Risk-Based Structural Integrity Management of Offshore...

Risk-BasedStructural Integrity Management of

Offshore Jacket Structures

Guidance Note April 2017 NI 624 DT R00 E

Risk-Based Structural Integrity Management of

Offshore Jacket Structures

April 2017

Guidance Note NI 624 DT R00 E

Marine & Offshore 92571 Neuilly sur Seine Cedex – France

Tel: + 33 (0)1 55 24 70 00 – Fax: + 33 (0)1 55 24 70 25 Website: http://www.veristar.com

Email: [email protected] 2017 Bureau Veritas - All rights reserved

Bur

eau

Verit

as

Mar

ine

& O

ffsho

re

Gen

eral

Con

ditio

nsca

refu

lly fo

llow

ed a

t all

times

by

the

Clie

nt.

2.12

“Se

rvic

es”

mea

ns th

e se

rvic

es s

et o

ut in

cla

uses

2.2

and

2.3

bu

t al

so o

ther

ser

vice

s re

late

d to

Cla

ssifi

catio

n an

d C

ertif

icat

ion

such

as,

but

not

lim

ited

to: s

hip

and

com

pany

saf

ety

man

agem

ent

certi

ficat

ion,

shi

p an

d po

rt se

curit

y ce

rtific

atio

n, tr

aini

ng a

ctiv

ities

, all

activ

ities

and

dut

ies

inci

dent

al t

here

to s

uch

as d

ocum

enta

tion

on

any

supp

ortin

g m

eans

, so

ftwar

e, i

nstru

men

tatio

n, m

easu

rem

ents

, te

sts

and

trial

s on

boa

rd.

2.13

“So

ciet

y” m

eans

the

cla

ssifi

catio

n so

ciet

y ‘B

urea

u Ve

ritas

M

arin

e &

Offs

hore

SA

S’, a

com

pany

org

aniz

ed a

nd e

xist

ing

unde

r th

e la

ws

of F

ranc

e, r

egis

tere

d in

Nan

terre

und

er t

he n

umbe

r 82

1 13

1 84

4,

or a

ny o

ther

lega

l ent

ity o

f Bur

eau

Verit

as G

roup

as

may

be

spec

ified

in th

e re

leva

nt c

ontra

ct, a

nd w

hose

mai

n ac

tiviti

es

are

Cla

ssifi

catio

n an

d C

ertif

icat

ion

of s

hips

or o

ffsho

re u

nits

. 2.

14 “

Uni

t” m

eans

any

shi

p or

ves

sel o

r of

fsho

re u

nit o

r st

ruct

ure

of a

ny ty

pe o

r par

t of i

t or s

yste

m w

heth

er li

nked

to s

hore

, riv

er b

ed

or s

ea b

ed o

r no

t, w

heth

er o

pera

ted

or lo

cate

d at

sea

or

in in

land

w

ater

s or

par

tly o

n la

nd, i

nclu

ding

sub

mar

ines

, hov

ercr

afts

, dril

ling

rigs,

offs

hore

ins

talla

tions

of

any

type

and

of

any

purp

ose,

the

ir re

late

d an

d an

cilla

ry e

quip

men

t, su

bsea

or

not,

such

as

wel

l hea

d an

d pi

pelin

es,

moo

ring

legs

and

moo

ring

poin

ts o

r ot

herw

ise

as

deci

ded

by th

e So

ciet

y.

3. S

CO

PE A

ND

PER

FOR

MA

NC

E 3.

1 Th

e So

ciet

y sh

all p

erfo

rm t

he S

ervi

ces

acco

rdin

g to

the

app

li-ca

ble

natio

nal

and

inte

rnat

iona

l st

anda

rds

and

Indu

stry

Pra

ctic

e an

d al

way

s on

the

ass

umpt

ion

that

the

Clie

nt i

s aw

are

of s

uch

stan

dard

s an

d In

dust

ry P

ract

ice.

3.

2 Su

bjec

t to

the

Serv

ices

per

form

ance

and

alw

ays

by re

fere

nce

to

the

Rul

es, t

he S

ocie

ty s

hall:

•

revi

ew t

he c

onst

ruct

ion

arra

ngem

ents

of

the

Uni

t as

sho

wn

on

the

docu

men

ts p

rovi

ded

by th

e C

lient

; •

cond

uct t

he U

nit s

urve

ys a

t the

pla

ce o

f the

Uni

t con

stru

ctio

n;

• cl

ass

the

Uni

t and

ent

ers

the

Uni

t’s c

lass

in th

e So

ciet

y’s

Reg

is-

ter;

• su

rvey

the

Uni

t pe

riodi

cally

in

serv

ice

to n

ote

that

the

req

uire

-m

ents

for

the

mai

nten

ance

of

clas

s ar

e m

et.

The

Clie

nt s

hall

info

rm th

e So

ciet

y w

ithou

t del

ay o

f any

circ

umst

ance

s w

hich

may

ca

use

any

chan

ges

on th

e co

nduc

ted

surv

eys

or S

ervi

ces.

Th

e So

ciet

y w

ill n

ot:

• de

clar

e th

e ac

cept

ance

or

com

mis

sion

ing

of a

Uni

t, no

r its

co

nstru

ctio

n in

con

form

ity w

ith it

s de

sign

, suc

h ac

tiviti

es r

emai

n-in

g un

der

the

excl

usiv

e re

spon

sibi

lity

of t

he U

nit’s

ow

ner

or

build

er;

• en

gage

in a

ny w

ork

rela

ting

to th

e de

sign

, con

stru

ctio

n, p

rodu

c-tio

n or

rep

air

chec

ks,

neith

er in

the

ope

ratio

n of

the

Uni

t or

the

Uni

t’s tr

ade,

nei

ther

in a

ny a

dvis

ory

serv

ices

, and

can

not b

e he

ld

liabl

e on

thos

e ac

coun

ts.

4. R

ESER

VATI

ON

CLA

USE

4.

1 Th

e C

lient

sha

ll al

way

s: (

i) m

aint

ain

the

Uni

t in

good

con

ditio

n af

ter s

urve

ys; (

ii) p

rese

nt th

e U

nit a

fter s

urve

ys; (

iii) p

rese

nt th

e U

nit

for

surv

eys;

and

(iv

) in

form

the

Soc

iety

in

due

cour

se o

f an

y ci

rcum

stan

ces

that

may

affe

ct th

e gi

ven

appr

aise

men

t of t

he U

nit o

r ca

use

to m

odify

the

scop

e of

the

Serv

ices

.4.

2 C

ertif

icat

es r

efer

ring

to t

he S

ocie

ty’s

Rul

es a

re o

nly

valid

if

issu

ed b

y th

e So

ciet

y.4.

3 Th

e So

ciet

y ha

s en

tire

cont

rol o

ver

the

Cer

tific

ates

issu

ed a

nd

may

at

any

time

with

draw

a C

ertif

icat

e at

its

ent

ire d

iscr

etio

n in

clud

ing,

but

not

lim

ited

to,

in t

he f

ollo

win

g si

tuat

ions

: w

here

the

C

lient

fails

to c

ompl

y in

due

tim

e w

ith in

stru

ctio

ns o

f the

Soc

iety

or

whe

re th

e C

lient

fails

to p

ay in

acc

orda

nce

with

cla

use

6.2

here

un-

der.

5. A

CC

ESS

AN

D S

AFE

TY

5.1

The

Clie

nt s

hall

give

to

the

Soci

ety

all a

cces

s an

d in

form

atio

n ne

cess

ary

for

the

effic

ient

per

form

ance

of

the

requ

este

d Se

rvic

es.

The

Clie

nt s

hall

be t

he s

ole

resp

onsi

ble

for

the

cond

ition

s of

pr

esen

tatio

n of

the

Uni

t for

test

s, tr

ials

and

sur

veys

and

the

cond

i-tio

ns u

nder

whi

ch te

sts

and

trial

s ar

e ca

rried

out

. Any

info

rmat

ion,

dr

awin

gs, e

tc. r

equi

red

for t

he p

erfo

rman

ce o

f the

Ser

vice

s m

ust b

e m

ade

avai

labl

e in

due

tim

e.

5.2

The

Clie

nt s

hall

notif

y th

e So

ciet

y of

any

rel

evan

t sa

fety

issu

e an

d sh

all

take

all

nece

ssar

y sa

fety

-rel

ated

mea

sure

s to

ens

ure

a sa

fe w

ork

envi

ronm

ent f

or th

e So

ciet

y or

any

of i

ts o

ffice

rs, e

mpl

oy-

ees,

ser

vant

s, a

gent

s or

sub

cont

ract

ors

and

shal

l co

mpl

y w

ith a

ll ap

plic

able

saf

ety

regu

latio

ns.

6. P

AYM

ENT

OF

INVO

ICES

6.

1 Th

e pr

ovis

ion

of th

e Se

rvic

es b

y th

e So

ciet

y, w

heth

er c

ompl

ete

or n

ot,

invo

lve,

for

the

par

t ca

rried

out

, th

e pa

ymen

t of

fee

s th

irty

(30)

day

s up

on is

suan

ce o

f the

invo

ice.

6.2

With

out

prej

udic

e to

any

oth

er r

ight

s he

reun

der,

in c

ase

of

Clie

nt’s

pay

men

t def

ault,

the

Soci

ety

shal

l be

entit

led

to c

harg

e, in

ad

ditio

n to

the

amou

nt n

ot p

rope

rly p

aid,

in

tere

sts

equa

l to

twel

ve

(12)

mon

ths

LIBO

R p

lus

two

(2)

per

cent

as

of d

ue d

ate

calc

ulat

ed

on t

he n

umbe

r of

day

s su

ch p

aym

ent

is d

elin

quen

t. Th

e So

ciet

y sh

all

also

hav

e th

e rig

ht t

o w

ithho

ld c

ertif

icat

es a

nd o

ther

doc

u-m

ents

and

/or t

o su

spen

d or

revo

ke th

e va

lidity

of c

ertif

icat

es.

6.3

In c

ase

of d

ispu

te o

n th

e in

voic

e am

ount

, the

und

ispu

ted

porti

on

of th

e in

voic

e sh

all b

e pa

id a

nd a

n ex

plan

atio

n on

the

disp

ute

shal

l ac

com

pany

pay

men

t so

tha

t ac

tion

can

be t

aken

to

solv

e th

e di

sput

e.

7. L

IAB

ILIT

Y 7.

1 Th

e So

ciet

y be

ars

no l

iabi

lity

for

cons

eque

ntia

l lo

ss.

For

the

purp

ose

of t

his

clau

se c

onse

quen

tial

loss

sha

ll in

clud

e, w

ithou

t lim

itatio

n:

• In

dire

ct o

r con

sequ

entia

l los

s;

• An

y lo

ss a

nd/o

r de

ferr

al o

f pr

oduc

tion,

los

s of

pro

duct

, lo

ss o

f us

e, lo

ss o

f bar

gain

, los

s of

rev

enue

, los

s of

pro

fit o

r ant

icip

ated

pr

ofit,

loss

of

busi

ness

and

bus

ines

s in

terr

uptio

n, in

eac

h ca

se

whe

ther

dire

ct o

r ind

irect

. Th

e C

lient

sha

ll sa

ve,

inde

mni

fy,

defe

nd a

nd h

old

harm

less

the

So

ciet

y fro

m t

he C

lient

’s o

wn

cons

eque

ntia

l lo

ss r

egar

dles

s of

ca

use.

7.

2 In

any

cas

e, th

e So

ciet

y’s

max

imum

liab

ility

tow

ards

the

Clie

nt

is li

mite

d to

one

hun

dred

and

fifty

per

-cen

ts (1

50%

) of t

he p

rice

paid

by

the

Clie

nt t

o th

e So

ciet

y fo

r th

e pe

rform

ance

of

the

Serv

ices

. Th

is li

mit

appl

ies

rega

rdle

ss o

f fau

lt by

the

Soci

ety,

incl

udin

g br

each

of

con

tract

, bre

ach

of w

arra

nty,

tort,

stri

ct li

abili

ty, b

reac

h of

sta

tute

. 7.

3 Al

l cl

aim

s sh

all

be p

rese

nted

to

the

Soci

ety

in w

ritin

g w

ithin

th

ree

(3)

mon

ths

of th

e Se

rvic

es’ p

erfo

rman

ce o

r (if

late

r) th

e da

te

whe

n th

e ev

ents

whi

ch a

re r

elie

d on

wer

e fir

st d

isco

vere

d by

the

C

lient

. An

y cl

aim

not

so

pres

ente

d as

def

ined

abo

ve s

hall

be

deem

ed w

aive

d an

d ab

solu

tely

tim

e ba

rred

.

8. IN

DEM

NIT

Y C

LAU

SE

8.1

The

Clie

nt a

gree

s to

rel

ease

, ind

emni

fy a

nd h

old

harm

less

the

Soci

ety

from

and

aga

inst

any

and

all

clai

ms,

dem

ands

, law

suits

or

actio

ns f

or d

amag

es,

incl

udin

g le

gal

fees

, fo

r ha

rm o

r lo

ss t

o pe

rson

s an

d/or

pro

perty

tang

ible

, int

angi

ble

or o

ther

wis

e w

hich

may

be

bro

ught

aga

inst

the

Soc

iety

, in

cide

ntal

to,

aris

ing

out

of o

r in

co

nnec

tion

with

the

per

form

ance

of

the

Serv

ices

exc

ept

for

thos

e cl

aim

s ca

used

sol

ely

and

com

plet

ely

by t

he n

eglig

ence

of

the

Soci

ety,

its

offic

ers,

em

ploy

ees,

ser

vant

s, a

gent

s or

sub

cont

ract

ors.

9. T

ERM

INA

TIO

N

9.1

The

Parti

es s

hall

have

the

right

to te

rmin

ate

the

Serv

ices

(an

d th

e re

leva

nt c

ontra

ct)

for

conv

enie

nce

afte

r gi

ving

the

oth

er P

arty

th

irty

(30)

day

s’ w

ritte

n no

tice,

and

with

out

prej

udic

e to

cla

use

6 ab

ove.

9.2

In s

uch

a ca

se, t

he c

lass

gra

nted

to th

e co

ncer

ned

Uni

t and

the

prev

ious

ly i

ssue

d ce

rtific

ates

sha

ll re

mai

n va

lid u

ntil

the

date

of

effe

ct o

f th

e te

rmin

atio

n no

tice

issu

ed,

subj

ect

to c

ompl

ianc

e w

ith

clau

se 4

.1 a

nd 6

abo

ve.

10. F

OR

CE

MA

JEU

RE

10.1

Nei

ther

Par

ty s

hall

be r

espo

nsib

le f

or a

ny f

ailu

re t

o fu

lfil a

ny

term

or p

rovi

sion

of t

he C

ondi

tions

if a

nd to

the

exte

nt th

at fu

lfilm

ent

has

been

del

ayed

or

tem

pora

rily

prev

ente

d by

a f

orce

maj

eure

oc

curr

ence

with

out t

he fa

ult o

r neg

ligen

ce o

f the

Par

ty a

ffect

ed a

nd

whi

ch,

by t

he e

xerc

ise

of r

easo

nabl

e di

ligen

ce,

the

said

Par

ty i

s un

able

to p

rovi

de a

gain

st.

10.2

For

the

purp

ose

of th

is c

laus

e, fo

rce

maj

eure

sha

ll m

ean

any

circ

umst

ance

not

bei

ng w

ithin

a P

arty

’s r

easo

nabl

e co

ntro

l inc

lud-

ing,

but

not

lim

ited

to: a

cts

of G

od, n

atur

al d

isas

ters

, epi

dem

ics

or

pand

emic

s, w

ars,

ter

roris

t at

tack

s, r

iots

, sa

bota

ges,

impo

sitio

ns o

f sa

nctio

ns,

emba

rgoe

s, n

ucle

ar,

chem

ical

or

biol

ogic

al c

onta

min

a-tio

ns,

law

s or

act

ion

take

n by

a g

over

nmen

t or

pub

lic a

utho

rity,

qu

otas

or

proh

ibiti

on,

expr

opria

tions

, de

stru

ctio

ns o

f th

e w

orks

ite,

expl

osio

ns, f

ires,

acc

iden

ts, a

ny la

bour

or

trade

dis

pute

s, s

trike

s or

lo

ckou

ts

11. C

ON

FID

ENTI

ALI

TY

11.1

The

doc

umen

ts a

nd d

ata

prov

ided

to o

r pr

epar

ed b

y th

e So

ciet

y in

pe

rform

ing

the

Serv

ices

, and

the

info

rmat

ion

mad

e av

aila

ble

to t

he S

ocie

ty,

are

treat

ed a

s co

nfid

entia

l ex

cept

whe

re t

he

info

rmat

ion:

• is

alre

ady

know

n by

the

rec

eivi

ng P

arty

fro

m a

noth

er s

ourc

e an

d is

pr

oper

ly a

nd la

wfu

lly in

the

poss

essi

on o

f the

rec

eivi

ng P

arty

prio

r to

th

e da

te th

at it

is d

iscl

osed

;•

is a

lread

y in

pos

sess

ion

of t

he p

ublic

or

has

ente

red

the

publ

ic

dom

ain,

oth

erw

ise

than

thro

ugh

a br

each

of t

his

oblig

atio

n;•

is a

cqui

red

inde

pend

ently

fro

m a

thi

rd p

arty

tha

t ha

s th

e rig

ht t

o di

ssem

inat

e su

ch in

form

atio

n;•

is re

quire

d to

be

disc

lose

d un

der a

pplic

able

law

or

by a

gov

ernm

enta

l or

der,

decr

ee,

regu

latio

n or

rul

e or

by

a st

ock

exch

ange

aut

horit

y (p

rovi

ded

that

the

rece

ivin

g Pa

rty s

hall

mak

e al

l rea

sona

ble

effo

rts to

gi

ve p

rom

pt w

ritte

n no

tice

to th

e di

sclo

sing

Par

ty p

rior

to s

uch

disc

lo-

sure

.11

.2 T

he S

ocie

ty a

nd t

he C

lient

sha

ll us

e th

e co

nfid

entia

l in

form

atio

n ex

clus

ivel

y w

ithin

the

fram

ewor

k of

thei

r ac

tivity

und

erly

ing

thes

e C

ondi

-tio

ns.

11.3

Con

fiden

tial i

nfor

mat

ion

shal

l onl

y be

pro

vide

d to

third

par

ties

with

th

e pr

ior

writ

ten

cons

ent o

f the

oth

er P

arty

. How

ever

, suc

h pr

ior

cons

ent

shal

l no

t be

req

uire

d w

hen

the

Soci

ety

prov

ides

the

con

fiden

tial

info

r-m

atio

n to

a s

ubsi

diar

y.

11.4

The

Soc

iety

sha

ll ha

ve t

he r

ight

to

disc

lose

the

con

fiden

tial i

nfor

-m

atio

n if

requ

ired

to d

o so

und

er re

gula

tions

of t

he In

tern

atio

nal A

ssoc

ia-

tion

of C

lass

ifica

tions

Soc

ietie

s (IA

CS)

or a

ny s

tatu

tory

obl

igat

ions

.

12. I

NTE

LLEC

TUA

L PR

OPE

RTY

12

.1 E

ach

Party

exc

lusi

vely

ow

ns a

ll rig

hts

to i

ts I

ntel

lect

ual

Prop

erty

cr

eate

d be

fore

or

afte

r th

e co

mm

ence

men

t da

te o

f th

e C

ondi

tions

and

w

heth

er o

r not

ass

ocia

ted

with

any

con

tract

bet

wee

n th

e Pa

rties

.12

.2 T

he I

ntel

lect

ual

Prop

erty

dev

elop

ed f

or t

he p

erfo

rman

ce o

f th

e Se

rvic

es in

clud

ing,

but

not

lim

ited

to d

raw

ings

, cal

cula

tions

, and

rep

orts

sh

all r

emai

n ex

clus

ive

prop

erty

of t

he S

ocie

ty.

13. A

SSIG

NM

ENT

13.1

The

con

tract

res

ultin

g fro

m to

thes

e C

ondi

tions

can

not b

e as

sign

ed

or tr

ansf

erre

d by

any

mea

ns b

y a

Party

to a

third

par

ty w

ithou

t the

prio

r w

ritte

n co

nsen

t of t

he o

ther

Par

ty.

13.

2 Th

e So

ciet

y sh

all h

owev

er h

ave

the

right

to

assi

gn o

r tra

nsfe

r by

an

y m

eans

the

said

con

tract

to a

sub

sidi

ary

of th

e Bu

reau

Ver

itas

Gro

up.

14. S

EVER

AB

ILIT

Y 14

.1 I

nval

idity

of

one

or m

ore

prov

isio

ns d

oes

not

affe

ct t

he r

emai

ning

pr

ovis

ions

.14

.2 D

efin

ition

s he

rein

take

pre

cede

nce

over

oth

er d

efin

ition

s w

hich

may

ap

pear

in o

ther

doc

umen

ts is

sued

by

the

Soci

ety.

14.3

In

case

of

doub

t as

to

the

inte

rpre

tatio

n of

the

Con

ditio

ns,

the

Engl

ish

text

sha

ll pr

evai

l.

15. G

OVE

RN

ING

LA

W A

ND

DIS

PUTE

RES

OLU

TIO

N

15.1

The

Con

ditio

ns s

hall

be c

onst

rued

and

gov

erne

d by

the

law

s of

En

glan

d an

d W

ales

.15

.2 T

he S

ocie

ty a

nd t

he C

lient

sha

ll m

ake

ever

y ef

fort

to s

ettle

any

di

sput

e am

icab

ly a

nd in

goo

d fa

ith b

y w

ay o

f neg

otia

tion

with

in th

irty

(30)

da

ys f

rom

the

dat

e of

rec

eipt

by

eith

er o

ne o

f th

e Pa

rties

of

a w

ritte

n no

tice

of s

uch

a di

sput

e.15

.3 F

ailin

g th

at, t

he d

ispu

te s

hall

final

ly b

e se

ttled

by

arbi

tratio

n un

der

the

LCIA

rul

es, w

hich

rul

es a

re d

eem

ed to

be

inco

rpor

ated

by

refe

renc

e in

to th

is c

laus

e. T

he n

umbe

r of a

rbitr

ator

s sh

all b

e th

ree

(3).

The

plac

e of

ar

bitra

tion

shal

l be

Lond

on (U

K).

16. P

RO

FESS

ION

NA

L ET

HIC

S 16

.1 E

ach

Party

sha

ll co

nduc

t al

l act

iviti

es in

com

plia

nce

with

all

law

s,

stat

utes

, rul

es, a

nd re

gula

tions

app

licab

le to

suc

h Pa

rty in

clud

ing

but n

ot

limite

d to

: ch

ild l

abou

r, fo

rced

lab

our,

colle

ctiv

e ba

rgai

ning

, di

scrim

ina-

tion,

ab

use,

w

orki

ng

hour

s an

d m

inim

um

wag

es,

anti-

brib

ery,

an

ti-co

rrup

tion.

Eac

h of

the

Parti

es w

arra

nts

that

nei

ther

it, n

or it

s af

filia

tes,

ha

s m

ade

or w

ill m

ake,

with

res

pect

to th

e m

atte

rs p

rovi

ded

for

here

un-

der,

any

offe

r, pa

ymen

t, gi

ft or

aut

horiz

atio

n of

the

pay

men

t of

any

m

oney

dire

ctly

or

indi

rect

ly, t

o or

for

the

use

or b

enef

it of

any

offi

cial

or

empl

oyee

of t

he g

over

nmen

t, po

litic

al p

arty

, offi

cial

, or c

andi

date

.16

.2 In

add

ition

, the

Clie

nt s

hall

act c

onsi

sten

tly w

ith th

e So

ciet

y’s

Cod

e of

Eth

ics

of B

urea

u Ve

ritas

. ht

tp://

ww

w.b

urea

uver

itas.

com

/hom

e/ab

out-

us/e

thic

s+an

d+co

mpl

ianc

e/

1. IN

DEP

END

ENC

Y O

F TH

E SO

CIE

TY A

ND

APP

LIC

AB

LE T

ERM

S1.

1 Th

e So

ciet

y sh

all r

emai

n at

all

times

an

inde

pend

ent

cont

ract

or

and

neith

er th

e So

ciet

y no

r an

y of

its

offic

ers,

em

ploy

ees,

ser

vant

s,

agen

ts o

r su

bcon

tract

ors

shal

l be

or a

ct a

s an

em

ploy

ee, s

erva

nt o

r ag

ent o

f any

oth

er p

arty

her

eto

in th

e pe

rform

ance

of t

he S

ervi

ces.

1.

2 Th

e op

erat

ions

of

the

Soci

ety

in p

rovi

ding

its

Ser

vice

s ar

e ex

clus

ivel

y co

nduc

ted

by w

ay o

f ra

ndom

insp

ectio

ns a

nd d

o no

t, in

an

y ci

rcum

stan

ces,

invo

lve

mon

itorin

g or

exh

aust

ive

verif

icat

ion.

1.3

The

Soci

ety

acts

as

a se

rvic

es p

rovi

der.

This

can

not b

e co

nstru

ed

as a

n ob

ligat

ion

bear

ing

on t

he S

ocie

ty t

o ob

tain

a r

esul

t or

as

a w

arra

nty.

The

Soc

iety

is

not

and

may

not

be

cons

ider

ed a

s an

un

derw

riter

, br

oker

in

Uni

t’s

sale

or

ch

arte

ring,

ex

pert

in

Uni

t’s

valu

atio

n, c

onsu

lting

eng

inee

r, co

ntro

ller,

nava

l ar

chite

ct,

man

ufac

-tu

rer,

ship

build

er,

repa

ir or

con

vers

ion

yard

, ch

arte

rer

or s

hipo

wne

r; no

ne o

f the

m a

bove

list

ed b

eing

relie

ved

of a

ny o

f the

ir ex

pres

sed

or

impl

ied

oblig

atio

ns a

s a

resu

lt of

the

inte

rven

tions

of t

he S

ocie

ty.

1.4

The

Serv

ices

are

car

ried

out

by t

he S

ocie

ty a

ccor

ding

to

the

appl

icab

le R

ules

and

to

the

Bure

au V

erita

s’ C

ode

of E

thic

s. T

he

Soci

ety

only

is q

ualif

ied

to a

pply

and

inte

rpre

t its

Rul

es.

1.5

The

Clie

nt a

ckno

wle

dges

the

late

st v

ersi

ons

of th

e C

ondi

tions

and

of

the

appl

icab

le R

ules

app

lyin

g to

the

Serv

ices

’ per

form

ance

. 1.

6 U

nles

s an

exp

ress

writ

ten

agre

emen

t is

mad

e be

twee

n th

e Pa

rties

on

the

appl

icab

le R

ules

, th

e ap

plic

able

Rul

es s

hall

be t

he

rule

s ap

plic

able

at

the

time

of t

he S

ervi

ces’

per

form

ance

and

con

-tra

ct’s

exe

cutio

n.

1.7

The

Serv

ices

’ per

form

ance

is s

olel

y ba

sed

on th

e C

ondi

tions

. No

othe

r ter

ms

shal

l app

ly w

heth

er e

xpre

ss o

r im

plie

d.

2. D

EFIN

ITIO

NS

2.1

“Cer

tific

ate(

s)”

mea

ns c

lass

cer

tific

ates

, atte

stat

ions

and

repo

rts

follo

win

g th

e So

ciet

y’s

inte

rven

tion.

The

Cer

tific

ates

are

an

appr

aise

-m

ent

give

n by

the

Soc

iety

to

the

Clie

nt,

at a

cer

tain

dat

e, f

ollo

win

g su

rvey

s by

its

surv

eyor

s on

the

leve

l of c

ompl

ianc

e of

the

Uni

t to

the

Soci

ety’

s R

ules

or

to t

he d

ocum

ents

of

refe

renc

e fo

r th

e Se

rvic

es

prov

ided

. The

y ca

nnot

be

cons

trued

as

an im

plie

d or

exp

ress

war

ran-

ty o

f saf

ety,

fitn

ess

for t

he p

urpo

se, s

eaw

orth

ines

s of

the

Uni

t or o

f its

va

lue

for s

ale,

insu

ranc

e or

cha

rterin

g.

2.2

“Cer

tific

atio

n” m

eans

the

activ

ity o

f cer

tific

atio

n in

app

licat

ion

of

natio

nal

and

inte

rnat

iona

l re

gula

tions

or

stan

dard

s, i

n pa

rticu

lar

by

dele

gatio

n fro

m d

iffer

ent g

over

nmen

ts th

at c

an r

esul

t in

the

issu

ance

of

a c

ertif

icat

e.

2.3

“Cla

ssifi

catio

n” m

eans

the

clas

sific

atio

n of

a U

nit t

hat c

an re

sult

or n

ot i

n th

e is

suan

ce o

f a

clas

s ce

rtific

ate

with

ref

eren

ce t

o th

e R

ules

. 2.

4 “C

lient

” m

eans

the

Party

and

/or i

ts re

pres

enta

tive

requ

estin

g th

e Se

rvic

es.

2.5

“Con

ditio

ns”

mea

ns t

he t

erm

s an

d co

nditi

ons

set

out

in t

he

pres

ent d

ocum

ent.

2.6

“Ind

ustr

y Pr

actic

e” m

eans

Int

erna

tiona

l M

ariti

me

and/

or O

ff-sh

ore

indu

stry

pra

ctic

es.

2.7

“Int

elle

ctua

l Pr

oper

ty”

mea

ns a

ll pa

tent

s, r

ight

s to

inv

entio

ns,

utili

ty m

odel

s, c

opyr

ight

and

rela

ted

right

s, tr

ade

mar

ks, l

ogos

, ser

vice

m

arks

, tra

de d

ress

, bus

ines

s an

d do

mai

n na

mes

, rig

hts

in tr

ade

dres

s or

get

-up,

rig

hts

in g

oodw

ill o

r to

sue

for

pass

ing

off,

unfa

ir co

mpe

ti-tio

n rig

hts,

rig

hts

in d

esig

ns,

right

s in

com

pute

r so

ftwar

e, d

atab

ase

right

s, t

opog

raph

y rig

hts,

mor

al r

ight

s, r

ight

s in

con

fiden

tial

info

r-m

atio

n (in

clud

ing

know

-how

and

tra

de s

ecre

ts),

met

hods

and

pro

to-

cols

for

Ser

vice

s, a

nd a

ny o

ther

inte

llect

ual p

rope

rty r

ight

s, in

eac

h ca

se w

heth

er c

apab

le o

f re

gist

ratio

n, r

egis

tere

d or

unr

egis

tere

d an

d in

clud

ing

all a

pplic

atio

ns fo

r and

rene

wal

s, re

vers

ions

or e

xten

sion

s of

su

ch r

ight

s, a

nd a

ll si

mila

r or

equ

ival

ent r

ight

s or

form

s of

pro

tect

ion

in a

ny p

art o

f the

wor

ld.

2.8

“Par

ties”

mea

ns th

e So

ciet

y an

d C

lient

toge

ther

. 2.

9 “P

arty

” m

eans

the

Soci

ety

or th

e C

lient

. 2.

10

“Reg

iste

r”

mea

ns

the

regi

ster

pu

blis

hed

annu

ally

by

th

e So

ciet

y.

2.11

“R

ules

” m

eans

the

Soci

ety’

s cl

assi

ficat

ion

rule

s, g

uida

nce

note

s an

d ot

her

docu

men

ts.T

he R

ules

, pro

cedu

res

and

inst

ruct

ions

of t

he

Soci

ety

take

into

acc

ount

at t

he d

ate

of th

eir

prep

arat

ion

the

stat

e of

cu

rren

tly a

vaila

ble

and

prov

en t

echn

ical

min

imum

req

uire

men

ts b

ut

are

not

a st

anda

rd

or

a co

de

of

cons

truct

ion

neith

er

a gu

ide

fo

r m

aint

enan

ce,

a sa

fety

ha

ndbo

ok

or

a gu

ide

of p

rofe

ssio

nal

prac

tices

, all

of w

hich

are

assu

med

to b

e kn

own

in d

etai

l and

B

urea

u Ve

ritas

Mar

ine

& O

ffsho

re G

ener

al C

ondi

tions

-Ed

ition

Jan

uary

201

7

GUIDANCE NOTE NI 624

Risk-Based Structural Integrity Management ofOffshore Jacket Structures

SECTION 1 GENERAL

SECTION 2 RISK-BASED STRUCTURAL INTEGRITY MANAGEMENT OF OFFSHORE JACKET PLATFORMS

SECTION 3 SERVICE PROVISION

APPENDIX 1 TYPICAL PLATFORM’S DATA

April 2017

Section 1 General

1 General 5

1.1 Context1.2 Scope of the document1.3 Overview of API guidance1.4 Overview of the Society’s methods1.5 Organization of the document

2 References 6

2.1

3 Acronyms 6

3.1

Section 2 Risk-based Structural Integrity Management of Offshore Jacket Platforms

1 Introduction 8

1.1 General1.2 Inspection plan1.3 Risk reduction1.4 Benefits of risk-based approach for SIM1.5 Issues for jacket offshore structure1.6 Risk-based SIM framework

2 Collection of data 10

2.1 Purpose2.2 Typical data2.3 Source of data2.4 Quality of data

3 Risk assessment 11

3.1 General3.2 API risk categorization for existing platforms3.3 Factors to consider for specific risk assessment3.4 Risk ranking

4 Inspection plan 15

4.1 Definition of risk-based inspection plan4.2 Motives for risk-based inspection strategy4.3 Some knowledge from inspection experience4.4 Inspection frequency4.5 Inspection scope4.6 Inspection methods4.7 Deployment method

5 Risk reduction 18

5.1 General5.2 Exposure reduction5.3 Likelihood reduction

2 Bureau Veritas April 2017

6 Reassessment of the risk-based inspection strategy 20

6.1 General6.2 Significant change of the assessment premise6.3 After an inspection6.4 After the implementation of a mitigation strategy6.5 After a set of time period

7 Types of risk assessment 21

7.1 General7.2 Qualitative risk assessment7.3 Quantitative risk assessment7.4 Semi-quantitative risk assessment

8 Reporting on risk-based SIM 24

8.1 General8.2 Recommended content

9 Reference documents 24

9.1 API-RP-2SIM9.2 ISO 19901 - 99.3 Final report of the JIP on underwater inspection9.4 Final report of the JIP on SIM9.5 ISO 199029.6 API-RP-5809.7 API-581-BRD

Section 3 Service Provision

1 High level risk-based SIM method 29

1.1 General1.2 Method description1.3 Data gathering1.4 Likelihood of failure1.5 Consequence of failure1.6 Risk ranking1.7 Inspection planning

2 Risk-based SIM method for one jacket platform 32

2.1 General2.2 Method description2.3 Data Gathering2.4 Preliminary assessment2.5 Global risk level assessment2.6 Local risk levels assessment2.7 Inspection strategy

3 Fatigue-based probabilistic method 36

3.1 General3.2 Method description3.3 Data Gathering3.4 Risk acceptance criteria3.5 Tag system3.6 Fatigue analysis3.7 Pushover analysis3.8 Detailed RBI analysis3.9 Scheduling

April 2017 Bureau Veritas 3

Appendix 1 Typical Platform’s Data

1 Platform’s data 41

1.1 Characteristic data1.2 Condition data


NI 624, Sec 1

SECTION 1 GENERAL

1 General

1.1 Context

1.1.1 The API-RP-2SIM has emphasized the value of usingrisk-based approach to develop effective inspection strategyand program. It provides general guidelines to assign a riskcategory to a platform and details on the inspection strategyderived from the risk results. It sets out, also, the main factorsto consider in assessing platforms' risks when owner/opera-tors decide to adopt specific risk categorization e.g. detailrisk assessment techniques or complex risk matrices.

The Society contributed to the joint industry project for thedevelopment of the API-RP-2SIM. It has produced risk-based structural integrity methodologies for offshore jacketplatforms based on API recommendations. It has, also,developed a fatigue-based probabilistic method to deter-mine inspection frequency of tubular welds with higherlikelihoods of fatigue failure.

1.2 Scope of the document

1.2.1 This Guidance Note sets out the main recommenda-tions and requirements of the API-RP-2SIM for implement-ing a risk-based structural integrity management for offshorejacket platforms. It includes, also, relevant guidance fromother international standards and from reference reportsand papers.

The Society service offer is also presented. It includes meth-ods which apply, respectively, to a fleet of platforms, a plat-form unit and the structural components. It implements alltypes of risk assessment from qualitative to fully quantitative.

1.3 Overview of API guidance

1.3.1 The API-RP-2SIM includes guidance for risk-basedapproach to structural integrity management of offshorejacket platforms. It provides general guidelines for assigninga risk category to the platforms in terms of the exposure cat-egory and the likelihood of failure. The exposure category isdefined with respect to life safety exposure and conse-quence of failure including the environmental and the eco-nomic impact. A description of the relevant factors toconsider for determining the life safety exposure categoryand the level of consequence of failure is also given. Thestandard allows qualitative, semiquantitative, or fully quanti-tative methods to be used in assessing the level of likelihoodof failure. However no detail is given on how to implementthose methods. Only general guidelines are defined for theassessment of the likelihood of failure category.

The risk-based inspection strategy is specifically concernedwith the routine underwater inspections. However, itrequires that a baseline inspection was conducted and itshould use the findings from the above-water inspectionsand the eventual post-event inspections. The API-RP-2SIMgives detailed recommendations for determining inspectionstrategy from the risk categorization, including risk-basedinspection intervals and work scope, survey techniques anddeployment methods. Typical ranges of risk-based inspec-tion intervals are provided with respect to the platform risklevel along with a description of the inspection scope ofwork. The associated risk-based inspection program has tobe a minimum level II survey, according to the API classifi-cation of survey levels, but has to specify if higher surveylevels (e.g. level III and IV) are required.

When risk-based approach is not adopted, API provides adefault inspection program including pre-defined in-serviceinspection intervals and survey levels based on the expo-sure category only.

The recommended practice provides, in addition, generalguidelines on risk reduction options when a jacket platformis deemed as no longer fit-for-purpose.

1.4 Overview of the Society’s methods

1.4.1 The Society has developed three methods for riskassessment and inspection plan development as part of therisk-based structural integrity management of offshorejacket platforms, namely:• a high level risk-based SIM method• a risk-based SIM method for a jacket platform

• and a fatigue-based probabilistic method.

1.4.2 The high level method applies to a fleet of jacket plat-forms and uses a qualitative risk assessment method. Itallows a risk category to be assigned to each platform of afleet and inspection intervals and general inspectionrequirements to be developed based on the API guidanceand the inspection trends. The risk assessment methodserves as a mean to provide relative risk ranking of the plat-forms in a fleet, in order to identify the platforms most atrisk and which require more inspection focus or a detailedrisk analysis. It can also serve as a mean to compare giveninspection strategies in order to identify the best one withrespect to the risk impact or to another specific decision cri-teria adopted by owner/operators.

1.4.3 The risk-based SIM method for a jacket platform pro-vides a global risk assessment which allows inspectioninterval and inspection requirements based on API guid-ance to be defined. It provides also local risk ranking of theplatform's structural components, which allows, if required,the local inspections' scope of work to be defined. Theglobal risk assessment allows using of the qualitative


NI 624, Sec 1

approach of the high level method or structural analysisresults (e.g. reserve strength ratio) to develop inspectionplanning. The local risk ranking uses a semi-quantitativeapproach based on the results from in-place analysis andfatigue analysis. The method should be applied, followingthe high level method, on the platforms the most at risk andwhich require a more detailed risk analysis.

1.4.4 The fatigue-based probabilistic method uses a fullprobabilistic approach to develop inspection planning for aplatform's welded joints subject to fatigue. It requires afatigue analysis and several ultimate strength analyses to becarried out. The fatigue analysis allows the welded jointswith higher likelihood of fatigue failure to be identified. Theultimate strength analyses include a pushover analysis ofthe structure in its intact condition and pushover analyses ofthe structure in damage condition assuming a fatigue failureon the identified higher-fatigue welded joints taken sepa-rately. Structural reliability methods are used to computethe probabilities. The probabilities of fatigue failure of theselected welded joints and the probabilities of collapse fail-ure of the associated damaged structures are computed.Those probabilities are then combined to derive the proba-bility of collapse failure of the platform. The optimal inspec-tion plan is given by the one that minimizes the expectedoperational cost, including inspection and maintenancecost and failure cost. This method suits the jacket platformsfor which the welded joints that are critical for the structuralintegrity (e.g. end connections of primary members) arereported to have higher likelihood of fatigue failure.

1.5 Organization of the document

1.5.1 In addition to the current introductive section, thisGuidance Note includes two sections. The first oneaddresses the key elements the risk-based SIM of offshorejacket structures according to the API-RP-2SIM supple-mented with relevant guidelines from other internationalstandards and reference reports and papers. The second onepresents the Society service provision, including the highlevel SIM method, the SIM method for one jacket platformand the fatigue-based probabilistic method.

2 References

2.1

2.1.1

a) API-RP-2SIM, Structural Integrity Management of FixedOffshore Structures, 1st ed., Washington: API PublishingServices, 2014.

b) API-RP-2A-WSD, Recommended Practice for Planning,Designing and Constructing Fixed Offshore Platforms-Working Stress Design, 22nd ed., Washington: API Pub-lishing Services, 2014.

c) API-RP-2A-WSD, Recommended Practice for Planning,Designing and Constructing Fixed Offshore Platforms-Working Stress Design, 21st ed., Washington: API Pub-lishing Services, 2000.

d) API-RP-580, Risk-Based Inspection Technology, 2nd ed.,Washington: API Publishing Services, 2009.

e) API-RP-581, Risk-Based Inspection Technology, 2nd ed.,Washington: API Publishing Services, 2008.

f) API-581-BRD, Base Ressource Document - Risk-BasedInspection Technology, 2nd ed., Washington: API Pub-lishing Services, 2000.

g) ISO 19902:2007, Petroleum and natural gas industries -Fixed steel offshore structures, ISO, Ed., Geneva: ISO,2007.

h) ISO 19901-9, Structural integrity management Offshorestructures, ISO, under preparation.

i) MSL, "Rationalization and Optimization of UnderwaterInspection Planning consistent with API-RP-2A section14": JIP Final Report, 2000.

j) Atkins, "Development of Guidance on Structural Integ-rity Management of Fixed Offshore Structures": JIP FinalReport, 2011.

k) Nelson A., Technical Performance Measures for NorthSea Jacket Structures, HSE Research report, 2003.

l) DeFranco S., O'Connor P., Tallin A., Roy R. and PuskarF., Development of a Risk Based Underwater Inspection(RBUI) Process for Prioritizing Inspections of LargerNumbers of Platforms, OTC 10846, 1999.

m) Turner J. W., Wisch D. J. and Guynes S. J., A Review ofOperations and Mitigation Methods for Offshore Plat-forms, OTC 7486, 1994.

n) Faber, M. H,. Risk-based inspection: The framework.Structural engineering international, 12(3), 186-195,2002.

o) Goyet J., Boutillier V. and Rouhan A., Risk-basedInspection for Offshore Structures, Ships and OffshoreStructures, 8 (3-4), 303-318, 2013.

3 Acronyms

3.1

3.1.1 ACFM : Alternating Current Field MeasurementACPD : Alternative Current Potential Drop

API : American Petroleum InstituteCoF : Consequence of failureCP : Cathodic Protection

CVI : Close Visual InspectionECD : Eddy Current DetectionETA : Event Tree Analysis

FEM : Finite Element ModelFFP : Fitness-For-Purpose

FMD : Flooded Member DetectionFORM : First Order Reliability MethodFTA : Fault Tree Analysis

GPS : Global Positioning SystemGVI : General Visual InspectionHAZID : HAZard IDentification

JIP : Joint Industry ProjectLAT : Lowest Astronomical Tide


NI 624, Sec 1

LoF : Likelihood of FailureMPI : Magnetic Particle InspectionNDT : Non Destructive TestingPA : Phase ArrayPLL : Potential Loss of LifePOB : Personnel On BoardPoD : Probability of DetectionPoF : Probability of FailureQRA : Quantitative Risk AssessmentRAC : Risk Acceptance CriteriaRAO : Response Amplitude Operator

RBI : Risk-Based Inspection

ROC : Receiver Operating Curve

ROV : Remote Operating Vehicle

RP : Recommended Practice

RSR : Reserve Strength Ratio

RT : Radiographic Technique

SCF : Stress Concentration Factor

SIM : Structural Integrity Management

SMR : Strengthening Modification and Repair

TOFD : Time of Flight Diffraction.


NI 624, Sec 2

SECTION 2 RISK-BASED STRUCTURAL INTEGRITY MANAGEMENT OF OFFSHORE JACKET PLATFORMS

1 Introduction

1.1 General

1.1.1 Risk-based SIM uses risk analysis to develop SIMstrategy, including inspection strategy and risk reductionmeasures, with respect to the actual risk level.

1.2 Inspection plan

1.2.1 The overall inspection plan for offshore jacket struc-tures includes the following types of inspections:

• routine above-water inspections to evaluate the condi-tion of the platform topsides and which should be con-ducted on an annual basis

• a baseline underwater inspection to determine the as-installed condition of the platform

• routine underwater inspections to evaluate the condi-tion of the underwater portion of the platform andappurtenances

• and special or post-event inspections to determine thecondition of the platform after events such as extrememetocean event or collision.

Among them, only the routine underwater inspections canbe driven by the platform risk level. However, implement-ing risk-based routine underwater inspections requires thata baseline inspection was conducted and should take intoconsideration data from the other inspections types e.g.above-water inspections and post-event inspections.

A risk-based routine underwater inspection provides:

• an inspection interval or a next inspection date consis-tent with the platform risk level

• the inspection coverage

• the inspection techniques to be used

• and the expected residual level of risk after inspectionor the mitigation actions.

In particular, inspection coverage can specify the criticalstructural details from a risk point of view and which haveto be inspected or a percentage of structural details to beinspected in order to provide representative condition dataon the overall structure.

1.3 Risk reduction

1.3.1 Whenever the estimated risk level for the platform ishigher than an acceptable limit, modifications on the plat-form should be considered to reduce this risk level. Twocategories of risk reduction measures can be carried out:

• Exposure mitigation e.g. reduction of hydrocarboninventory, reduction of the manning level

• Likelihood reduction e.g. deck load reduction, global orlocal strengthening.

1.4 Benefits of risk-based approach for SIM

1.4.1 Risk-based approaches allow owners/operators todevelop inspection strategies which prioritized the struc-tural items the most at risk. This results in:

• an overall reduction in risk

• a cost optimization as the approach aims at providingan effective inspection plan

• an effective data collection as data need not be col-lected for all the structural items but higher priorityshould be given to those more at risk. Thus, more effortcan be spent on those structural items, which allowsmore accurate information to be collected

• and an understanding and acceptance of current risk asthe approach is based on the assessment of the currentcondition of the structure under study.

1.5 Issues for jacket offshore structure

1.5.1 The implementation of a risk-based approach for theSIM of jacket offshore structures raises some specific issues,described in the following sections.

1.5.2 Availability of the platform's data

Some useful data (e.g. fabrication and installation data,baseline inspection records or other previous inspectionrecords) may not be available, especially for ageing plat-forms. This is mostly because those records don't exist orbecause the operator is not aware of what data he has,where those data are being kept and who is in charge ofdata management.

There are two main ways to deal with missing data:

• The first and recommended option is to consider surveyto collect the necessary information. This option is moreexpensive but it will provide accurate data on the plat-form condition and allow for an accurate risk levelassessment.


NI 624, Sec 2

• The second one is to perform the risk analysis usingappropriate conservative assumptions where the infor-mation is missing. This option is simple but could resultin a rough risk assessment.

1.5.3 Accuracy of the risk assessment

Platform collapse failures are rare events. Therefore, thereare little data to develop comprehensive collapse failurestatistics of jacket platforms like other items such asmachinery or equipment.

In an attempt to compute the risk level accurately, model-based quantitative methods are used. However, these meth-ods usually require more data and more computationaleffort. Moreover, care should be taken in formulating themodel of the damage mechanism and in selecting the prob-abilistic distributions that represent the uncertaintiesinvolved. It is usually recommended that a knowledgeableperson be involved in implementing such methods.

Most often a relative risk ranking approach is used. It con-sists in assessing the risk level based on experience withother structures taken as a benchmark. In this case, detailedquantitative assessment is not necessary, but simply assign-ing scores to the structural items with respect to relevant fac-tors that influence the risk level can be well enough. Thescoring process can be carried out in a systematic way witha dedicated mathematic formulation or by gathering experts'opinion through dedicated workshops or meetings. Even ifthis relative risk ranking does not allow the ideal inspectionstrategy to be determined, it shows on what structural itemsthe risk management effort should focus: the higher rankedones.

1.5.4 Relationship between risk level and inspection frequency

There is no objective means to link the results of a relativerisk ranking assessment to an inspection plan, especially toan inspection frequency, as the risk values are not absolute.In this case, risk-based inspection strategies rely on:

• standards' requirements or recommendations, whichgather the good practices of the dedicated industry

• and experts' opinion, who could provide inspectionstrategies all the more suitable as their level of expertiseis higher.

However, relative ranking can allow different inspectionstrategies to be compared, by simply measuring theirrespective risk impacts, in order to find the best one. In thiscase, the ability of the risk ranking process to properly com-pare inspection strategies should be validated first.

1.6 Risk-based SIM framework

1.6.1 The overall SIM process consists of four primary ele-ments: DATA, EVALUATION, STRATEGY and PROGRAM(see Fig 1):

• DATA relates to the implementation of a data manage-ment system for collecting, compiling and updating theplatforms' data.

• EVALUATION aims at assessing the impact that newplatforms' data have on the structural integrity and leadsto carry out risk categorization and structural analysisfor the assessment of fitness-for-purpose and to considerrisk reduction actions when the estimated risk level ishigher than an acceptable limit.

• STRATEGY relates to the development and the imple-mentation of inspection strategy and possibly risk reduc-tion actions from the results of the evaluation step.

• PROGRAM refers to the execution of the inspection andthe possible risk reduction scope of work, including therequirements for the recording and the reporting of theinspection findings.

The SIM process provides the opportunity for owners/opera-tors to adopt risk principles to develop in-service inspectionstrategy according to the framework depicted in Fig 2.

Figure 1 : SIM process

DATA EVALUATION STRATEGY PROGRAM

Managed systemfor the archivaland retrieval ofSIM data andother pertinent

records

Evaluation ofstructural integrity

and fitness-for-purpose:

development ofremedial actions

Overall inspectionphilosophy and

strategy andcriteria for in-

service inspection

Detailed work scope for inspection

activities andoffshore execution

to obtainquality data


NI 624, Sec 2

Figure 2 : Framework for developing risk-based in-service inspection strategy

However, before starting the risk-based SIM frameworkitself, some key issues have to be addressed:

• The objectives of the risk assessment should be clearlystated (e.g. risks understanding, reducing costs, estab-lishing risk criteria).

• The team involved in the risk-based SIM process has tobe formed and the competencies, roles and account-abilities of its members have to be defined.

• The scope of the risk-based SIM should be defined. Risk-based SIM could be applied to a fleet or to a platformincluding eventually its individual structural details. Forthis purpose, an initial screening could be performed toidentify the structural items that are most susceptible tofailure under the design event. Those structural items canbe a group of platforms when the analysis is performed ata fleet level or a group of structural details when the anal-ysis is performed for one platform only.

• The settings of the risk-based SIM have to be defined,namely:

- the applicable standards or codes

- the inspection plan period

- and the period of validity of the results and whenthey have to be revisited.

• A type of risk assessment should be selected (e.g. quali-tative or quantitative) with respect to the objective of therisk assessment.

• The resources and time required have to be estimated.

2 Collection of data

2.1 Purpose

2.1.1 The collection of data and information aims at pro-viding the necessary input:

• to assess the potential factors and their respective influ-ence on the platform's susceptibility to failure

• to give values to the required inputs for the calculationof the likelihood and consequence of failure

• to assist in inspection planning.

2.2 Typical data

2.2.1 SIM data are divided into two broad categories: plat-form's characteristic data and platform's condition data:• The platform's characteristic data is the baseline data

that represents the structure at installation. The charac-teristic data includes:- general platform data- design data- fabrication data- and installation data.

• The platform condition data represents the changes tothe characteristic data that may occur during the life ofthe platform. The condition data includes the following:- in-service inspection data- damage evaluation data- corrosion protection data- SMR data- platform modifications- condition monitoring data- and operational incident data.

The list of typical platform's data for the SIM process pro-vided in the API-RP-2SIM is repeated in appendix for infor-mation.

2.3 Source of data

2.3.1 The main sources of data are the following:• design report including initial drawings• fabrication report• installation report• most recent engineering assessment report including

drawings• site conditions report including metocean climate data

and soil data• in-service inspections records• cathodic protection records• incidents investigation reports

Risk reductionactions

(if required)Inspection plan

Reassessment

Risk ranking

Consequenceof failure

Likelihoodof failure

Collectionof data

Risk assessment


NI 624, Sec 2

• modification, strengthening and repairs records

• industry or in-house failure data.

If other risk/hazard analysis results are available, they mayprovide valuable data to the risk analysis for the SIM, e.g.process QRA consequence analysis.

2.4 Quality of data

2.4.1 In order to ensure relevant risk analysis:

• up-to-date data should be used including most recentengineering assessment report and last inspection records

• the input data should be validated by knowledgeablepersons to avoid abnormal data or inaccurate inspectionmeasurement to be used

• the potential impact of the conservative assumptionsmade in case of missing or incorrectly measured datahas to be understood

• sensitivity analysis should be carried out whenever pos-sible to identify the data, the uncertainties of whichaffect more the risk results and which need more care

• and reference to the standards and codes which wereused for design and for in-service inspection should bemade, as they might contain requirement for ensuringquality of data.

3 Risk assessment

3.1 General

3.1.1 Risk is defined according to API-RP-2SIM as the com-bination of the likelihood of some event occurring during atime period of interest (e.g. one year) and the consequences(generally negative) associated with the event.

Sometimes the terms probability or frequency are used,instead of likelihood. Likewise, the term severity is used,instead of consequence.

The API-RP-2SIM defines the failure of a jacket platform asthe collapse of the platform or its inoperability as the resultof the occurrence of an extreme design event (e.g. extremestorm, hurricane, ice movement or earthquake, etc.). Thefactors that could render a jacket platform vulnerable to itsextreme design event are

• an accidental event (e.g. fire, blast, vessel impact,dropped object,…)

• or the degradation of one or many structural components(especially primary structural components) by fatigue orcorrosion.

Risk-based in-service inspections intend to control specifi-cally the second type of failure cause. However, data fromaccidental events that have occurred should also be consid-ered, if they exist, in defining the frequency and scope ofrisk-based in-service inspections.

API-RP-2SIM provides general guidelines for assigning a riskcategory to a given platform. Owner/operators may decideto adopt more detailed risk categorization. This requiresfactors relevant for the platforms' susceptibility to failureand for the impact of failure to be considered.

3.2 API risk categorization for existing plat-forms

3.2.1 API defines a general risk categorization for existingplatforms as the product of their exposure category andtheir likelihood of failure category.

3.2.2 Exposure categoriesThe exposure category of an existing platform is given interms of life safety exposure categories and consequence offailure categories, accounting for possible environmentalconsequence and economic losses. It should be determinedby the more restrictive of either life safety or consequence offailure using the exposure category matrix provided in Tab 1.

Table 1 : Exposure category matrix

The life safety exposure should consider the maximumanticipated environmental event that would be expected tooccur while personnel are on the platform. It is divided intothree main categories:

• S-1: Manned-Nonevacuated category refers to a plat-form that is continuously (or nearly continuously) occu-pied by persons accommodated and living thereon andfrom which personnel evacuation prior to the designenvironmental event (e.g. winter storms, sudden hurri-canes, and earthquakes) is either not intended orimpractical.

• S-2: Manned-Evacuated category refers to a platformthat is normally manned except during a forecast designenvironmental event and requires that all of the follow-ing hold:

- reliable forecast of design environmental event andweather condition before the occurrence of suchevent not likely to inhibit an evacuation

- planned evacuation prior to a design environmentalevent

- sufficient time and resources to safely evacuate theactual platform and all other platforms likely torequire evacuation.

• S-3: Unmanned category refers to a platform that is notnormally manned or a platform that is not classified aseither manned-nonevacuated or manned-evacuated e.g.emergency shelters.

The consequence of failure should consider the anticipatedimpact to the environment, and the possible economicimpact through losses to the owner (platform and equip-ment repair or replacement, lost production, etc), the antic-

Life safety category

Consequence of failure category

C-1 High

C-2 Medium

C-3 Low

S-1 Manned - nonevacuated L-1 L-1 L-1

S-2 Manned - evacuated L-1 L-2 L-2

S-3 Unmanned L-1 L-2 L-3

L-1 : HighL-2 : MediumL-3 : Low


NI 624, Sec 2

ipated losses to other operators (lost production throughtrunk lines), and anticipated losses to industry and govern-ment. It is divided into three main categories:

• C-1: High Consequence of Failure category refers to:

- major platforms and/or those platforms that have thepotential for well flow of either oil or scour gas inthe event of failure

- platforms where the shut-in of the oil or scour gasproduction is not planned or not practical prior theoccurrence of the design environmental event

- and platforms that support major transport linesand/or storage facilities for intermittent oil shipment

• C-2: Medium Consequence of Failure category refers toplatforms that would be shut-in during the design eventand requires that:

- all wells, that could flow on their own in the eventof platform failure, contain fully functional subsur-face safety valves (SSVs) compliant with API specifi-cations

- oil storage is limited to process inventory and surgetanks to pipeline transfer.

• C-3: Low Consequence of Failure category refers tominimal platforms where production would be shut-induring design event and requires that:

- all wells, that could flow on their own in the eventof platform failure, contain fully functional subsur-face safety valves (SSVs) compliant with API specifi-cations

- oil storage is limited to process inventory.

3.2.3 Likelihood of failure categories

The likelihood of failure of a platform depends on key struc-tural characteristics e.g. the deck elevation, structural con-figuration given by the number of legs and the bracingsystem, while existing damage or deterioration may indicatea reduction in the platform's strength, thus an increase inthe platform's likelihood of failure.

The API allows qualitative, semiquantitative or quantitativemethods to be used in categorizing the likelihood of failureof a platform. However, no specific guidance is provided toimplement such methods, but general guidelines aredefined for three categories of likelihood of failure.

• The High Likelihood category refers to platforms that arelikely to fail in the design event, meaning that theirreserve strength ratio (RSR) against the 100-year envi-ronmental design event is less than 1 in their presentcondition and overload may lead to wave-in-deck load.

• The Medium Likelihood category refers to platforms thatare not expected to fail in the design event (with a RSRlarger than 1), but which can sustain damage thatrequires inspections after occurrence of the environ-mental design event.

• The Low Likelihood category refers to platforms that arevery unlikely to fail in the design event (with sufficientreserve strength) and are tolerant to any damage or over-load that does occur in the environmental design event.

3.2.4 Risk matrix

The risk matrix may be used to present the risk categoriza-tion results. Generally, its rows represent the likelihood offailure categories while its columns represent the exposurecategories. It is sectored into regions corresponding to riskcategories.

The API provides an example 3 x 3 risk matrix (Tab 2) withsymmetrical risk categories that can be used for platformsrisk categorization as follows:

• Risk Level 1 refers to platforms that should be consid-ered for a major focus of resource, including anincreased inspection frequency and intensity and/ormore detailed engineering.

• Risk Level 2 refers to platforms that should be consid-ered for a moderate focus of resource.

• Risk Level 3 refers to platforms that should be consid-ered for a less focus of resource, including a reducedinspection frequency and scope.

Table 2 : Risk categorization matrix example

3.3 Factors to consider for specific risk assessment

3.3.1 General

Owner/operators may decide to adopt specific risk categori-zation e.g. further subdivide exposure and likelihood of fail-ure categories to adopt a more complex risk matrix or usedetailed risk assessment techniques. General guidance isprovided in the sequel on the factors to consider when aspecific risk assessment is to be set up.

3.3.2 Likelihood of failure factors

Three basic elements have the potential to influence thelikelihood of failure of a jacket platform:

• the expected extreme loads over the platform's lifetimeor service life

• the strength or capacity to bear those extreme loads

• the management system of inspection, analysis andrepair.

In fact, a change in the anticipated extreme load such as alower deck elevation or an increase in the topside load mayincrease the likelihood of failure. Likewise, existing damageor deterioration may reduce the system capacity, and there-fore, may increase the likelihood of failure. The manage-ment system of inspection, analysis and repair reflect theability of the owner/operator to detect existing damage forexample; thus a poor management system increase theuncertainties in the detection of such damage, which maylead to an increase in the likelihood of failure.

Exposure category

Likelihood category

Low Medium High

High Risk level 2 Risk level 1 Risk level 1

Medium Risk level 3 Risk level 2 Risk level 1

Low Risk level 3 Risk level 3 Risk level 2


NI 624, Sec 2

Therefore, the assessment of the likelihood of failure shouldbe based on relevant factors that affect the platformstrength, the expected extreme loads and the managementsystem in place.

• The jacket platform strength may be affected by the fol-lowing factors:

- the deck height

- the framing configuration

- the number of legs

- the water depth

- the foundation stability (e.g. piles, grouted piles,mudmat)

- the existing damages and/or deterioration

- the scour

- the debris

- and the performance of the corrosion protection sys-tem.

• The loads applied to the jacket platform are affected bythe following factors:

- the operational metocean loads (e.g. wave, wind,tides, currents and ice)

- the extreme metocean loads

- the platform orientation

- the platform weight

- the equipment and material layouts

- the size and the number of appurtenances (e.g. ris-ers, conductors)

- the active geological processes (e.g. earthquakes,fault planes, seafloor instability, shallow gas)

- and the marine growth.

• The performance of the management system to inspec-tion, analysis and repair is usually evaluated through aquestionnaire and is affected by the following factors:

- the asset integrity management (AIM) and thehealth, safety and environment (HSE) policy

- the existing procedure for inspection, repair andanalysis as well as for the qualification of personnelinvolved in such activities

- existing management of change (MOC) process

- existing data management system and availability ofplatform's characteristic and condition data, includ-ing design, fabrication, installation and inspectionsdata

- the level of confidence in structural analysis results.

3.3.3 Assessment of the likelihood of failureThe assessment of the likelihood of failure accounts for:• the as-installed condition of the platform which repre-

sents the baseline likelihood of failure• the present condition of the platform• the history of maintenance carried out on the platform• and the analysis results and assumptions for the subse-

quent structural assessment to the original design.

The baseline LoF is assessed with respect to:• the original design criteria in terms of the strength and

loads factors listed above, including the degree of con-servatism in the metocean criteria and the degree ofstructural redundancy

• the structural analysis results and assumptions from theoriginal design

• the inspection findings and the strengthening modifica-tion and repair (SMR) carried out during fabrication,transport and installation and their effects on thestrength factors.

Then, the present condition and the maintenance historyadjust the baseline LoF accounting for the effects of the cur-rent values of the strength and loads factors compared totheir design values.

When the available data allow it, one uses comparison ofthe actual platform to reference's ones in the assessment ofLoF. In this case, one can consider:• the platform age in comparison to recent platforms• the original design code in comparison to current

design practices• learning from other similar platforms.

3.3.4 Consequence of failure factorsThe consequence of failure is the impact that a platformfailure has on:• the health and safety• the environment• the business• and the company reputation.

In order to evaluate the CoF, the following factors have tobe considered:• the platform functionality or type• the manning level or the number of personnel on board• the platform location e.g. distance to the shoreline• the production rate• and the anticipated financial costs due to production

lost, cleanup, replacing the platform and redrillingwells, etc.

3.3.5 Assessment of the consequence of failureThe value of the CoF measures the level or the significanceof the impact of failure. Its evaluation is relatively easier in arisk-based SIM study than in a traditional risk analysis forwhich a detailed consequence analysis is required. • When a qualitative risk assessment is adopted, descrip-

tive qualitative values are assigned and the overall CoFrating is the most conservative in terms of safety, envi-ronment or economic consequences.


NI 624, Sec 2

3.4 Risk ranking

3.4.1 Once LoF and CoF are developed, the risk rankingprocess consists in rating the platforms' risk levels fromlower to higher risk levels with respect to LoF and CoF.

The results of the risk ranking are presented in simple for-mats to decision-makers and inspection planners to helpthem prioritizing the inspection efforts. The common for-mats are the risk matrix, the risk plot and the risk indextable.

For the purpose of inspection planning, the risk levels arecategorized. There is a general consensus on the criteria tocategorize the risk to safety and environment and such cate-gories are set out in dedicated standards. However, forfinancial risks, companies generally will develop their owncriteria. Cost-benefit analysis is a useful mean to achievethis.

3.4.2 Risk matrix

The risk matrix is very effective mean to present the riskranking results. It uses a categorization of the LoF and theCoF. The platforms' risk levels are positioned into the boxesof the risk matrix. Different sizes of matrices may be used(e.g. 3 x 3, 5 x 5, etc.) along with different numbers of riskcategories (e.g. 3, 5, etc.).

The risk matrix is sectored into regions corresponding to riskcategories. Many risk matrix format can be encountereddepending on the risk acceptance criteria. Fig 3 showssome typical examples of risk matrix format. A symmetricalrisk matrix gives the same weight to both LoF and CoF. Anunsymmetrical risk matrix assigns especially more weight toCoF to reflect the risk aversion of a company. Special riskmatrix format may be adopted that may classify the boxhaving lowest LoF and highest CoF in critical risk region toreflect the fact that lower LoF are usually inaccurately esti-mated and therefore high consequence structures withlower LoF are to be classified into the critical risk region.

Table 3 : Example of risk index table

3.4.3 Risk plotThe risk plot is better suited to present the risk rankingresults, should numerical risk values be more meaningful tothe stakeholders. It is often drawn using log-log scalesallowing categorizing the risk levels with iso-risk lines. (SeeFig 4).

3.4.4 Risk index tableThe risk rankings can also be displayed in terms of a riskindex in a tabular form (Tab 3). The risk index is the ratio ofthe actual risk level to the acceptable risk threshold allow-ing the risk levels to be simply categorized with respect tothat acceptable risk threshold.

Figure 3 : Example of risk matrix formats: (a) symmetrical, (b) unsymmetrical, (c) special

Platform LoF CoFRisk level

Risk index

Cate-gory

P − 7 100 83 8283 0,83 V

P − 18 93 88 8132 0,81 V

P − 17 97 79 7671 0,77 IV

P − 9 75 97 7231 0,72 IV

P − 4 76 94 7179 0,72 IV

P − 13 65 98 6371 0,64 III

P − 1 99 52 5159 0,52 III

P − 16 58 77 4433 0,44 II

P − 19 89 40 3597 0,36 II

P − 11 31 87 2675 0,27 I

P − 14 22 91 2017 0,20 I

P − 8 54 33 1775 0,18 I

P − 6 18 81 1443 0,14 I

P − 10 78 15 1151 0,12 I

P − 5 77 9 663 0,07 I

P − 15 7 77 537 0,05 I

P − 2 5 60 292 0,03 I

Risk-Based Structural Integrity Management of Offshore...

Documents

Transcript of Risk-Based Structural Integrity Management of Offshore...