INTERNATIONAL WORKSHOP ON MARINE OIL POLLUTION CONTROL - ATHENS, GREECE 09, June 2006 POP&C –...

INTERNATIONAL WORKSHOP ON MARINE OIL POLLUTION CONTROL - ATHENS, GREECE

09, June 2006

POP&C – POLLUTION PREVENTION & CONTROLRisk/Pollution Reduction and Expert Group Judgment

in the Maritime Industry

Risk/Pollution Reduction and Expert Group JudgmentRisk/Pollution Reduction and Expert Group Judgmentin the Maritime Industryin the Maritime Industry

Dr. N.P. Ventikos, P.G. Anaxagorou, NTUADr. N.P. Ventikos, P.G. Anaxagorou, NTUA


09, June 2006



• TargetsTargets

• Basis of Approach – Basis of Approach – Implemented MethodologyImplemented Methodology

• Consequence Analysis – ResultsConsequence Analysis – Results

• Expert Judgment Assessment – Examples Expert Judgment Assessment – Examples

• Proposal of Case Studies (Consequence / Risk)Proposal of Case Studies (Consequence / Risk)

• Presentation of The Pollution Control Options Presentation of The Pollution Control Options

OVERVIEW


09, June 2006



• Based on Specific ET StructuresBased on Specific ET Structures

• Analysis & Exploitation of Answers/Judgment from Group of Analysis & Exploitation of Answers/Judgment from Group of Experts Regarding the Consequence/Risk Potential of each of the Experts Regarding the Consequence/Risk Potential of each of the Provided Casualty Scenarios for TankersProvided Casualty Scenarios for Tankers

• Identification of Risk/Pollution Control Options (through Case Identification of Risk/Pollution Control Options (through Case Studies)Studies)

TARGETS


09, June 2006



• Post Accident AssessmentPost Accident Assessment

• Questionnaires and ET Structure (per Type of Casualty) was Provided to Questionnaires and ET Structure (per Type of Casualty) was Provided to the Expert Groupthe Expert Group

• Expert Group JudgmentExpert Group Judgment

• Assessment of Expert Group Judgment (not Possible through the Assessment of Expert Group Judgment (not Possible through the Concordance Coefficient ‘W’, Annex of MSC 78/19/2)Concordance Coefficient ‘W’, Annex of MSC 78/19/2)

• Classification and Rule-based Knowledge TheoryClassification and Rule-based Knowledge Theory

• Consequence-based Analysis and Risk-based Analysis Consequence-based Analysis and Risk-based Analysis Rules & Rules & Decision TreesDecision Trees

• Pollution Control Options (through the Proposal and Survey of Case Pollution Control Options (through the Proposal and Survey of Case Studies)Studies)

KEY STEPS OF IMPLEMENTED METHODOLOGY


09, June 2006



ACCIDENT

ET Structure

ET Scenarios

Answers from Expert Group

METHODOLOGY INPUTSEvent Gates

Scenarios/Endings

Experts’ Scoring 1 Frequency & 3 Severity Slots


09, June 2006



PROVIDED SCALES FOR SCORING/VOTING


09, June 2006



ET ScenariosAnswers from ExpertsProcessing of Answers for ConsequenceMapping (Distribution) of VotesAssessment of Expert Judgment & ConsensusRules & Decision TreesCritical Events & Simplified ScenariosConsequence Analysis

METHODOLOGY STEPS FOR CONSEQUENCE ANALYSIS

The scope is to identify/simulate what the experts perceived as important in terms of events for giving their consequence/probability ranking and differentiate the practical value of one index to another this way it can be identified where the experts focused on the structure of the ET and how they actually proceeded in the scoring of the numerous provided scenarios per type of casualty


09, June 2006



MAPPING OF VOTES – CONSEQUENCE

Contact

23%

65%

7%5%

4 3 2 1

Grounding

63%

25%

10% 2%

4 3 2 1

Collision

72%

14%

9% 5%

4 3 2 1

Fire

79%

0%13%

8%

4 3 2 1

Str-failure

58%

13%6%

23%

4 3 2 1

Explosion

84%

4%4% 8%

4 3 2 1


09, June 2006



MAPPING OF VOTES

distribution of risk value per 60 scenarios

0

5

10

15

20

25

30

35

40

45

50

6+7 high risk 5 4 3 2

# o

f sc

enar

ios

contact collision grounding struct-failure fire explosion

distribution of consequence value per 60 scenarios

0

10

20

30

40

50

60

4+3 high consequence 2 1

# o

f sc

enar

ios

contact collision grounding struct-failure fire explosion

GROUNDING : DETAILED RISK ANALYSIS OF MODE 6

0

1

2

3

4

0 1 2 3 4 5 6 7

FREQUENCY

CO

NS

EQ

UE

NC

E


09, June 2006



collision-consequence-experts' detaled voting

51

34 3626

34

51

18

51

32

612

1813

13

15

3 55

63

14

36

2

16

3 7 3 211

2 3

1 2 3 4 5 6 7 8 9

1

2

3

4

collision-risk-experts' detailed voting

1

34

1 17

6

11 5 7 6

17

2

26

19 18 18

29

14

39

7

35

29

9

29

33

2

139

17

2

16

2

19

4 3 4 6 4

1 2 3 4 5 6 7 8 9

3

4

5

6

7

8

EXPERT JUGDMENT – DETAILED


09, June 2006



GROUNDING : DETAILED DISTRIBUTION OF EXPERTS' VOTE (CONSEQUENCE MODE 4)

0%

25%

50%

75%

100%

1 2 3 4 5 6 7 9 10

11

12

13

14

15

18

19

21

22

24

25

27

29

32

34

35

40

43

44

45

46

47

48

49

51

54

57

# OF SCENARIOS

% O

F V

OT

E

4 3 2 1

High Consequence Scenarios Present a Significant Experts’ Consensus. In Particular 67% of these Scenarios Received High Consequence Ranking and Only 1% Received Scores Ranging from Low to High Consequence

ASSESSMENT OF EXPERT JUDGMENT & CONSENSUS


09, June 2006



GROUNDING: EXPERTS' CONSENSUS ON CONSEQUENCE MODE 4

0

1

2

3

4

5

6

7

8

9

1 2 3 4 5 6 7 9 10

11

12

13

14

15

18

19

21

22

24

25

27

29

32

34

35

40

43

44

45

46

47

48

49

51

54

57

# OF SCENARIOS

# O

F E

XP

ER

TS

-3

-2

-1

0

1

2

EX

PE

RT

S' D

EV

IAT

ION

MODE 4

Experts' Consensus

Experts' Deviation

Only 17% of High Consequence Scenarios Received the Minimum Consensus (50%) of the Involved Experts

ASSESSMENT OF EXPERT JUDGMENT & CONSENSUS


09, June 2006



Rule 0/1: Breach in hull = no Hard Aground = no -> class 1 [0.833]Rule 0/2: Breach in hull = no Hard Aground = yes -> class 2 [0.833]Rule 0/3: Breach in hull = yes Breach in inner hull = no Hard Aground = no Ship breaks into piece = no -> class 2 [0.600]Rule 0/4: Breach in hull = yes Breach in inner hull = no Hard Aground = yes Ship breaks into piece = no -> class 3 [0.875]Rule 0/5: Breach in inner hull = yes Hard Aground = no Ship sinks without breaking into pieces = no Ship breaks into piece = no -> class 3 [0.750]Rule 0/6: Breach in hull = yes Breach in inner hull = na Hard Aground = no Ship sinks without breaking into pieces = no Ship breaks into piece = no -> class 3 [0.714]

Rules:

Rule 0/7: Breach in hull = yes Breach in inner hull = na Hard Aground = yes -> class 4 [0.909]Rule 0/8: Ship breaks into piece = yes -> class 4 [0.909]Rule 0/9: Breach in inner hull = yes Hard Aground = yes -> class 4 [0.889]Rule 0/10: Ship sinks without breaking into pieces = yes -> class 4 [0.833]

Decision tree:

Breach in hull = no::...Hard Aground = yes: 2 (4): Hard Aground = no: 1 (4)Breach in hull = yes::...Ship breaks into piece = yes: 4 (20/1) Ship breaks into piece = no: :...Breach in inner hull = no: :...Hard Aground = yes: 3 (6) : Hard Aground = no: 2 (8/3) Breach in inner hull = yes: :...Ship sinks without breaking into pieces = yes: 4 (6) : Ship sinks without breaking into pieces = no: : :...Hard Aground = yes: 4 (5) : Hard Aground = no: 3 (10/2) Breach in inner hull = na: :...Hard Aground = yes: 4 (7) Hard Aground = no: :...Ship sinks without breaking into pieces = yes: 4 (2) Ship sinks without breaking into pieces = no: 3 (5/1)

GROUNDING : RULES & DECISION TREES


09, June 2006



According to the Experts Scoring and the Results From the Methodology the High Consequence Scenarios Incorporate One of the Following Simplified Scenarios Given a Grounding:

• Single Hull Tanker that Suffered a Breach in Hull and Run Hard Aground or • Double Hull Tanker that Suffered a Breach in Inner Hull and Run Hard Agroundor• Single or Double Hull Tankers that Break into Piecesor • Single or Double Hull Tankers that Sink Without Breaking into Pieces

GROUNDING – CONSEQUENCE: SIMPLIFIED RESULTS


09, June 2006



THE PROPOSED CASE STUDIES

1 BRAER BRAER (SHETLANT UK, 1993), SEA EMPRESSSEA EMPRESS (UK, 1996)

Grounding (2)

2 ATLANTIC EMPRESSATLANTIC EMPRESS (TOBAGO, 1979) Collision

3 ERIKA (ERIKA (UK, 1999), PRESTIGE PRESTIGE (SPAIN, 2002) Non Acc. Str. Failure (2)

4 MEGA BORGMEGA BORG (GALVESTONE, 1990) Fire

5 ABT SUMMERABT SUMMER (ANGOLA, 1991) Explosion

6 CATJACATJA (FRANCE, LE HAVRE PORT, 1995) Contact


09, June 2006



collision-consequence-experts' detaled voting

51

34 3626

34

51

18

51

32

612

1813

13

15

3 55

63

14

36

2

16

3 7 3 211

2 3

1 2 3 4 5 6 7 8 9

1

2

3

4

fire-consequence-experts' detaled voting

2018 18

20

8

20 19

2 2

5

23 3

9

3

2 3 3 2 2 2 2

1 2 3 4 5 6 7 8 9

1

2

3

4

structural failure-consequence-experts' detaled voting

18 18 18

7 8 7

13

25

2 4

1 2 3 4 5 6 7 8 9

1

2

3

4

Experts’ Voting Distribution for CollisionExperts’ Voting Distribution for CollisionThree experts gave identical distribution (#1, #6, #8) with a great concentration around the high consequence scenarios. One of them (#7) has a more ‘balanced’ opinion

Experts’ Voting Distribution for FireExperts’ Voting Distribution for FireOne of the experts (#7) has completely different scoring distribution comparing to the others. Identical distributions were given again by #1, #6 and #8 and by #3 and #5 accordingly

Experts’ Voting Distribution for Non Accidental Experts’ Voting Distribution for Non Accidental Structural FailureStructural FailureIn the case of non accidental structural failure only 3 out of 9 experts assessed the scenarios. Their scorings provide similar distributions for high consequence scenarios

COMMENTS ON EXPERT JUDGMENT


09, June 2006



COLLISION: DISTRIBUTION OF EXPERTS' VOTE (CONSEQUENCE MODE 4)

0%

25%

50%

75%

100%

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 19 20 22 24 25 29 30 33 34 36 39 40 42 45 46 47 48 49 50 52 54

# OF SCENARIOS

% O

F V

OT

E4 3 2 1

STRUCTURAL FAILURE: DETAILED DISTRIBUTION OF EXPERTS' VOTE

(CONSEQUENCE MODE 4)

0%

25%

50%

75%

100%

1 2 5 6 8 9

11

12

14

17

19

20

22

24

25

27

28

30

# OF SCENARIOS

% O

F V

OT

E

4 3 2 1

Experts’ Detailed Voting Experts’ Detailed Voting Distribution for High Distribution for High Consequence Scenarios in the Consequence Scenarios in the Case of CollisionCase of CollisionThe high consequence scenarios present a significant expert consensus. In particular 71% of these scenarios received high consequence ranking

Experts’ Detailed Voting Distribution for High Experts’ Detailed Voting Distribution for High Consequence Scenarios in the Case of Structural Consequence Scenarios in the Case of Structural FailureFailureIn this case the high consequence scenarios present a total (100%) expert consensus

COMMENTS ON EXPERT JUDGMENT


09, June 2006



6 MAIN PCO CATEGORIES – 19 NEW PCOs6 MAIN PCO CATEGORIES – 19 NEW PCOs

• Procedures for Emergency Response (Place Of Refuge) – 5 PCOsProcedures for Emergency Response (Place Of Refuge) – 5 PCOs• Tug Assistance – 3 PCOsTug Assistance – 3 PCOs• Tanker Design and Associated Regulations – 1 PCOTanker Design and Associated Regulations – 1 PCO• Systems Onboard – 5 PCOsSystems Onboard – 5 PCOs• Systems for Pollution Control and Mitigation – 3 PCOsSystems for Pollution Control and Mitigation – 3 PCOs• Human Factor – Training – 2 PCOs Human Factor – Training – 2 PCOs

THE POLLUTION CONTROL OPTIONS


09, June 2006



PCO 18:PCO 18: Develop emergency preparedness through suitable training and awareness as part of the Safety Management System of ISM (all types of events)PCO 19:PCO 19: Training sessions should be dedicated to emergency procedures and in particular, there should be focus on firefighting methods and response methods in case of explosions (all types of events)

PCO 15:PCO 15: Consider the fitting of system for pollution control and mitigation. In particular, systems which facilitate the transshipment of oil for sunk and upturned ships. Assess the effectiveness of fitting systems such as Fast Oil Recovery systems for different situations (all types of events, ONBOARD)PCO 16:PCO 16: Availability of systems for receiving significant quantities of oil without the need of a lightering tanker in critical location or directly on tankers (all types of events, ONBOARD)PCO 17:PCO 17: Availability of systems onboard the tankers for the containment of oil spilled such as booms or more innovative systems, such as HARDOIL (all types of events, ONBOARD)

HUMAN FACTOR – TRAINING

SYSTEMS FOR POLLUTION CONTROL AND MITIGATION


09, June 2006



• Experts Population (# of Experts that Assessed the Scenarios)Experts Population (# of Experts that Assessed the Scenarios)

• Experts Mixture (Different Professions & Experience)Experts Mixture (Different Professions & Experience)

• Forms/Questionnaires Provided – Time DedicatedForms/Questionnaires Provided – Time Dedicated

• Cooperation Between ExpertsCooperation Between Experts

• The Focus of the Experts (Which are the Key Events that Attract The Focus of the Experts (Which are the Key Events that Attract

Their Attention?)Their Attention?)

• Measurable and Quantifiable Scales for ScoringMeasurable and Quantifiable Scales for Scoring

• RankingRanking

• Difficulty in Assessing the Outcome from the Expert Group JudgmentDifficulty in Assessing the Outcome from the Expert Group Judgment

CONCLUSIONS FROM EXPERT VOTING


09, June 2006



Difficult Puzzle!!Difficult Puzzle!!

EXPERT GROUP JUDGMENT IN THE MARITIME INDUSTRY

INTERNATIONAL WORKSHOP ON MARINE OIL POLLUTION CONTROL - ATHENS, GREECE 09, June 2006 POP&C –...

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