NATIONAL CENTER FOR SCIENTIFIC RESEARCH “DEMOKRITOS” LAB. OF SYSTEMS RELIABILITY AND INDUSTRIAL SAFETY INSTITUTE OF NUCLEAR TECH. RADIATION PROTECTION

NATIONAL CENTERFOR SCIENTIFIC RESEARCH“DEMOKRITOS”

LAB. OF SYSTEMS RELIABILITYAND INDUSTRIAL SAFETY

INSTITUTE OF NUCLEAR TECH. RADIATION PROTECTION

IRISK: DEVELOPMENT OF AN INTEGRATED TECHNICAL AND MANAGEMENT RISK

METHODOLOGY FOR CHEMICAL INSTALLATIONS

O. N. Aneziris

PRISM SEMINAR 27 May 2004 SLOVAKIA




I-RISKI-RISKDEVELOPMENT OF AN DEVELOPMENT OF AN INTEGRATEDINTEGRATED TECHNICAL AND TECHNICAL AND

MANAGEMENT RISK CONTROL AND MONITORINGMANAGEMENT RISK CONTROL AND MONITORINGMETHODOLOGY FOR MANAGING AND QUANTIFYING ON-SITEMETHODOLOGY FOR MANAGING AND QUANTIFYING ON-SITE

AND OFF-SITE RISKSAND OFF-SITE RISKS

EC Contract No: ENVA-CT96-0243

Ministry of Social Affairs and Employment (SZW), The Netherlands (Coordinator)Four Elements Ltd, UK (Secretariat)

Health and Safety Executive, UKMinistry of Environment (VROM), The Netherlands

NCSR Demokritos, GreeceNational Institute for Health and Environment (RIVM), The Netherlands

Norsk Hydro, NorwaySafety Science Group, Delft University of Technology, The Netherlands

SAVE Consulting Scientists, The Netherlands




OUTLINE

IntroductionTechnical modelManagement modelModification of Loss Of Containment

frequency, according to the Safety Management System

Case studies




I-RISK

TECHNICAL MODEL

PARAMETERSPARAMETERS(λ, μ,T, fM, TM,QM1)

MANAGEMENT MODEL




HAZARD IDENTIFICATIONHAZARD IDENTIFICATION

MODELLING OF ACCIDENTSMODELLING OF ACCIDENTS

ACCIDENT SEQUENCESACCIDENT SEQUENCESPLANT DAMAGE STATESPLANT DAMAGE STATES

FREQUENCY FREQUENCY ESTIMATIONESTIMATION

CONSEQUENCE CONSEQUENCE ASSESSMNETASSESSMNET

RISK INTEGRATIONRISK INTEGRATION




TECHNICAL MODEL

MASTER LOGIC DIAGRAM

EVENT TREE - FAULT TREE ANALYSIS

CONSEQUENCE ANALYSIS

RISK INTEGRATION




MASTER LOGIC DIAGRAM (MLD)

MLD FORMS THE BASIS OF THE TECHNICAL MODEL

MLD IS NOT A FAULT TREE

MLD PROVIDES THE STARTING POINT FOR DEVELOPING PLANT-SPECIFIC MODELS

MLD IDENTIFIES INITIATING EVENTS

LOSS OF LOSS OF CONTAINMENTCONTAINMENT

STRUCTURAL STRUCTURAL FAILUREFAILURE

LOSS OF LOSS OF BOUNDARY BOUNDARY

CONTAINMENT CONTAINMENT BYPASSBYPASS

ERROSION HIGH TEMPERA

TURE

UNDERPRESUNDERPRESSURESURE

VIBRATIVIBRATIONON

EXTERNAL EXTERNAL LOADINGLOADING

CORROSION OVERPRESSURE

FLOODINGFLOODINGSNOW, ICESNOW, ICE SEISMICSEISMIC HIGH HIGH WINDSWINDS

DIRECT DIRECT PRESSURE PRESSURE INCREASE INCREASE FROM GASFROM GAS

COOLING COOLING MALFUNCTMALFUNCT

IONION

EXCESS EXCESS HEATHEAT

OVRFILLINGOVRFILLING

INTERNALINTERNAL EXTERNAL

CHEMICAL CHEMICAL INCOMPATIINCOMPATI

BLE BLE MATERIALMATERIAL

RUN AWAY RUN AWAY REACTIONREACTION

COMBUSTICOMBUSTIONON

MASTER LOGIC DIAGRAM FOR LOSS OF CONTAINMENT

EXCESS EXCESS TEMPERATTEMPERAT

UREURE

LOW LEVELLOW LEVEL LOW LOW TEMPERATTEMPERAT

UREURE

NATURAL NATURAL PHENOMENAPHENOMENA

SUPPORTS SUPPORTS FAILFAIL

EXTRA EXTRA LOADSLOADS

ROLL OVERROLL OVER PRESSURE PRESSURE SHOCH IN SHOCH IN

HOSEHOSE

INTERNAL INTERNAL PRESSURE PRESSURE INCREASEINCREASE

CONTAINCONTAINMENT MENT

OPENEDOPENED

CONTAINCONTAINMENT MENT OPENSOPENS




EVENT TREE - FAULT TREE EVENTS

A) INITIATING EVENTS (fi, λ, fHi)

B) COMPONENT - BASIC EVENTS

PERIODICALLY TESTED STANDBY COMPONENT

NONTESTED

REPAIRABLE ON LINE COMPONENT

NON REPAIRABLE

C) HUMAN ACTIONS




AVERAGE UNAVAILABILITY FOR DIFFERENT TYPES OF COMPONENTS

PERIODICALLY TESTED COMPONENTSi) Unavailability owing to hardware failure between tests:failure rate T: mean time between testsιι) Unavailability owing to repair of detected failures λ: failure rate TR: duration of the repair T: mean time between tests

U T1

12

ιιi)Unavailability owing to routine maintenance fM: frequency of maintenance TM: duration of the maintenance

U T TR2

1

2

U U f Tm m3 2

U U Q QM M4 3 1 2 ιv)Unavailability owing to maintenance QM1: prob. of commiting an error QM2: prob. of not detecting an error




PARAMETERS OF TECHNICAL MODEL fi FREQUENCY OF INITIATING EVENTS

λs FAILURE RATE IN STANDBY MODE

T PERIOD OF TESTING

TR DURATION OF REPAIR

QM1 ERROR IN TEST AND REPAIR

QM2 FAILURE TO DETECT PREVIOUS ERROR

fM FREQUENCY OF ROUTINE MAINTENANCE

TM DURATION (MEAN) OF ROUTINE MAINTENANCE

λO FAILURE RATE OF ON-LINE COMPONENTS

μ REPAIR RATE OF ON-LINE COMPONENT

QO1 PROBABILITY OF NOT PERFORMING ACTION

QO2 PROB. OF NOT DETECTING/ RECOVERING ERROR




FREQUENCY OF LOSS OF CONTAINMENT

ffLOCLOC=g(=g(bb))

bb=u(=u(qq))

bb: vector of basic events: vector of basic eventsqq: vector of technical parameters: vector of technical parameters




MODIFICATION OF THE FREQUENCY OF LOC ACCORDING TO THE SMS

ln fj=ln fl + (ln fu-ln fl) mj/10

fj modified value of the jth technical parameter

fl lower value of each parameter, for the instal-

lation with the poorest SMS in the industry

fl upper value of each parameter, for the instal-

lation with the best SMS in the industry

mj modification factor of the jth technical parameter

ln fu

10

0

ln fl




MANAGEMENT MODEL “Major hazard” safety management

systematic control and monitoring of the possible failure events (as modelled in the Technical Model) leading to Loss Of Containment of hazardous substances

Integrated management system model major hazard management is usually part of an

integrated SHE system Management system model structure

Control and Monitoring (feedback and learning) cycles 8 management subsystems: “Delivery systems”

delivering criteria and resources for control of major hazards

Primary business processes considered: Operations; Inspection, Testing and Maintenance;

Emergencies




OVERALL STRUCTURE OF MANAGEMENT MODEL

MAJOR HAZARD RISK CONTROL & MONITORING SYSTEM (RCMS)

DESIGN & MODIFICATIONS

POLICY, ORGANISATION AND STRUCTURE

DESIGN/MODIFICATION

INSPECTION/TEST, including maintenance concept MAINTENANCE

FEEDBACK & LEARNING LOOP(management

review)

FEEDBACK & LEARNING LOOPS

INSPECTION/TESTMAINTENANCE

OPERATIONS & EMERGENCY

ACTIVITIES & TASKS Outputs to Technical Model

OPERATIONS including emergency

8 Delivery Systems per primary business function

PRIMARY BUSINESS ACTIVITIES




DELIVERY SYSTEMS

Availability of personnel Commitment and motivation to carry out the work safely Internal communication and coordination of people Competence of personnel Resolution of conflicting pressures antagonistic to safety Plant Interface Plans and procedures Delivery of correct spares for repairs




DELIVERY SYSTEMS - Personnel

Competence: the knowledge, skills and abilities in the form of first-line and/or back-up personnel who have been selected and trained for the safe execution of the critical primary business functions and activities in the organisation. This system covers the selection and training function of the company, which delivers competent staff for

overall manpower planning.

Availability: allocating the necessary time (or numbers) of competent people to the safety-critical primary business tasks, which have to be carried out. This factor emphasises time-criticality, i.e. people available at the moment (or within the time frame) when the tasks should be carried out. This delivery system singles out the manpower planning aspects, which can include the planning of work of contractors during major shutdowns and the availability of staff for repair work on critical equipment outside normal work hours, including coverage for absence and holidays.

Commitment: the incentives and motivation, which personnel have to carry out their tasks and activities, with suitable care and alertness, and according to the appropriate safety criteria and procedures specified for the activities by the organisation. This delivery system is fairly closely related to the conflict resolution system, in that it deals with the incentives of individuals carrying out the primary business activities not to choose other criteria above safety, such as ease of working, time saving, social approval, etc. Organisational aspects of conflicts are dealt with there and, more personal aspects, such as violation of procedures here.




DELIVERY SYSTEMS - Hardware

Interface: The ergonomics of all aspects of the plant, which are used/operated by operations, inspection or maintenance. This covers design and layout of control rooms and manually operated equipment, location and design of inspection and test facilities, the maintenance-friendliness of equipment and the ergonomics of the tools used to maintain it. This delivery system covers both the appropriateness of the interface for the activity and the user-friendliness needed to carry out the activities.

Spares: These are the equipment and spares, which are installed during maintenance. This delivery system covers both the correctness of the spares for their use (like with like), and the availability of spares when and where needed to carry out the activities.




DELIVERY SYSTEMS - OrganizationalInternal communication and coordination: Internal communications are communications which occur implicitly, or explicitly within any primary business activity, i.e. within one task or activity linking to a parameter of the technical model, in order to ensure that the tasks are coordinated and carried out according to the relevant criteria. Conflict resolution: The mechanisms (such as supervision, monitoring, procedures, learning, group discussion) by which potential and actual conflicts between safety and other criteria (such as productivity) in the allocation and use of personnel, hardware and other resources are recognised, avoided or resolved if they occur. This delivery system is closely related to the one concerned with commitment, which covers the issues of violations within tasks at an individual level. The conflict resolution system covers the organisational mechanisms for resolving conflicts across tasks, between people at operational level and at management level.Procedures, Output goals and Plans: Rules and procedures are specific performance criteria which specify in detail, usually in written form, a formalised “normative” behaviour or method for carrying out an activity (checklist, task list, action steps, plan, instruction manual, fault-finding heuristic, form to be completed, etc.). Output goals are performance measures for an activity which specify what the result of the activity should be, but not how the results should be achieved. They are objectives, goals or outputs (e.g. accident/incident targets or trends, exposure of risk levels, ALARA, “safe”, numbers of activities carried out, etc.). It is also convenient to regard definitions and criteria for choosing one course of action over another as output criteria. Plans refer to explicit planning of activities in time, either how frequently tasks should be done, or when and by whom they will be done within a particular time period (month, shutdown period, etc.). They include the maintenance regime, maintenance scheduling (including shutdown planning) and testing and inspection activities, which need to link to the parameters of maintenance frequency, test interval and time for maintenance and repair.




MANAGEMENT TASKS

Deliver the appropriate control or resource to the appropriate primary business activity at the appropriate time

Learn and improve on that delivery process over time

These tasks are modelled as processes (boxes) linked by inputs, outputs and influences (arrows) in loops




Management tasksa) Overall management & Organization (1)b) Company Risk Control & Monitoring System (2)

(RCMS)c) Evaluate and Propose Chances in RCMS (12)d) Company System for managing and Monitoring

System (3)e) Control System (Use Delivery System to control

tasks) (4)f) Evaluate and propose changing delivery system (10)g) Record and analyze performance of delivery system

(9)h) Evaluate and propose changing use of the delivery

system (11)i) Correct on-line performance (8)




1Overall management

& organisation policy/system + adapt

to system climate 12Evaluate & propose changing overall management &/or RCS system/policy

INTEGRATED (PROBABLY) MANAGEMENT SYSTEM, COMMON TO ALL LOOPS

7Weighted delivery system

x parameters matrix

Modified value of task performance per base event per

parameter

Company Risk Control and Monitoring System

2

SYSTEM CLIMATE WITHIN WHICH THE SITE OPERATES

6Calibration models

for converting performance score to

failure data

Modified values of

base event parameters

Technical model

parameters from Base

Events table

INTERFACE & TECHNICAL MODEL

Analyse risks + design the control and monitoring

system + adapt to system climate

Control 4

system

Use delivery system to control tasks

9Record and analyse

performance, deviations, incidents

etc.

8Correct on line performance of

tasks

10Evaluate and

propose changing the way the delivery

system is used

11Evaluate & propose changing delivery

system

MANAGEMENTSUB-SYSTEMS

Monitoring system

3

3Company system for managing and

monitoring delivery system + adapt to

system climate

Performance (8 delivery systems x number of common mode management subsystems)

Quality of management evaluated by

AUDIT

MANAGEMENTMANAGEMENT

TASKS MODELTASKS MODEL




Data collected from equipment, tasks, and other sources

Output from one box becomes input for processing by the next

Influences from one box which can change the processing quality of the other

KEY

1Overall

management & organisation

policy/system + adapt

to system climate

12Evaluate & propose

changing overall management

&/or RCM system

INTEGRATED (PROBABLY) MANAGEMENT SYSTEM, COMMON TO ALL DELIVERY SYSTEMS

Company Risk Control Company Risk Control and Monitoring Systemand Monitoring System

Analyse risks + design the control and

monitoringsystem + adapt to

system climate

2

MANAGEMENT MODELMANAGEMENT MODEL

INFLUENCES from one Process can

change the quality of another. This

change takes time:TIME MODEL

An INPUT to a Process is the OUTPUT of a previous one. The quality on 0-10

scale: result of CALCULATION MODEL

application

OUTPUT from Process 12

becomes INPUT for Process 1

The current QUALITY of each MANAGEMENT

PROCESS is assessed in an AUDIT on a 0-10 scale

MANAGEMENT PROCESSES




Control SystemControl System44

Use delivery system to control

tasks

99Record and analyse

performance, deviations,

incidents etc.

88Corrections to on

line performance of tasks at the

workface

1010Evaluate and

propose changing the

way the delivery system is used

1111Evaluate &

propose changing delivery system

MANAGEMENTMANAGEMENTSUB-SYSTEMSSUB-SYSTEMSfor eachfor eachDELIVERY SYSTEMDELIVERY SYSTEM Monitoring Monitoring

systemsystem

3

33Company system for

managing and monitoring delivery system + adapt to

system climate

AUDIT the ‘BOXES’ Assessprocess

quality for each of the 8 DeliverySystems

7Weighted Delivery

System x Parameters Matrix

Quality on 0-10 scale of 8 Delivery System outputs

determined fromCALCULATION MODEL

Quality of “Procedures” is function of

•audited quality of 8 (AUDIT)•calculated quality of input from 4•weightings of their relative effects on output quality

Data collected from equipment, tasks, and other sources (not delivery specific)




1Overall management

& organisation policy/system + adapt

to system climate 12Evaluate & propose changing overall management &/or RCS system/policy

Control 4

system

Use delivery system to control tasks

9Record and analyse

performance, deviations, incidents

etc.

INTEGRATED (PROBABLY) MANAGEMENT SYSTEM, COMMON TO ALL LOOPS

8Correct on line performance of

tasks

10Evaluate and

propose changing the way the delivery

system is used

11Evaluate & propose changing delivery

system

MANAGEMENTSUB-SYSTEMS

Monitoring system

Company Risk Control and Monitoring System

Analyse risks + design the control and monitoring

system + adapt to system climate

2

3

3Company system for managing and

monitoring delivery system + adapt to

system climate

Performance (8 delivery systems x number of common mode management subsystems)

SYSTEM CLIMATE WITHIN WHICH THE SITE OPERATES

Technical model

parameters from Base

Events table

7Weighted delivery system

x parameters matrix

Modified value of task performance per base event per

parameter

INTERFACE & TECHNICAL MODEL

6Calibration models

for converting performance score to

failure data

Modified values of

base event parameters

MANAGEMENTMANAGEMENT

TASKS MODELTASKS MODEL




Audit ObjectivesAudit Objectives

Integrated assessmentIntegrated assessmentMajor hazards as focus for Major hazards as focus for

articulation of management systemarticulation of management systemModification at technical parameterModification at technical parameterSensitivity analysis for significantSensitivity analysis for significant

corrosion factors in management corrosion factors in management systemsystem

Use a microcosm to study the wholeUse a microcosm to study the wholemajor hazard management systemmajor hazard management system




Audit Procedure

Preparation:Preparation: Construct technical model: completeness of scenarios Group basic & initiating events into clusters with same

management Link initiating events to management system: expert judgement Map company SMS onto I RISK model: who to interview / tailoring

Conduct: Auditor expertise: process + management + benchmarking of

industry Focus on scenarios Prompt lists and recording forms Verification across interviews and with checks in practice




Audit EvaluationAudit Evaluation

Assessment per box:Assessment per box:

Scale of 1-10 compared to industry averageScale of 1-10 compared to industry average: : anchoring, baselineanchoring, baseline

Interrater reliability:Interrater reliability: refinery, av.refinery, av. 0.74, range 0.1-0.80.74, range 0.1-0.8 ammonia, av 0.73,range 0.49-0.96ammonia, av 0.73,range 0.49-0.96

Discussion or blind re-ratingDiscussion or blind re-rating: : av. 0.85av. 0.85

Relative weighting of delivery systems Relative weighting of delivery systems per task/parameter per task/parameter




MODELING OF THE SAFETY MANAGEMENT SYSTEM

yi =fi(xi,y1,…,yj,…yI)

yi output of box i

fi function of box i

xi state of box i

yj (j i) input of box i

yi =kiixi+(1-kii)Σcijyj y=Kx+(I-K)Cy

y=[I-(I-K)C]-1Kx




Management –Technical Interface Model

11 12 13

1415 16

ManagementProcesses forcommon mode

A

BaseEvents:

EventParameters:




8

mj=Σy8iwij

i =1

mj modification factor of the jth technical parameter

y8i output of the ith delivery system (box 8)

wij weighting factor assessing the relative importance of the ith management delivery system on the influence of the jth technical parameter

j index running over the basic events of the kth group

MODIFICATION OF THE FREQUENCY OF LOC ACCORDING TO THE SMS




1 2 3 4 5 6 7 8

Qo1 0.06 0.15 0.07 0.16 0.18 0.2 0.18 0

Qo2 0.05 0.14 0.05 0.21 0.21 0.2 0.14 0

QM1 0.08 0.19 0.06 0.14 0.14 0.08 0.17 0.14

QM2 0.05 0.13 0.05 0.22 0.18 0.18 0.15 0.04

fi 0.1 0.2 0.1 0.1 0.1 0 0.4 0

λ 0.08 0.12 0.12 0.08 0.08 0.08 0.16 0.28

Τ 0.05 0.24 0.14 0 0.28 0.05 0.19 0.05

fm 0.05 0.21 0.16 0 0.32 0.05 0.16 0.05

TR 0.12 0.07 0.21 0.09 0.1 0.19 0.1 0.2

TM 0.12 0.08 0.21 0.08 0.12 0.17 0.08 0.14

WEIGHTING FACTORS




DYNAMIC MODELING

=Ax+By (1)

A=[aij] influence of state of box j on rate of change of state of box i

B=[bij] influence of output of box j on rate of change of state of box i

y=[I-(I-K)C]-1Kx (2)

(1),(2) =[A+B[I-(I-K)C] -1K]x

x

x




DYNAMIC MODELING

i=[Σaijxj+Σbijyj]fi(xi)

fi(xi): state specific resistance

=F(x)[A+B[I-(I-K)C] -1K]xx

x




CASE STUDY: AMMONIA STORAGE TANK




EVENT TREE

LOSS OF REFRIGERATION

(STORAGE)FLARE

SAFETY VALVES

(1)

(2)

(3) 8 EVENT TREES 17 FAULT TREES128 BASIC EVENTS




GENERIC DELIVERY SYSTEMS QUALITY

1. OVERALL MANAGEMENT 5.0

2. COMPANY RCMS 6.0

3. EVALUATE RCMS 2.13

AVAILABILITY

4. COMPANY SYSTEM 5.33

5. CONTROL SYSTEM 4.6

6. CORRECT ON LINE PERFORMANCE 4.75

7. RECORD &ANALYSE ON LINE PERFORMANCE

2.75

8. EVALUATE AND PROPOSE CHANGING THE WAY IT IS USED

3.67

9. EVALUATE AND PROPOSE CHANGING 3.33




TECHNICAL PARAMETER

MODIFICATION FACTOR

Qo1 3.6

Qo2 3.76

QM1 3.93

QM2 3.86

fi 3.66

λ 3.97

Τ 3.46

fm 3.97

TR 3.65

TM 3.70

MODIFICATION FACTORS




Lower and upper values of technical parameters

EQUIPMENT PARAMETER Lower Upper

1 Safety valves, remote control valves Tr, Tm (hr) 24 8760

2 All equipment T Plant data x 0.9 Plant data x 1003 Safety valves, remote control valves λ 1.71x10-6 3.15 x10-5

4 All equipment Qm1 1.00 x10-4 0.5

5 All equipment Qm2 5.00x10-2 1

6 Safety valves fail in open position λ 8.50 x10-7 3.40 x10-5

7 Manual valves λ 2.74 x10-7 5.04 x10-6

8 Manual valves Tr, Tm, T (hr) Plant data x 0.9 Plant data x 100

9 Flow instruments λ 8.30 x10-7 5.59 x10-6

10 Flow instruments Tr, Tm (hr) 24 336

11 Instruments where equipment has to be taken apart for repair

Tr, Tm (hr) 24 8760

12 Level instrument λ 2.50 x10-6 1.10 x10-5

13 Pressure instrument λ 2.50 x10-7 2.94 x10-614 Temperature instrument λ 3.00 x10-8 2.97 x10-5

15 Process pump λ 4.50 x10-5 2.28 x10-4

16 Process pump Tr, Tm (hr) 24 8760

17 Human Error Qo11.00 x10-4 5.00 x10-1

18 Human Error Qo25.00 x10-2 1.00




CURRENT, BEST AND WORST CASE FREQUENCIES

OVERPRESSURE STORAGE

OVERPRESSURE LOADING

UNDERPRESSURE

PIPEBREAK

CURRENT STATE

1.1 10-5 2.2 10-6 1.2 10-6 1.4 10-4

WORST CASE

6.1 10-3 8.7 10-2 5.5 10-4 5.0 10-2

BEST CASE 2.9 10-10 4.3 10-10 1.9 10-10 5.5 10-6




IMPORTANCE ANALYSIS

fLOC=g(b)

b=u(q)

q=w(q*)

q*=My8=MHx

IMPORTANCE MEASURE :

fLOC : frequency of Loss of Containment

b : vector of basic events

q : vector of technical parameters

x : vector of state of manegerial tasks

ix

fLOC




GENERIC DELIVERY SYSTEMS QUALITY IMPORTANCE

1. OVERALL MANAGEMENT 5.0 0

2. COMPANY RCMS 6.0 0

3. EVALUATE RCMS 2.13 0

AVAILABILITY

4. COMPANY SYSTEM 5.33 0

5. CONTROL SYSTEM 4.6 5.29 x 10-7

6. CORRECT ON LINE PERFORMANCE

4.75 13.21 x 10-7

7. RECORD &ANALYSE ON LINE PERFORMANCE

2.75 2.11x10-7




MOST IMPORTANT TASKS QUALITY IMPORTANCE

48. CORRECT ON LINE PERFORMAN- CE OF SPARES

5.0 29.34 x10-7

42. CORRECT ON LINE PERFORMAN-CE OF PLANS AND PROCEDURES

3.2 27.80 x10-7

12. CORRECT ON LINE PERFORMAN-CE OF COMMITMENT

3.00 24.36 x10-7

30. CORRECT ON LINE PERFORMAN-CE OF CONFLICT RESOLUTION

4.0 22.70 x10-7




QUALITY OF DELIVERY SYSTEMS VERSUS TIME

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0 5 10 15 20

TIME

RE

LA

TIV

E Q

UA

LIT

Y

AVAILABILITY

COMMITMENT

COMMUNICATION

COMPETENCE

CONFLICTRESOLUTIONINTERFACE

PROCEDURES

SPARES & TOOLS




PERFORMANCE SCORE VERSUS TIME

0

0.1

0.2

0.3

0.4

0.5

0.6

0 5 10 15 20

TIME

RE

LA

TIV

E Q

UA

LIT

Y

Qo1

λ

T

Tr




FREQUENCY OF FAILURE OF LOC VERSUS TIME

1.E-07

1.E-06

1.E-05

1.E-04

1.E-03

0 5 10 15 20

TIME

FR

EQ

UE

NC

Y (

/hr)

TankOverpressurestorageTankOverpressureloadingTankunderpressure

pipebreak




T6655

T6656

T6654

LPG

LPG

MEA

MEA

NAOH

NAOH

H2O

H2O

CASE STUDY: LPG SCRUBBER




DIRECT CAUSES OF LOC

TOWER FAILURE FROM OVERPRESSURE CAUSED BY

HEAT FLUX FROM EXTERNAL SOURCE

TOWER FAILURE FROM OVERPRESSURE, OWING TO

OVERFILLING

TOWER FAILURE OWING TO AGING

TOWER FAILURE OWING TO FREEZING

EXTRA LOADS OWING TO A ROAD ACCIDENT




INITIATING EVENTS

EXTERNAL FIRE

HIGH INLET OF MEA OWING TO VALVE FAILURE

NO OUTLET OF MEA

HIGH INLET OF CAUSTIC

NO OUTLET OF CAUSTIC

HIGH INLET OF WATER OWING TO VALVE FAILURE

NO OUTLET OF WATER

HIGH INLET OF LPG

NO OUTLET OF LPG

OPERATING CONDITIONS OFF SPECIFICATIONS




SAFETY SYSTEMS

PRESSURE DETECTION SYSTEM

FIRE SUPPRESSION SYSTEM

PRESSURE SAFETY VALVES

LOW LEVEL PROTECTION SYSTEM IN TOWERS T6654, T6655, T6656

HIGH LEVEL PROTECTION SYSTEM IN TOWER T6654, T6655, T6656

TOWER INTEGRITY




EVENT TREE

HIGH INLET OF MEA

OUTLET FULLY OPEN

PSV

(1)

(2)

(3)10 EVENT TREES 9 FAULT TREES

41 BASIC EVENTS




GENERIC DELIVERY SYSTEMSQUALITY

1. OVERALL MANAGEMENT 9.3

2. COMPANY RCMS 9.0

3. EVALUATE RCMS 7.0

AVAILABILITY4. COMPANY SYSTEM 8.9

5. CONTROL SYSTEM 9.8

6. CORRECT ON LINE PERFORMANCE 9.9

7. RECORD &ANALYSE ON LINEPERFORMANCE

8

8. EVALUATE AND PROPOSE CHANGINGTHE WAY IT IS USED

8.9

9. EVALUATE AND PROPOSE CHANGING 7




TECHNICALPARAMETER

MODIFICATION FACTOR

Qo1 9.1

Qo2 9.0

QM1 9.3

QM2 9.0

fi 9.5

λ 9.3

Τ 9.4

fm 9.3

TR 9.1

TM 9.2

MODIFICATION FACTORS




FAILURE FREQUENCY CATASTROPHIC FAILURE OF TOWER T6654

PLANT AS ASSESSED 4.7 x 10-10/hr

BEST POSSIBLE CASE 1.1 x 10-10/hr

WORST POSSIBLE CASE 1.2 x 10-4/hr




EXTREME PHENOMENA FOLLOWING PLANT DAMAGE STATES

CATASTROPHIC FAILURE OF TOWER T6654 (2700 Kg LPG)

1. BLEVE

2. FLASH FIRE

3. EXPLOSION




RISK INTEGRATION

1.0E-08

1.0E-07

1.0E-06

1.0E-05

1.0E-04

1.0E-03

1.0E-02

1.0E-01

0 0.5 1 1.5 2 2.5 3 3.5

AREA (Km2) WHERE INDIVIDUAL RISK IS ABOVE CERTAIN LEVELS (10-1 - 10-8 /yr)

Specificcase

Worst case

Best case




FREQUENCY OF FAILURE VERSUS TIME

0.00E+00

5.00E-10

1.00E-09

1.50E-09

2.00E-09

2.50E-09

0 20 40 60 80 100 120 140 160 180 200

"TOWER T6655" "TOWER T6654" "TOWER T6656"




GENERIC DELIVERY SYSTEMSQUALITY IMPORTANCE

1. OVERALL MANAGEMENT 9.3 0

2. COMPANY RCMS 9.0 0

3. EVALUATE RCMS 7.0 0

AVAILABILITY4. COMPANY SYSTEM 8.9 0

5. CONTROL SYSTEM 9.8 1.8 x 10-11

6. CORRECT ON LINEPERFORMANCE

9.9 4.4 x 10-11

7. RECORD &ANALYSE ON LINEPERFORMANCE

8 7.1x10-12

8. EVALUATE AND PROPOSECHANGING THE WAY IT IS USED

8.9 4.7x10-12

9. EVALUATE AND PROPOSECHANGING

7 0




MOST IMPORTANT TASKS

QUALITY IMPORTANCE

48. CORRECT ON LINE PERFORMAN-CE OF SPARES

9.6 9.6x10-10

12. CORRECT ON LINE PERFORMAN-CE OF COMMITMENT

9.8 1.4x10-10

30. CORRECT ON LINE PERFORMAN-CE OF CONFLICT RESOLUTION

9.1 1.4x10-10

42. CORRECT ON LINE PERFORMAN-CE OF PLANS AND PROCEDURES

9.8 1.3x10-10

Documents

NATIONAL CENTER FOR SCIENTIFIC RESEARCH “DEMOKRITOS” LAB. OF SYSTEMS RELIABILITY AND INDUSTRIAL SAFETY INSTITUTE OF NUCLEAR TECH. RADIATION PROTECTION