1. EC/IAEA/ISOE Workshop Portoroz Slovenia April 2002 Electronic Personal Dosimetry Presented by Andy Weeks

2. Page 25346 Personal Electronic Dosimetry UK Regulatory Framework For Dosimetry Service Approval Clients of the Service Operation of the Service Summary of Performance The Future

3. Page 35346 UK Regulations Governing the Approval of Dosimetry Services UK Health and Safety at Work Act 1976 Ionising Radiations Regulations 1999. (IRR) Basis Safety StandardsICRP 60 EURATOM Directives

4. Page 45346 UK IRR’s Governing the Approval of Dosimetry Services Regulation 35 - Enables Health and Safety Executive (HSE) to approve suitable dosimetry Services for some or all of the following : Regulation 21 - Routine assessment and record keeping for classified persons. Regulation 23 - Accident dosimetry. Regulation 12 - Provision of dosemeters or other devices for contingencies.

5. Page 55346 Dosimetry Services Clients. l Clients are made up of UK operational and decommissioning reactor sites. l British Energy Generation Ltd l 5 operating AGR reactor sites and 1 PWR. l British Nuclear Fuels plc (BNFL) l 5 operating Magnox reactor site. l 5 decommissioning Magnox reactor sites.

6. Page 65346 Dosimetry Services Clients. Approval Status l 5 Operating sites fully approved by HSE. l 7 Sites with approvals pending l 4 Sites processing applications.

7. Page 75346 Siemens - Electronic Personal Dosemeter (EPD)

8. Page 85346 Siemens - Access Control Workstation

9. Page 95346 Typical Site Hardware Requirements Average EPD's per site - 100-200 Average During Outage - 400 (Peak on some site 600) Average Number of ACW's per site 4 - 7 3- 6 for Controlled Area Access 1 for Training / Spare 1 File Servers per site 2 held centrally as hot spares

10. Page 105346

11. Page 115346 Central Approved Assessment Service Demonstrates Independence from the employer Self issue and return of EPD Secure database on client LAN to accommodate ADS Data Legal dose assessment performed by summation of working session and manually assessed doses Working Sessions doses (a few minutes to several hours) recorded with personal details to Secure ADS database The BNFL EPD Approved Dosimetry Service

12. Page 125346 Client Sites to demonstrate compliance with ADS Statement of Service Client sites to provide ADS with Operating Manual and systems of work for EPD dosimetry on their site Demonstrable audit trail for transfer of information from EPD to ADS Quality Assurance

13. Page 135346 Quality Assurance Clients systems and documentation audited by the ADS. Audit report submitted to Health and Safety Executive (HSE) with application to become a client of the ADS HSE will visit Client site before approval is given New certificate of approval issued to the ADS for each new client.

14. Page 145346 Common Corrective Actions Recording of Training Specific Work instructions. External Courses and generic Training Packages Systems for dealing with Computer failure. Manual Entry Systems. Disaster recovery. Interaction with other internal service providers. IT department providing computer back-up services.

15. Page 155346 EPD Diagnostics Ability to recalculate dose from raw data Ability to identify spurious doses caused by e.g.:- Non ionising radiation. (e.g. RFI) Drops EMC interference

16. Page 165346 EPD Diagnostics Siemens EPD has 3 detectors Counts registered in 4 channels Hard Gamma (HG) Soft Gamma (SG) Beta (B) Beta Compensated (BC) Ratios of Channels (HG/SG) (SG/B) and (B/BC) give indication of problems from spurious doses.

17. Page 175346 EPD Diagnostics EPD counter Ratios - HG/SG

18. Page 185346 Management of Dose Estimates Manual Amendments. Amendments made due to EPD Failure for example physical damage or battery Failure. Site Amendments. Amendments made by the site due to spurious doses caused for example by RFI, electrostatic conduction or light leakage through the beta window. ADS Amendments. Anomalous doses identified by the Services diagnostics software.

19. Page 195346 Dose Amendments for 2001

20. Page 205346 Oldbury-on-Severn Power Station

21. Page 215346 Summary of Performance Application for approval submitted to HSE February 1997 First Certificate of approval January 2000. Oldbury Power Station first Client June 2000 By 31/12/2002 Service will have 16 Clients. Enabled Client sites to control doses to much lower levels Significant improvement in statistical uncertainties in calculating site and group collective dose statistics. Has proved to be cost affective due to reduced manpower requirements for Service and Clients.

22. Page 225346 Summary of Performance EPD Mk 1.2 Performs well in all radiological environments encountered on nuclear power plants. Access control Work Stations and computer systems very reliable and robust. EPD not as reliable as expected circa 20% return rate for repair. (compared to Hinkley Point Mk 2 EPD’s at circa 2%) Sensitivity to RFI, EMC, etc irritating. Poor battery performance.

23. Page 235346 The Future Application to be made to the UK Health and Safety Executive for the Mk 2 EPD during 2002. First Client will be British Energy Hinkley Point B Power Station (AGR) During financial year 2003 /2004 BNFL will consider a project to upgrade from Mk 1.2 EPD to Mk 2EPD.

24. EC/IAEA/ISOE Workshop Portoroz Slovenia April 2002 Electronic Personal Dosimetry