational Achievable Level (RAL) of radiation protection. RAL are generally proved by the comparison of the dose distribution to the costs of protection
Dose constraints
collective dose 20 man mSv for the specific task,
individual exposure 1 mSv per day
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8. 4th ISOE European Workshop, Lyon, 24-26 March 2004
Code 12/ §4 continued
Alpha coefficients are used to calculate
the benefit of the proposed measure.
Alpha cofficients
Individual exposure
2,40 mil. Sk / man Sv
less 2 mSv/y
5,96 mil. Sk / man Sv
2 – 5 mSv/y
17,86 mil. Sk / man Sv
5 – 15 mSv/y
23,82 mil. Sk / man Sv
15 – 30 mSv/y
29,77 mil. Sk / man Sv
30 – 50 mSv/y
4th ISOE European Workshop, Lyon, March 2004

9. Comparison of „α“ [man-sievert in US $]
USA (NRC)
Switzerland
Czech republic
Slovak republic – –
Source: SRS No.21, IAEA 2002, values given by the regulatory authorities
4th ISOE European Workshop, Lyon, March 2004

10. Influence of state law requirements to Bohunice NPP
Revision of plant documentation
Transparent recording of optimization in Integration Information System (IIS) Bohunice NPP
Problem solving of mathematical analysis through the collaboration with the external research institute
4th ISOE European Workshop, Lyon, March 2004

11. Revision of plant documentation
Revision of QA regulations
Defining of new terms
Optimization process
Dose constraint – result of optimization process
Target values (plant limits – ALARA criteria) – 10 manmSv, 1 mSv, 15 mSv
Revision of technological procedures
Completition of dose assessments into the procedures
4th ISOE European Workshop, Lyon, March 2004

12. ALARA flowchart Calculation of doses – dose assessment
Comparison with the ALARA criteria
Recording facts into IIS
- ALARA committee is necessary
setting the dose constraints - work on RWP
- without ALARA committee
-work on RWP
Evaluation of real exposures & feedback
ARCHIVE
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13. 4th ISOE European Workshop, Lyon, 24-26 March 2004
SW modul IIS - ALARA
Goal:
Transparent review of optimization
Instrument to help the evaluation of optimization from Radiation Work Permits after performing works
Put in operation in 2001
4th ISOE European Workshop, Lyon, March 2004

14. Integration Information System IIS- Radiation Protection part
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Optimization tools
Generation and maintenance of optimization databases
Quantitative analysis – OPTI RP
Elaboration of sensitivity analysis
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18. Database for calculation of protection cost
shielding
decontamination
waste processing
protective aids
salaries
α coefficients
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19. 4th ISOE European Workshop, Lyon, 24-26 March 2004
Comparison of the assessment of total costs-exchange of UFDSs inside SGs
year 2001: Dr=7 mGy/h, DF= year 2002: Dr=8 mGy/h, DF=7
4th ISOE European Workshop, Lyon, March 2004

20. Analysis of the assessment of costs in 2002 – exchange of UFDS
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Sensitivity analysis – exchange of UFDS - example
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22. Sensitivity analysis – exchange of UFDS - example
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23. Calculation of price of exposure (UFDS, y. 2002) - example
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24. Optimized and real exposures for exchange of UFDSs inside SGs at V-1
Dose assessment before optimization
Dose constrains for SG16 after optim.
Real doses at SG16
Dose costrains for SG26
Real doses at SG26
Collective exposure [man mSv]
101,52
57,25
86,75*
25,18
39,71*
40,55
55,11*
28,60
35,57*
Max.
Individual exposure [mSv]
8,46
4,77
3,92
4,06
3,97
Max. daily exposure [mSv]
0,564
1,04
0,92
1,00
0,99
(*) including exposures for DECONTAMINATION and positioning of Pb shielding

25. Dose management during outages
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Conclusion
Creation of transparent and understandable ALARA policy
Acceptance of optimization by workers and managers
Easy communication with the regulatory body
Optimization of RP launch to be a part of safety culture
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28. Thank you for your attention!