PRA

100620

PRAProbabilistic Risk Assessment (QRA)19601975WASH-14001988 IPE + IPEEE1995NRCPRA policy statement()PRAPRA

From Feb. 2009 NEI(T. Pietrangelo to USNRC)

NRC(Safety Goal) (Quantitative Health Objective, QHO)(1986)(1 mile)0.1% 110-5 /yr (QHO)

EPZNUREG-0396 (MACCS2) * (NUREG-0396)100110-4NUREG-039670% (170%) 110-4 = 310-5 100

*NUREG-0396 (EPA 520/1-78-016), "Planning Basis for the Development of State and Local Government Radiological Emergency Response Plans in Support of Light-Water Nuclear Power Plants," USNRC, December 1978. H.N. Jow, J.L. Sprung, J.A. Rollstin, L.T. Ritchie, and D.I. Chanin, MELCOR Accident Consequence Code System (MACCS). NUREG/CR-4691, Sandia National Laboratories, Albuquerque, USA (1990).From: 100.5.31

()RG 1.174

PRiSESDP2006PRiSE

PRA/()How likely is it?What are the consequences?What can go wrong?//

(0.5g PGA) + (, 10~14)AC (loss of almost all I&Cs) (SBO)

IAEA(2002) 14/11/80 Garigliano 3/12/82 Dresden 6031/3/94 Cooper ()13/12/80 Hinkley 22/1/84 Borssele ()() 12/1999 Blayais 1985 17 (source: NRC generic reports in IRS)11/7/2000 Chernobyl 3 RF

IAEA(2002)(1) ()17/10/80 Indian Point 87+11/12/89 Clinton 12/1/87 St. Laurent 19801990 ()1985 (33)(UHS)1982 1999 800

IAEA(2002)(2)30 19885 32 134 6 () 6 2 3

IAEA(2002)

1CooperBWR19937RCIC

2Calvert CliffsPWR20024158260/

3Davis-Besse19986F2113156 mph99%11ECCS41NRC24110140

4Turkey Point1992830145mph175mph564CST

(SBO)copingACSBO SBOACACSBO

SBOAC44coping SBO4coping4ACAC60

SBO()AC(MOV)RCICHPCI()357(Class 1)125

Sheet1

ABCDFCCDP

E(K)R(V)R(P)E(W)A(P)C(M)O(P)D(0)D(5)S(A)

S01OK6.7E-020.0E+00

S02ES7.9E-052.6E-073.3E-03

S03EO7.0E-054.8E-076.9E-03

S04EOS8.2E-068.7E-081.1E-02

S05EO52.8E-063.9E-081.4E-02

S06EO5S8.4E-072.5E-083.0E-02

S07EOD1.5E-11

S08EODS7.3E-117.3E-111.0E+00

S09CM2.0E-102.0E-101.0E+00

S10EC1.9E-061.5E-077.8E-02

S11ECS3.6E-071.4E-084.0E-02

S12ECO8.6E-071.3E-071.5E-01

S13ECOS5.0E-075.3E-081.1E-01

S14CM9.3E-119.3E-111.0E+00

S15CM3.2E-063.2E-061.0E+00

S16CM2.7E-092.7E-091.0E+00

S17CM7.5E-087.5E-081.0E+00

S18CM1.0E-061.0E-061.0E+00

6.7E-02

1.7E-041.0E-06WinNUPRA

5.6E-06CDF

0.00251

()

SBO

SBO

11()////

11()5480V /

11(1)

ECW

11(2)

/

11(3)()()//

(Gas turbine)

To Power Grid

To Power Grid

Breaker

Breaker

Breaker

Breaker

Breaker

Breaker

NO

NO

161 KV BUS 2

NC

NC

NO

NO

NO

To Unit 1 RAT 2

To Unit 1 RAT 1

161 KV BUS 1

To Unit 2 RAT 1

To Unit 2 RAT 2

BREAKER

VVVVVV

VVVV

TRANSFORMER

GAS TURBINE

GT

NO

NC

NC

NO

NO

NC

NC

0.61g and U=0.18, R=0.08

PRA

67% (CDF)98% (LERF)

()1 Case 2 1.2

Region III

Region II

Region I

1E-5

1E-7

1E-5

1E-4

CDF(/RY)

1E-6

1E-5

LERF(/RY)

1E-6

1E-6

DCDF(/RY)

DLERF(/RY)

CDF

LERF

CDF

LERF

Case 2

Case 1

1CDF 9.5%LERF2.3% 1 220%CDF5.6E-7/ (-9.2%)LERF 5.5E-8/ (-7.5%)

125DC24()()RHR AB()()()

PRA()PRA(PRA)

A. Giddens (UK)() 911D. Ropeik (USA, 2011)Michigan9111,018

PRAPRAPRA()PRAPRAPRAIAEAPRA