1

OCCUPATIONAL　 EXPOSURE　　　　at　 JAPANESE　NUCLEAR　POWER　 PLANTS　 in　 2005

OCCUPATIONAL　 EXPOSURE　　　　at　 JAPANESE　NUCLEAR　POWER　 PLANTS　 in　 2005

October 　 12, 2006

Shigeyuki 　 Wada

Safety Information Division

Japan Nuclear Energy Safety Organization 　 (JNES)

 2006　 Asian　 ISOE　 ALARA　Symposium

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1. General Status of NPPs in Japan

2. Analysis of Exposure in FY 2005

3. Improvement on Inspection Way

ContentsContents

3

Nuclear Power Plants in JapanNuclear Power Plants in Japan

BWR PWR Total

In Operation

No. of Units 32 23 55

Output (MWe) 30,214 19,366 49,580

Under Construction

No. of Units 1 1 2

Output (MWe) 1,373 912 2,285

On Planning

No. of Units 9 2 11

Output (MWe) 11,869 3,076 14,945

as of March 31, 2006

4

55 Units in Operation (PWR 23, BWR 32) as of March 31, 2006

女川福島第一

ふげん(2003年より廃止措置準備中)

(FBR))(

敦賀

志賀

出力規模

50万kW未満 100万kW未満 100万kW以上 合計 53基 出力47,122MWe

7 8

TEPCO　21

55

(FBR))(22

7 8

TEPCO　21

555

Oma

Tomari

Higashi　DoriOnagawa

Tokai　No.　2

Hamaoka

IkataSendai

Genkai

Shimane

Kaminoseki

Takahama

Oi

Mihama

Tsuruga

Tokai

Fugen(on　a　decommissioning　stage　since　2003)

Monju

Shika

Higashi　Dori

Fukushima　Daiichi

Fukushima　Daini

(On　the　decommissioning　stage　since　1998)

Namie　Kodaka

Kashiwazaki-　kariwa

３３

Output　scale

In　operationUnder　Construction

On　planning　stageLess　than　

1,000,000kW 1,000,000kW

Total 55 Units 49,580MWe

(PWR 23 units, BWR 32 units )500,000kW

Less　than More　than

Nuclear Power Plants in JapanNuclear Power Plants in Japan

5

Trend of Capacity Factor in Japanese plants

Trend of Capacity Factor in Japanese plants

6

Occupational　 Exposure　 in　 2005　Fiscal　 Year　 (April　 2005　–　March　

2006)

Occupational　 Exposure　 in　 2005　Fiscal　 Year　 (April　 2005　–　March　

2006)

Plants Units Person-Sv Person-Sv/Unit

BWR ３２ ４４．５１ １．３９

PWR ２３ ２２．３０ ０．９７

GCR １ ０．１０ ０．１０

Total ５６ ６６．９１ １．２１(LWR)

7

Individual　Dose　 in　 200５　 Fiscal　Year　 (April　 2005　–　March　 2006)Individual　Dose　 in　 200５　 Fiscal　Year　 (April　 2005　–　March　 2006)

Plants Units Persons mSv/Person

BWR ３２ ４４，２９７ １．０

PWR ２３ ２１，８００ １．０

GCR １ １，３５１ ０．１

Total ５６ ６６，３２２ １．０

8

Trend of BWR　 Exposure　 per　Unit　in　 Japanese plants

Trend of BWR　 Exposure　 per　Unit　in　 Japanese plants

00.5

11.5

22.5

3

89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05

Fiscal Ｙｅａｒ

Ｐｅｒ

ｓｏｎ

－Ｓ

ｖ

0

20

40

60

80

100

Ｅｘｐｏｓｕｒｅ ＣａｐａｃｉｔｙＦａｃｔｏｒ

9

Trend of PWR　 Exposure　 per　Unit　in　 Japanese plants

Trend of PWR　 Exposure　 per　Unit　in　 Japanese plants

0

0.5

1

1.5

2

89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05

Fiscal Ｙｅａｒ

Ｐｅｒ

ｓｏｎ

－Ｓ

ｖ

0

20

40

60

80

100

Ｅｘｐｏｓｕｒｅ ＣａｐａｃｉｔｙＦａｃｔｏｒ (%)

10

Trend of Maintenance Exposure 　at Japanese BWRs

Trend of Maintenance Exposure 　at Japanese BWRs

Plant NameOnagawa-1Onagawa-2Onagawa-3Fukushima No.1-1 1.33

Fukushima No.1-2Fukushima No.1-3 1.65

Fukushima No.1-4 1.94

Fukushima No.1-5 4.42

Fukushima No.1-6 0.8

Fukushima No.2-1Fukushima No.2-2Fukushima No.2-3Fukushima No.2-4 0.6

Kashiwazaki・K-1Kashiwazaki・K-2Kashiwazaki・K-3 0.67

Kashiwazaki・K-4 0.5 0.58

Kashiwazaki・K-5 0.64

Kashiwazaki・K-6Kashiwazaki・K-7Hamaoka-1Hamaoka-2Hamaoka-3Hamaoka-4 1.12

Hamaoka-5Shika-1Shika-2Shimane-1 0.98

Shimane-2 0.4 0.49

Tokai No.2Tsuruga-1

<1.5/ y1.5～3/ y3～4.5/ y4.5/ y

0.81

2.9

5.561.47

3.36

1.471.97

0.781.07

1.187.94

11.159.43

2005

0.62

4.43

4.4 7.195.63

3.714.96 2 1.91 2.4 1.2 3.6 2.4 2.8

5.9 2.3 7.51 3.79 1.5 4.94 2 12.72 1.66.4 3.33 2.84 3.8 1.6 2.6 6.34 1.6 5.9

5.014.63 2.86 4.81 3.84 4.97 16.9 5.4 8.715.86 3.83 3.7 6.26 1.89 2 15.54 1.1 2.81

1.6 8.57 2.7 10.88.52 5.38 3.03 3.48

0.7 0.6

0.2 0.3

200420001.07

0.2 0.3 0.4 0.5 0.95 1.420.81.1 0.6 0.5 1.21 0.6 1.45 1.4

20021995 1996 1997 19984.13

20031993 1994 200119991989 1990 1991 1992

1.8 4.82 1.1 2.47 1.3 1.9 0.8 2.05 0.6 1.4 1.79

0.76

3.04 1.1 2.29 0.9 1.1 0.9 1.4 0.6 1.7 1.1 2.9810.1 1.8 1.11 2.1 0.7 1.2 0.8 1.8 1.3 3.19

0.8 1.91 0.48 4.07

0.8 3.651.2

0.6 0.4 1.72 0.9 0.6 1.67 0.7 0.61 1.20.4 1.29 1 1 1.9 5.61

0.3 0.5 0.6 0.9 1.68 0.61.2 2.7

0.3 0.8 1.7 0.95 1.7 3.570.1 0.3 0.5 2 1.75

0.2 0.6 0.9 1 0.9 2.16 0.7 1.2 2.990.3 0.3 0.3 1.2 0.8

0.2 0.3 0.4 1.3 0.649.6 5.26 2.4 14 1.8 2.7 2.4 2.98

3.85 2.2 3.89 2.53.84 4.16 2 2.3 1.5 1.932.59

1.1 2 1.99.23

0.8 0.7 0.73 1.48 4.98 5.080.5 0.9 0.8 2.4 0.7 4.31

0.7 1.81.55

0.2 0.6 0.9 1.6 1.8 0.9 1.1 3.03 1.1

1.58 1.1 1.3 2.95 4.85 4.1 1.1 9.920.6 0.5 0.7 0.30.2 0.3 0.4 0.5 1.4 1.5

0.9 2.43

5.1 3.4 3.72 2.3 2.5 2.1 3.7 5.94 2.98 2.21 32.6 2.9 3.67 2.92 2.4 2.2 3.51 7.33 1.1 1.4 1.3

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Trend of Maintenance Exposure 　at Japanese PWRs

Trend of Maintenance Exposure 　at Japanese PWRs

nameTomari-1 0.6

Tomari-2Mihama-1 0.98

Mihama-2 0.41

Mihama-3 1.31

Takamaha-1Takamaha-2 5.21 1.18 1.29 0.84

Takamaha-3Takamaha-4 0.79 1.52

Ohi-1Ohi-2Ohi-3 0.74 1.66 0.99

Ohi-4Ikata-1Ikata-2Ikata-3 0.71

Genkai-1Genkai-2Genkai-3Genkai-4 1.12

Sendai-1 1.2

Sendai-2 1.14

Truruga-2

<1/ y1 2～ / y2 3～ / y3/ y

0.85

0.71

1.39

1.41

2.191.68

2.281.1

0.55

1.38

1.13

20050.45

0.50.78

1.12 1.12 1.22 1.961.76

1.33 1.59 2.08

0.73 1.09 1.84 0.84 0.91 1.22 0.89

1.14 1 0.95 1.151.27 1.1 1.41 1.23

0.61 0.58 1.31 1.29

1.2 0.86

0.45 0.56 0.42 0.61 1.05 1.22 1.66

1.69

0.43

1.67 2.091.09 1.6 1.76

0.45

1.22 1.05 1.41 1.55

1.37 1.56 0.8 0.87

0.68 1.32.6 3 2.08 1.61 0.93 1.16 1.32 1.39

0.43 0.3 0.3 0.53

0.51 0.590.4 0.38 0.52 0.570.43 0.39 0.45 0.46

2003 20040.61 0.59 0.46 0.54 0.53 0.74 0.83

2000 20011999 20021995 1996 1997 19981993 19940.4 0.39 0.54 0.51

1989 1990 1991 1992

1.71 1.61 2.01 1.443.72 2.43 1.48 2.81 2.43

1.82 5.9 1.88 1.7 1.39 1.02 2.59 0.54

5.130.75

2.82 1.65 2.56 2.07 2.58 2.54 1.08 1.31 1.33 0.71

3.18 2.51 3.07 2.74 3.03 2.91 1.08 1.86 1.09 1.28 1.43 0.97

4.46 2.19 2.74 2.46 1.89 1.28 1.16 0.851.19

1.33 0.7 0.66 0.74 1.13 1.23 1.07 0.81 1.29 2.35 1.22 1.951.53 0.47 0.64 0.6 0.87 1.2 1.43 1.03 1.05 1.7

6.73 8.27 6.03 7.62 5.12 3.4 3.52 3.78 2.41 1.95 1.75 1.724.37 2.64 4.55 3.97 2.89 4.94 4.42 1.92 1.6 1.5 1.72

0.52 0.55 0.61 0.62 0.7 0.59 0.88 2.920.5 0.59 0.53 0.46 0.57 0.7 0.58 0.82 0.56

1.31 1.43 0.92 1.01 0.76 0.71 1 1.48

1.29

1.2 2.2 1.69

2.660.71 1.15 1.26 0.920.77 1.19 0.94 1.17 1.62 1.11

1.381

0.8 1.56 0.77 0.71 0.79 0.68 0.94 0.84 3.580.68 1.68 0.86 1.29

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BWR Average Exposure per Unit　 by Country

BWR Average Exposure per Unit　 by Country

00.5

11.5

22.5

33.5

94 95 96 97 98 99 00 01 02 03 04 05

Year

Per

son-

Sv/R

eact

or J APANUSAGERMANYSWEDENFINLANDSWITZERLAND

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PWR Average Exposure per Unit　 by Country

PWR Average Exposure per Unit　 by Country

0

0.5

1

1.5

2

2.5

94 95 96 97 98 99 00 01 02 03 04 05

Year

Per

son-

Sv/R

eact

or J APANUSAGEAMANYFRANCEBELGIUMKOREA

14

Duan

e Arn

old

Limer

ick1,2

Hatc

h 1,2

Pilgri

m

Grand G

ulf

Susq

ueha

nna 1

,2

Verm

ont Y

anke

e

Peac

h Bott

om2,3

Oyster

Cree

k

Dres

den 2

,3

LaSa

lle 1,

2

Perry

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

USA

J apan

Per

son-

Sv/

Rea

ctor

Ona

gawa

Kas

hiwaz

akik

arih

aHam

aoka

Fuku

shim

adai

ini

Shi

man e

Shi

ka

From 2002 to 2004

From 2003 to 2005

MIN:0.59MAX:4.56

MIN:0.64MAX:3.29

Tsu

ruga

BWR　 Three　 Year　 Rolling　 Average　by　 Plant　 in　USA　 and　 Japan

BWR　 Three　 Year　 Rolling　 Average　by　 Plant　 in　USA　 and　 Japan

Fuku

shim

amai

ich

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PWR　 Three　 Year　 Rolling　 Average　by　 Plant　 in　USA　 and　 Japan

PWR　 Three　 Year　 Rolling　 Average　by　 Plant　 in　USA　 and　 Japan

I nd i a n Pt . 3

C ry st al R i v er 3

S ea br oo k

G i n na

P ra i r i e I sl an d 1, 2

P al V er de 1 , 2 , 3

P t . B ea ch 1 , 2

V og t l e 1, 2

C at awba 1 , 2

B ra i d wo od 1 , 2

McGui r e 1 , 2

S t . L uc i e

R ob i n so n 2

B ea ve r Va l l ey 1 , 2

S ur r y 1 , 2

Oco ne e 1, 2, 3

S ou t h T ex as 1 , 2

C oo k 1, 2

S an Ono f r e 2, 3

F t . C al ho un

P al i s ad es

0

0.5

1

1.5

2

2.5

USAJ apanFrom 2002 to 2004

Per

son-

Sv/

Rea

ctor

Tom

ar

Tak

aham

Mih

am

Ikat

a

Gen

kai

Sen

daTru

ruga

Ohi MIN:0.63

MAX:1.76

MIN:0.36MAX:2.1

From 2003 to 2005

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　５ -year Dose Reduction Goals　 in　USA　５ -year Dose Reduction Goals　 in　USA

2005 2010

Exposure (BWR) 1.20 person-Sv(1.65)

1.20 person-Sv

Exposure (PWR) 0.65 person-Sv(0.76)

0.60 person-Sv

Capability Factor 91 92

Forced Loss Rate 2.0 1.0

Automatic Scram <1.0 <0.5Safety System % Unavailability 2 or 2.5 2 or 2.5

Fuel Defects 0 0

Chemical Index 1.10 1.01Industrial Safety Accident Rate 0.30 0.20

( )2005 Quarter 3 Performance

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Dose Rate at PLR Piping in both Japanese BWR and US BWR

Dose Rate at PLR Piping in both Japanese BWR and US BWR

0

0.5

1

1.5

2

1 2 3 4 5 6 7 8 9

Outage Number

mSv

/h

US Plant(Fermi- 2) J apan(Hamaoka- 3)

18

<0.5

0.5-

1.0

1.0-

1.5

1.5-

2.0

2.0-

2.5

2.5-

3.0

3.0-

3.5

3.5-

4.0

>4.0 J apan

02468

1012

J apanUSA

Dose Rate at PLR Piping in both Japanese BWR and US BWR

Dose Rate at PLR Piping in both Japanese BWR and US BWR

mSv/h at PLR Piping

Num

ber

Median:1.55 mSv/h

Median:0.89 mSv/h

Japan:2000.12-2003

USA :2005.1

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Operation Period and Maintenance Period by Country　 from　 1994　 to　 2004

Operation Period and Maintenance Period by Country　 from　 1994　 to　 2004

Operation 　 Period 　(days) 　

◆USA

■Finland

▲Korea

×Japan

жSwitzerland

●Belgium

Mai

nten

ance

　P

erio

d　

(day

s)　

Capacity Factor 90% 　

Capacity Factor

80% 　

0

20

40

60

80

100

120

140

0 100 200 300 400 500 600 700

Operating period days（ ）

Out

age

days

（）

USA

Finland

Korea

J apan

Switzerland

Belgium

Capacity Factor ９０％

Capacity Factor ８０％

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Mandatory 　 Inspection Items in Japanese 　 BWRsMandatory 　 Inspection Items in Japanese 　 BWRs

System Disassembled Inspection ISI No Equipment 　 or 　 Components

　 ○ 1 Category One 　 & 　 Three Mechanism

　 Reactor ○ 　 2 Main Steam Safety Valve

　 Cooling ○ 　 3 Main Steam Relief Safety Valve

System ○ 　 4 High Pressure Injection System Pumps & Valves

　 ○ 　 5 Residual Heat Removal （ RHR) 　 Pumps 　 & 　 Vaves 　

　 ○ 　 6 Core Spray Pumps 　 & 　 Valves

　 ○ 　 7 Low Pressure Core Spray Pumps 　 & 　 Valves

　 ○ 　 8 High Pressure Core Spray Pumps 　 & 　 Valves

Instrument & ○ 　 1 CRD Mechanism Control System ○ 　 2 Scram Valves of Hydraulic Control Unit

Pressure ○ 　 1 PCV Isolation Valves

Containment ○ 　 2 PCV Spray Pumps 　 & 　 ValvesVessel (PCV) ○ 　 3 Flammability Control System 　 ValvesDiesel Power ○ 　 1 Emergency 　 Diesel 　 Power 　Generator Generator ○ 　 2 High Pressure Core Spray DG

Turbine ○ 　 1 Turbine *

*　 Shall be inspected within 13months after former inspection

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Mandatory 　 Inspection Items in Japanese 　 PWRsMandatory 　 Inspection Items in Japanese 　 PWRs

System Disassembled Inspection ISI No Equipments or Components

　 ○ 1 Category One 　 & 　 Three Mechanism

　 Reactor 　 ○ 2 Category Three Piping in Reactor Containment Vessel

Cooling ○ 　 3 Pressurize Safety Valves

　 System ○ 　 4 Pressurize Relief Valves

　 ○ 　 5 High Pressure Injection System Pumps & Valves

　 ○ 　 6 Low Pressure Injection System Pumps & Valves

　 ○ 　 7Accumulator Injection System Valves 　

　 ○ 　 8 Component Cooling System Pumps

　 ○ 　 9 Main Steam Safety Valves

　 ○ 　 10 Main Steam Relief Valves

　 ○ 　 11 Main Steam Isolation Valves

Instrument & ○ 　 1 Boric Acid PumpsControl System ○ 　 　 　

○ 　 1 PCV Isolation Valves

PCV ○ 　 2 PCV Spray Pumps 　 & 　 ValvesDiesel Power Generator

○ 　 1 Emergency 　 Diesel 　 Power 　 Generator

Turbine ○ 　 1 Turbine

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Improvement on Inspection Way Improvement on Inspection Way

NISA submitted the draft report “ Improvement on Inspection Way for Nuclear Facilities ” September 2006.

(Utilities) Maintenance program ・ Condition-directive maintenance・ Time-based maintenance ・Online maintenance

NISA

Approval

(Applied in 2008)

23

SummarySummary

• Japanese plants had 1.21 person-Sv/unit in 2005 which is lower than 2004 by 0.23 person-Sv. However it is still the highest level in the world.

• Japanese plants do not have much source term and perform relatively more maintenance work which may increase the exposure.

• NISA submitted the draft report for the improvement on inspection way including maintenance program with condition-directive maintenance and online maintenance etc.

• It is expected that the maintenance improvement will promote to decrease the exposure in Japanese plants.

24

Thank you for your attention !!

25

Source Term Reduction Measures in 　 Japanese BWRs

Source Term Reduction Measures in 　 Japanese BWRs

Measures Applied　plants

CrudReduction

O2Injection All Plants

Condensate Filters 29/31

Improved Material (Weatherability Steel) for Condensate System

21/31

Improved Material (Low Alloy Steel) for Feed Water Heater Shells 　　

All　 Plants

CoReduction

Improved Material（ Low Cobalt )for Reactor Core Structures　

All Plants

Improved Material (Low Cobalt) for Feed　Water Heating System　　

25/31

26

Source Term Reduction Measures in 　 Japanese PWRsSource Term Reduction Measures in 　 Japanese PWRs

Measures Applied　plants

CrudReduction

pH Control All Plants

Oxidation Operation in Shutdown Stage All　 Plants

Clean-up Feed Water Operation in　Shutdown Stage

All　 Plants

CoReduction

Improved Material（ Low Cobalt ) for Reactor Core Structures　

18/23

Improved Material (Low Cobalt) of Steam Generators　

21/23