Current Status of Radiological Protection in NPPs of Korea 2010_ISOE_Asian ALARA Symposium Current Status of Radiological Protection in NPPs of Korea 2010. 8. 31 Byoung-il, Lee Korea Hydro & Nuclear Power Co., LTD Radiation Health Research Institute

Contents National accreditation program of radiation dosimetry system 3 NPP’s dosimetry system 3 NPP’s ALARA program 3 3 Exposure trends of NPP workers 3 RHRI’s activity for NPP’s RP

National accreditation program of radiation dosimetry system KHNP - Radiation Health Research Institute Current Status of Radiological Protection in NPPs in Korea National accreditation program of radiation dosimetry system

National accreditation program of radiation dosimetry Sys Ministry of Education, Science & Technology Korea Institute of Nuclear Safety Dose Registry Dose quality & Radiation safety control Korea Radio-Isotope Association Yearly inspection Yearly blind test with unknown TLD yearly report Internal dose Quarterly report External dose Monthly TLD reading Nuclear Power Plants Yearly blind test with unknown bioassay sample by RHRI Yearly professional training of EX/IN dose assessment by RHRI Every two reactors have a TLD reading facility and an internal dosimetry facility

Quality Assurance Manual Legislation of dose quality control – External dosimetry Routine check < 1 month Periodic check < 6 months ANSI N 13.11 [8 Criteria-blind test < 1 year] Perfor- mance Criteria Reader QC Reader < 6 months Chip < 2 years Algorithm < 6 months Calib- ration Quality Assurance Manual Technical Skills Training < 1 year Proce- dure LLD Reader quality management Reader & Chip calibration Algorithm operation Chip reading, annealing & management Management of system & document Management of person in charge Lower Limit of Detection TLD < 0.10 mSv

Legislation of dose quality control – Internal dosimetry Internal dose assessment Management of document Measurement method Workers required bioassay Internal Dosimetry legislation If unobtainable, Air sampling Bioassay Procedure Requirements of the bioassay system System operation Technical skills Surveillance and calibration Dose evaluation

Current Status of Radiological Protection in NPPs in Korea KHNP - Radiation Health Research Institute Current Status of Radiological Protection in NPPs in Korea NPP’s dosimetry system

Present state of nuclear power plants in Korea Kori unit 1 started commercial operation in 1978 The first Korea Standard Nuclear Power Plant(Ulchin unit 3, OPR-1000) completed the construction in1998 The first concrete casting for 1.4 million kW-level(APR-1400) Shin-Kori uint 3 in 2008 20 units in operation (16-PWR, 4-PHWR) 24 % of power facility & 36 % of electricity use

Optimal radiation protection NPP’s dose registry system Dose report to the MEST Dose control Dose statistics Optimal radiation protection ERP(RAM) System External Shallow, deep, neutron, extremity Management of radiation workers Issue of radiation work permit Radiation dose registry Internal Designation of radiation worker Control of RCA entrance / exit

NPP’s radiation exposure control Start Satisfaction of the dose limit, training, medical test, WBC or H-3 check Non-homogeneous Exposure Exposure exceeding 3 mSv, & 1.5 times of chest dose, & Dose rate exceeding 1mSv/hr Radiation Work Permit ? Exposure exceeding 4 mSv, & 2 times of whole body dose Yes No + Neutron γ, β emitters ? Yes Wearing the Neutron TLD & PD No No Homogeneous Exposure ? Whole body Extremity ? Wearing the extremity TLD Yes Yes Wearing the additional TLD & Alarm dosimeter (Chest & Back) 1

NPP’s radiation exposure control 1 Wearing the Chest TLD & Alarm dosimeter Airborne Radioactive Materials > 1 DAC Yes Wearing the mask No ERP(RAM) System RWP & Dose & Entrance requisite RCA Control system 2

NPP’s radiation exposure control 2 Radiation work ERP(RAM) System Alarm dosime- ter dose & Work record RCA Control system Yes Abnormal situation of alarm dosimeter ? TLD dose reading promptly No When alarm dosimeter is lost / destroyed or displayed over-range / higher dose 3

Biological or mathematical NPP’s radiation exposure control 3 Site inspection - Dose rate & energy measurement - Simulation of work situation - Fellow’s dose & interview Yes Abnormally exposed worker ? No No > Dose Limit ? Yes Professional institute (RHRI) Biological or mathematical dose reconstruction Worker who exceeded annual dose limit or lost / destroyed his personal dosimeter National dose evaluation committee Determination of the abnormally exposed worker’s dose 4

NPP’s radiation exposure control 4 Urine analysis for H-3 Working in the airborne radioactive materials or high contamination area When nose contamination is detected Yes LSC PHWR ? No WBC Yes Necessity of the internal dosimetry ? No TLD reading monthly RAM System Non-homogeneous Exposure HE = 0.55[HP(10)] (chest) + 0.50 [HP(10)] (Back) End

Current Status of Radiological Protection in NPPs in Korea KHNP - Radiation Health Research Institute Current Status of Radiological Protection in NPPs in Korea NPPs’ ALARA Program

Laws regarding ALARA Korea atomic energy law Enforcement Ordinance 1995 : Adoption of the “ALARA” concept Korea atomic energy law Release quantities of radioactive material to the environment and occupational radiation doses are maintained ALARA 1999 : Requirement to implement “ALARA”” Enforcement Ordinance 2000 : Requirement to implement “ALARA”” MEST notice

Equipment improvements for ALARA in existing NPP KHNP’s ALARA program Equipment improvements for ALARA in existing NPP KHNP has performed a substantial amount of equipment improvements in order to meet the dose limitations PSAR preliminary safety analysis report ALARA Design of Korea standard nuclear power plant KSNPs are being constructed with an enhanced design based on the experiences of the existing plants. Year of 2008, average individual dose  1.1 mSv/yr KSNP  0.5 mSv/yr

ALARA Procedure in operating NPP KHNP’s ALARA program ALARA Procedure in operating NPP Any Works Expected dose Under 10 man-mSv Expected Dose 10 ~ 70 man-mSv Expected Dose 70 ~ 200 man-mSv Expected Dose Over 200 man-mSv Use general RWP - Use RWP Evaluate expected dose Work group should make - Expected Dose sheet and ALARA check list ALARA Subcommittee( Committee) Review & approve Review after works and If actual dose exceeds 25% of expected dose Feedback ALARA subcommittee (Committee) Review, discuss & apply : dose reduction method to repeated works

Current Status of Radiological Protection in NPPs in Korea KHNP - Radiation Health Research Institute Current Status of Radiological Protection in NPPs in Korea Exposure trends of NPP workers

Dose distribution by operation state (1990 ~ 2007) Normal operation 23 % Refueling 77 %

Dose distribution by exposure type (1990 ~ 2007) Neutron dose 2.7 % Internal dose 5.3% PWR 0.01% Gamma 92.0 %

Annual individual dose trend of NPP workers

Radiation dose distribution of NPP workers ≥20 ≥15 ≥10 Year

Annual collective dose trend of NPP workers (man/unit)

WANO PI report

Current Status of Radiological Protection in NPPs in Korea KHNP - Radiation Health Research Institute Current Status of Radiological Protection in NPPs in Korea RHRI’s Activity for NPP’s RP

Radiation emergency medical preparedness for NPP WHO/REMPAN Liaison Institute 24hr Emergency Response Program Maintenance of REMP system with NPP appointed hospitals Education/ Training Program -Primary H. Secondary H. * REMP : Radiation Emergency Medical Preparedness

Radiation Dose Assessment Accidental dose evaluation system Decision-making for the treatment of patient caused by radiation exposure Biological Assessment Clinical Evaluation CA, FISH, MN, PCC Clinic symptoms Radiation Dose Assessment Physical Assessment Mathematical Assessment ESR, WBC, LSC Body Activation Analysis MCNP, VOXEL

Electron Spin Resonance System Tooth Ring Watch C.P. Sugar Ceramics Quartz Spectrum in teeth Dose response curve

Body Activation Analysis System Modified BOMAB : 製作 血液分析 Neutron spectrum : Excel 開發 照射 NPP AAS HPGe KBADA BSS Water Slab Phantom : 製作 Dose assessment S/W:Visual Basic 開發 線量評價 MCNP-X 模寫

Development of Korean Phantom

Technical support about Internal dosimetry for Study on internal dosimetry Fast Scan MCNP CRM 改善 Inter-Comparison Accu-Scan HPGe Technical support about Internal dosimetry for NPPs in Korea Korean Phantom 開發 Measurement system 構築 Guide Guideline Training of NPP members IDEAS Guideline Wound model Guide S/W 開發

Program for Estimating Probability of Causation Radiation dose reconstruction, PC calculation & epidemiologic investigation Program for Estimating Probability of Causation

Low dose radiation research

Application study of ICRP new recommendation 2011(?) (?)

Thank You ! Korea Hydro & Nuclear Power Co., LTD Radiation Health Research Institute