Ships in Service Training Material Risk Assessment Analysis Tools 2009.
-
Upload
melinda-dean -
Category
Documents
-
view
219 -
download
1
Transcript of Ships in Service Training Material Risk Assessment Analysis Tools 2009.
Ships in Service Training Material
Risk Assessment Analysis Tools
2009
What is the potential event
What can bethe consequences
What can bethe causes
Risk Assessment
Ships in Service Training Material A-M CHAUVEL
What are the actual control measures
What can be done
What is the risk
General Method
- Pareto- Preliminary hazard- Job safety- Quantitative risk- Qualitative risk- What if- Fault tree- Event tree- Bow tie- Failure mode and effects- Hazard and operational
Ships in Service Training Material A-M CHAUVEL
Risk Assessment Tools Analysis
( PAR )( PHA )( JSA )( QRA )( qRA )( WIF/SWIF )( FTA )( ETA )( BTA ) ( FMEA )( HAZOP )
Scope of Application of the Tools
Pareto
ChecklistPreliminary hazard (PHA)
What if (WIF or SWIF )
Failure mode and effects (FMEA)
Hazard and operability (HAZOP)
Fault tree (FTA)
Event tree (ETA)
Bow tie Diagram (BTA)
Tools
X
X
X
X
X
X
X
X
X
X
X
X
x
Hazardidentification
Risk screening
Risk Assessment
Ships in Service Training Material A-M CHAUVEL
Risk Assessment Toolsused in
combination during Workshop
Ships in Service Training Material A-M CHAUVEL
1 - Pareto
2 - Checklist
3 - Preliminary hazard (PHA)
4 - What if (WIF or SWIF)
5 - Failure mode and effects (FMEA)
6 - Hazard and operability (HAZOP)
7 - Fault tree (FTA)
8 - Event tree (ETA)
9 - Bow tie Diagram (BTA)
X
X
X
X
X
X
3, 10,
8, 7, 6,
3, 4, 10, 3, 8,
10, 3,
7, 5,
2,
2, 8, 5
7, 2,
7 & 8
Risk assessment toolsnumber
AloneWith other
tools(Number)
Ships in Service Training Material A-M CHAUVEL
10 - Change analysis (CA) X 1, 3, 4, 8,
Risk Assessment Tools Usage
Ships in Service Training Material A-M CHAUVEL
Just because we know how to do a jobdoesn't mean that we do it safely.
Risk Analysis Tools
Example:An airplane is a safety critical system.
As one level of analysis, a pilot must complete a pre-flight checklist before flight to ensure
that the plane is working properly.
Ships in Service Training Material A-M CHAUVEL
Checklists
Despite their simplicity,checklists are a form of
Quality & Safety Analysis.
This checklist is a simple form of Safety Analysis.
They are generally useful where a problem is well understood, and examination rather than system analysis is the goal.
Ships in Service Training Material A-M CHAUVEL
Checklists
1.0 Define theActivity orthe System
6.0 Subdivide the elements of the
activity or system( If necessary )
3.0 Subdivide theSystem or Activity
for analysis
4.0 Gather orcreate relevant
checklists
5.0 Respond to theChecklistquestions
2.0 Define thepotential hazards
7.0 Use the results in decision making
Checklists
Ships in Service Training Material A-M CHAUVEL
Process
Checklists
Ships in Service Training Material A-M CHAUVEL
- Possibly miss some potential problems.
- Traditionally provides only qualitative information.
Activity Level 1 Level 2 Level 3 Level 4
C1- Chemical, biological and radiation hazard control referenceInformationavailability andknowledge.
No knowledge or use of referencedata.
Data available and used by supervisorwhen needed.
Additional standards have been requested when necessary. Employees and supervisors able todemonstrate an understandingof the material.
Data posted and followed where needed. Additional standards havebeen promulgated, reviewed with employees involved and posted.
C2- Flammable andexplosive materials control.
Storage of materialsdo not meet fireregulations.
Some storage facilities meet minimum fire regulations.
Storage facilities meetminimum fire regulations.
Handling practices alsomeet minimum regulatory requirements.
.
In addition to “Good”,Storage facilities exceed the minimum fire regulations. A strong policy is in evidence relative to the control of the handling, storage and use offlammable/explosive materials.
NoYes
NoYes
NoYes
NoYes
NoYes
NoYes
NoYes
NoYes
Limitation
Ships in Service Training Material A-M CHAUVEL
Preliminary Hazard Analysis
Risk Analysis Tools
Ships in Service Training Material A-M CHAUVEL
Preliminary HazardProcess
RISKASSESSMENT
1.0 Define theActivity orthe System
3.0 Conductreview
2.0 Precise thecategories of
accident and theaccident severity
4.0 Use the resultsin decision making
Ships in Service Training Material A-M CHAUVEL
Brief description Title ( Portion of the System/Sub-system/ Operational Phase covered by this analysis):
Probability Interval:5 years
System Number:
Date:
Analysis: I: InitialR: Revision A: Addition
Hazard Description
RiskBefore
Haz
ard
targ
et
Ris
k
Co
de
Pro
bab
ilit
y
Sev
eri
ty
Prepared by/date: Hazard target : P- Personnel, E- Equipment
T- Down time, R- Product, V- Environment
Preliminary Hazard Worksheet
Hazard(PotentialAccident)
CauseMajor
effects
Severity(AccidentCategory)
Corrective or PreventiveMeasures suggested
Fuel oil spill
Ship motionaway fromthe transferterminalduringbunkering
Release offuel oil intothe waterway, resulting in significantenvironmentalimpact
2
Consider installing mooring tensionmeters with alarms to indicate ship motion during bunkering
LNG fireor explosion
Loss ofventilationin thecompressorroom
Potential forexplosion & large fire withfatalities
1
Consider providing an alarm thatindicates when the ventilation fanin the compressor roomshuts down
Area :Drawing number :
Meeting date :Team members :
Ships in Service Training Material A-M CHAUVEL
Preliminary Hazard ReportExample
Ships in Service Training Material A-M CHAUVEL
Brief description Title ( Portion of the System/Sub-system/ Operational Phase covered by this analysis):
Probability Interval:
System Number:
Date:
Analysis: I: InitialR: Revision A: Addition
Hazard Description
RiskAfter
Description of Control measuresRiskBefore
Identify countermeasures by appropriate code letter (s):D: Design alterationS: Safety device
E: Engineering safety featureW: Warning device
P: Procedures / training Ris
k
Co
de
Pro
bab
ilit
y
Sev
eri
ty
Haz
ard
targ
et
Ris
k
Co
de
Pro
bab
ilit
y
Sev
eri
ty
Prepared by/date: Approved by/date:
Preliminary Hazard Analysis
Hazard target : P- Personnel, E- Equipment
T- Down time, R- Product, V- Environment
Ships in Service Training Material A-M CHAUVEL
Job Safety Analysis
Risk Analysis Tools
Japanese Style for Abandon Ship
Day one of the JHAJapanese Hemorrhoid Association's annual cruise...”
Risk Analysis JSA and not JHA
Ships in Service Training Material A-M CHAUVEL
Ships in Service Training Material A-M CHAUVEL
Job Safety
RISKASSESSMENT
Process
1- Select a job for analysis
4- Developcountermeasures
2- Break job down into basic
work elements3- Scrutinizeeach element
- Workers must adopt harmful postures in order to handle loads.
- Workers are expected to lift loads which are too heavy. - Objects are not designed for ease of handling. - Workplaces are poorly designed (including work stations). - Work systems are poorly designed.
How Handling Injuries Occur ?
Ships in Service Training Material A-M CHAUVEL
These injuries often occur because :
Ships in Service Training Material A-M CHAUVEL
Job Safety Worksheet
Platform: I.D: Location:
Field Superintendent: Analysis made by:
Task: Loading and unloading truck
Personnel Protective Equipment required and/or recommended:
Sequence of basic job steps: Potential accidents or hazards:
1
X
Recommendation to eliminateor reduce potential hazard:
Ships in Service Training Material A-M CHAUVEL
Job Safety Worksheet
Deck Officer: Location:
Security Officer: Analysis made by:
Task: Unloading the ship
Personnel Protective Equipment required and/or recommended:
Sequence of basic job steps: Potential accidents or hazards:
1
X
Recommendation to eliminateor reduce potential hazard:
Ships in Service Training Material A-M CHAUVEL
Job Safety WorksheetUnloading the ship
Please,Would you do an exercise on that subject?
1- Define the nature of the cargo.
2- Step by step identify activities and potential possible hazards.
3- What are the safety remedies you will recommend?
Location Room : :Task, Job : Written by:Revision #:
Date:Revision date:
Protective Personal Equipment ( PPE) required for entry in the local: Safety glassesNon -porous shoes
Long TrousersHard hat
Available Safety Equipment: Nearest fire extinguisher:Nearest shower:
Nearest telephone:Nearest eyes wash fountain:
Nearest safety material :Nearest ….:
Nearest first aid kit:
Hazard Level: Medium LowHigh
Sequences of Steps Potential HazardRecommendationsafety procedures
Add PPErequired
Start-up Procedure
Run Time Procedure
Emergency Shutdown
Ships in Service Training Material A-M CHAUVEL
Job Safety Worksheet
Ships in Service Training Material A-M CHAUVEL
Job Safety WorksheetLocation Date
Task:
Team members:
New: Revised: JSA#:
Leader:Analyzed by:Reviewed by:Approved by:
Specific rules and procedures to be followed:
Sequence of basic job steps Potential accidents or hazardsRecommendations to eliminate orreduce potential hazards
Safety Equipment required to do the job:
Hard hats?Safety shoes,Safety glasses?Cotton gloves?
Work vests?Safety harness?Face shields?Goggles?
Barricades?Fire extinguishers?Lock-out/tag-out?Work permit?
_________?_________?_________?_________?
Articles of the convention
Regulation I
Minimumrequirementsfor seafarers
to workon a ship
Regulation II
Conditionsof
employment
Regulation III
Accommodationrecreational
facilities,food andcatering
Regulation IV
Health protection welfare,
medical careand socialprotection
Regulation V
Complianceand
enforcement
PART A : mandatoryPART B : recommendations
Ships in Service Training Material A-M CHAUVEL
ILO-MLC Convention: 2006
One other simple toolfor scoring risk at work
Job Safety AnalysisKinney Method
A Qualitative Method for scoring Risk at workKinney Method
Ships in Service Training Material A-M CHAUVEL
R (Risk score ) = L x P x C
L (Likelihood of the event)
P (Period of exposure to the hazard)
C (Consequences of the event)
L ( Likelihood of then event )W = 0.1 = Highly unlikelyW = 0.2 = Practically impossibleW = 0.5 = Possible but unlikelyW = 1 = UnlikelyW = 3 = LikelyW = 6 = Very likely
P ( Period of exposure to the hazard )B = 0.5 = Very rare Once per year or lessB = 1 = Rare- A few times per yearB = 2 = Unusual - Once per monthB = 3 = Occasional- Once per weekB = 6 = Frequent- DailyB = 10 = Continuous- Constant
Ships in Service Training Material A-M CHAUVEL
Kinney Method
C ( Consequences of the event )E = 1 = Negligible injuriesE = 3 = Minor injuriesE = 7 = Major injuriesE = 15 = Fatal (1 death)E = 40 = Disaster, more than one death
R ( Risk score ) = L x P x CR < 20 No attention required20 < R < 70 Attention required70 < R < 200 Required actions200< R < 400 Corrective actions requiredR > 400 Stop activities
Ships in Service Training Material A-M CHAUVEL
Kinney Method
Ships in Service Training Material A-M CHAUVEL
Using Monogram
Kinney Method
Exposure
Might well beexpected ofsome time
Likelihood
Quite possiblycould happen
Unusualbut possible
Remotelypossible
Conceivable but very unlikely
Practicallyimpossible
Very rareYearly orless
UnusualOnce permonth
FrequentDaily
Continuous
Tie
Lin
e
Kinney Method (Monogram)
Exposure Possibleconsequences
Risk score
Might well beexpected ofsome time
Likelihood
Quite possiblycould happen
Unusualbut possible
Remotelypossible
Conceivable but very unlikely
Practicallyimpossible
Very rareYearly orless
UnusualOnce permonth
FrequentDaily
Continuous
Fatality>$ 100 000
damage
ManyFatalities
>$ 10 millionsdamage
Minor first aid case
>$ 100damage
Disability>$ 1 000damage
Catastrophe
Disaster
Very serious
Serious
Important
Noticeable
Very high riskConsider discontinuing operation
Substantial riskCorrection required
Possible riskAttention required
RiskPerhaps acceptable8
10
20
100
200
300
400500
40
60
80
Tie
Lin
e
Kinney Method (Monogram)
Exposure Possibleconsequences
Risk score
Might well beexpected ofsome time
Likelihood
Quite possiblycould happen
Unusualbut possible
Remotelypossible
Conceivable but very unlikely
Practicallyimpossible
Very rareYearly orless
UnusualOnce permonth
FrequentDaily
Continuous
Fatality>$ 100 000
damage
ManyFatalities
>$ 10 millionsdamage
Minor first aid case
>$ 100damage
Disability>$ 1 000damage
Catastrophe
Disaster
Very serious
Serious
Important
Noticeable
Very high riskConsider discontinuing operation
Substantial riskCorrection required
Possible riskAttention required
RiskPerhaps acceptable8
10
20
100
200
300
400500
40
60
80
Tie
Lin
e
Kinney Method
Exposure Possibleconsequences
Risk score
Might well beexpected ofsome time
Likelihood
Quite possiblycould happen
Unusualbut possible
Remotelypossible
Conceivable but very unlikely
Practicallyimpossible
Very rareYearly orless
UnusualOnce permonth
FrequentDaily
Continuous
Fatality>$ 100 000
damage
ManyFatalities
>$ 10 millionsdamage
Minor first aid case
>$ 100damage
Disability>$ 1 000damage
Catastrophe
Disaster
Very serious
Serious
Important
Noticeable
Very high riskConsider discontinuing operation
Substantial riskCorrection required
Possible riskAttention required
RiskPerhaps acceptable8
10
20
100
200
300
400500
40
60
80
Tie
Lin
e
Kinney Method
Exposure Possibleconsequences
Risk score
Might well beexpected ofsome time
Likelihood
Quite possiblycould happen
Unusualbut possible
Remotelypossible
Conceivable but very unlikely
Practicallyimpossible
Very rareYearly orless
UnusualOnce permonth
FrequentDaily
Continuous
Fatality>$ 100 000
damage
ManyFatalities
>$ 10 millionsdamage
Minor first aid case
>$ 100damage
Disability>$ 1 000damage
Catastrophe
Disaster
Very serious
Serious
Important
Noticeable
Very high riskConsider discontinuing operation
Substantial riskCorrection required
Possible riskAttention required
RiskPerhaps acceptable8
10
20
100
200
300
400500
40
60
80
Tie
Lin
e
Kinney Method
Exposure Possibleconsequences
Risk score
Might well beexpected ofsome time
Likelihood
Quite possiblycould happen
Unusualbut possible
Remotelypossible
Conceivable but very unlikely
Practicallyimpossible
Very rareYearly orless
UnusualOnce permonth
FrequentDaily
Continuous
Fatality>$ 100 000
damage
ManyFatalities
>$ 10 millionsdamage
Minor first aid case
>$ 100damage
Disability>$ 1 000damage
Catastrophe
Disaster
Very serious
Serious
Important
Noticeable
Very high riskConsider discontinuing operation
Substantial riskCorrection required
Possible riskAttention required
RiskPerhaps acceptable8
10
20
100
200
300
400500
40
60
80
Tie
Lin
e
Kinney Method
Ships in Service Training Material A-M CHAUVEL
Kinney Method
From risk score tojustification score
Shall we invest to prevent an accident ?
Risk score
Very high risk
Substantial risk
Definite risk
RiskPerhaps acceptable8
10
20
100
200
300
400500
40
60
80
Justificationfactor
$300
$3 000
$30 000
$300 000
$1 000 000
Smallreduction
More effective
Eliminate
Riskreduction
Costs forcorrection
10%
25%
50%
75%
100%
Highlyworthwhile
Justified
Of doubtfulmerit
2
60
40
20
10
6
Ships in Service Training Material A-M CHAUVEL
Tie
Lin
e
Kinney Method (Monogram)
Risk score
Very high risk
Substantial risk
Definite risk
RiskPerhaps acceptable8
10
20
100
200
300
400500
40
60
80
Justificationfactor
$300
$3 000
$30 000
$300 000
$1 000 000
Smallreduction
More effective
Eliminate
Riskreduction
Costs forcorrection
10%
25%
50%
75%
100%
Highlyworthwhile
Justified
Of doubtfulmerit
2
60
40
20
10
6
Ships in Service Training Material A-M CHAUVEL
Tie
Lin
e
Kinney Method
Risk score
Very high risk
Substantial risk
Definite risk
RiskPerhaps acceptable8
10
20
100
200
300
400500
40
60
80
Justificationfactor
$300
$3 000
$30 000
$300 000
$1 000 000
Smallreduction
More effective
Eliminate
Riskreduction
Costs forcorrection
10%
25%
50%
75%
100%
Highlyworthwhile
Justified
Of doubtfulmerit
2
60
40
20
10
6
Ships in Service Training Material A-M CHAUVEL
Tie
Lin
e
Kinney Method
Risk score
Very high risk
Substantial risk
Definite risk
RiskPerhaps acceptable8
10
20
100
200
300
400500
40
60
80
Justificationfactor
$300
$3 000
$30 000
$300 000
$1 000 000
Smallreduction
More effective
Eliminate
Riskreduction
Costs forcorrection
10%
25%
50%
75%
100%
Highlyworthwhile
Justified
Of doubtfulmerit
2
60
40
20
10
6
Ships in Service Training Material A-M CHAUVEL
Tie
Lin
e
Kinney Method
Ships in Service Training Material A-M CHAUVEL
Qualitative Risk Analysis
Risk Analysis Tools
The most widely used analytical approach in risk assessment: - Probability data is not required. - Only estimated potential loss is used.
Most qualitative risk analysis methodologies make use of a interrelated elements:
- Hazards or Threats. - Asset Vulnerability. - Controls measures (Countermeasures).
Qualitative Risk Analysis
Ships in Service Training Material A-M CHAUVEL
Ships in Service Training Material A-M CHAUVEL
5.0 Classify each event according its
probability of occurrence
3.0 Repeat the evaluation to each step of the activity or process
1.0 Identify all potential hazards linked to the
activity or process
6.0 Determinate if the risk is
acceptable or not
2.0 Evaluate the risks link in regard to hazards
for the first step
7.0 Use the results indecision making
4.0 Classify each event according its
potential consequences
Qualitative Risk AnalysisProcess
1- Rank the severity of consequences.
2- Rank the “probability” of an incident or an accident occurrence
3- Use matrix to determine if risk is acceptable and…
4- Repeat as necessary for all phase hazard / target combinations.
Ships in Service Training Material A-M CHAUVEL
Qualitative Risk AnalysisThe steps in assessing risk are :
Ships in Service Training Material A-M CHAUVEL
1- Rank Severity of Consequences
Category
Consequences
ICatastrophic
IICritical
IIIMarginal
IVNegligible
PersonnelIllnessInjury
Death
Several injuryor severe
occupationalillness
Minor injuryor minor
occupationalillness
No injury orillness
EquipmentLoss (€)
> 1M
250Kto1M
1Kto
250K
<1K
DownTime
> 4 months
2 weeksto
4 months
1 dayto
2 weeks
<1day
AssetsLoss
EnvironmentalEffect/Impact
Long-term (5 years or greater) or requiring
> €1 M to correct and/or in penalties
Medium-term(1-5 yrs)or requiring €250K- 1M
to correct and/orin penalties
Short-term(<1 yr)or requiring €1K- 250K
to correct and/orin penalties
Damage readily repairedor requiring <€1Kto correct and/or
in penalties
Valuesas for
equipmentloss
Matrix table
1- Rank the severity of consequences.
2- Rank the “probability” of an incident or an accident occurrence
3- Use matrix to determine if risk is acceptable and…
4- Repeat as necessary for all phase hazard / target combinations.
Ships in Service Training Material A-M CHAUVEL
Qualitative Risk AnalysisThe steps in assessing risk are :
Level
F
E
D
C
B
A
DescriptiveWord
Frequent
Probable
Occasional
Remote
Improbable
Impossible
Definition
Likely to occur repeatedlyin system life cycle
Likely to occur several timesin system life cycle
Likely to occur sometimesin system life cycle
Not likely to occur in system life cycle, but possible
So unlikely it can be assumedoccurrence may not be experimented
Physically impossible to occur
Ships in Service Training Material A-M CHAUVEL
2- Rank Probability of occurrence
1- Rank the severity of consequences.
2- Rank the “probability” of anIncident or an accident occurrence
3- Use matrix to determine if risk is acceptable
4- Repeat as necessary for all phase hazard / target combinations.
Ships in Service Training Material A-M CHAUVEL
Qualitative Risk AnalysisThe steps in assessing risk are :
Ships in Service Training Material A-M CHAUVEL
3- Is Risk Acceptable ?
I- Catastrophic
II- Critical
III- Marginal
IV- Negligible
Severity ofconsequences A
ImpossibleB
ImprobableC
RemoteD
OccasionalE
ProbableF
Frequent
Probability of Occurrence of each individual event
Imperative tosuppress riskto lower level
Operation requires writtenlimited waiver endorsedby management
Operationpermissible
Personnel must not be exposed to hazards in both zones
Probability of the event
Veryunlikely
UnlikelyMay
happenLikely
Certain orimminent
1 2 3 4 5
Delay only 1 1 2 3 4 5
Minor injury 2 2 4 6 8 10
Major injury 3 3 6 9 12 15
Single fatality 4 4 8 12 16 20
Multiple fatality 5 5 10 15 20 25
Potentialconsequences
Potential risk analyzed : (an Injury , Fatality… )
Ships in Service Training Material A-M CHAUVEL
Qualitative Risk AssessmentS
eve
rity
Likelihood
Veryunlikely
UnlikelyMay
happenLikely
Certain orimminent
Probability ofthe event
1 2 3 4 5
Minor injury 2 4 6 8 10
Major injury 3 6 12 15
Single fatality 4 8 12 16 20
Multiple fatality 5 10 15 20 25
Delay only
Impact
Se
veri
ty
Likelihood
9
( For individual event )
Qualitative Risk Assessment
Ships in Service Training Material A-M CHAUVEL
Example of matrix :
Riskestimation
Qualitativescore
Moderate7 to 10
High11 to 16
Very high17 to 25
Low1 to 6
Risk Assessment ( Matrix 5x5 )
Ships in Service Training Material A-M CHAUVEL
Interpretation of the risk
Ships in Service Training Material A-M CHAUVEL
Vulnerability to threat
Veryhigh
High Moderate Low
4 3 2 1
Devastating 4 12 8 4
Severe 3 9 6 3
Noticeable 2 6 4 2
Minor 1 3 2 1
Impactof loss
Potential risk analyzed :
12
8
4
( For individual event )
16
Risk Assessment ( Matrix 4x4 )Identification of the level of risk
Risk rating interpretationQualitative
score
These risks are moderate.The countermeasures should be plannedand implemented in the near future
3 to 7
These risks are low.The implementation of countermeasures may betaken in consideration, but are of less urgencythan the above risks
1 to 2
These risks are high.The countermeasures should be implementedas soon as possible
8 to 16
Ships in Service Training Material A-M CHAUVEL
Interpretation of the riskRisk Assessment ( Matrix 4x4 )
Devastating 4
Severe 3
Noticeable 2
Minor 1
Ships in Service Training Material A-M CHAUVEL
Risk Assessment ( Matrix 4x4 )Identification of the level of risk
Vulnerability to threat
Veryhigh
High Moderate Low
4 3 2 1
12 8 4
9 6 3
6 2
3 2 1
Impactof loss
Potential risk analyzed :
12
8
4
( For individual event )
16
4
Risk rating interpretationQualitative
score
These risks are moderate.The countermeasures should be plannedand implemented in the near future
These risks are low.The implementation of countermeasures may betaken in consideration, but are of less urgencythan the above risks
1 to 2
These risks are high.The countermeasures should be implementedas soon as possible
8 to 16
Ships in Service Training Material A-M CHAUVEL
Interpretation of the riskRisk Assessment ( Matrix 4x4 )
3 to 7
1- Rank the severity of consequences.
2- Rank the “probability” of an accident’s occurrence
3- Use matrix to determine if risk is acceptable
4- Repeat as necessary for all phase hazard & target combinations.
Ships in Service Training Material A-M CHAUVEL
Qualitative Risk AnalysisThe steps in assessing risk are :
Ships in Service Training Material A-M CHAUVEL
Risk Analysis Tools
Ships in Service Training Material A-M CHAUVEL
“What-if” Analysis
- 1 Postulate potential problems that may result in accidents or affect system performance.
“What-if” is a brainstorming approach that uses broad, loosely structured questioning to :
- 2 Ensure that appropriate safeguards against those problems are in place.
Ships in Service Training Material A-M CHAUVEL
“What-if” Analysis (WIF)
Generally applicable for almost every type of risk assessment application, especially those dominated by relatively…
Most common uses
Occasionally used alone, but most often used to supplement other structured techniques (especially checklist).
…simple failure scenarios.
1.0 Define theSystem or
Activity
5.0 Subdivide the elements of the System or Activity
(If necessary)
3.0 Subdivide theSystem or Activity
for analysis
4.0 Generate What-if questions for each element of theSystem or Activity
6.0 Respond to thequestions“What-if”
Ships in Service Training Material A-M CHAUVEL
“What-if” Analysis
2.0 Define theproblems
for the analysis
7.0 Use the results in decision making
Process
Ships in Service Training Material A-M CHAUVEL
“What-if” Analysis
Answers
- Immediate effect on vessel condition…
- Potentially leading to an accident…
- Actual safeguards will fail…
Questions
- What if a specific accident occurs?
- What if a specific system fails?
- What if a specific human error occurs?
- What if a specific external event occurs?
- …
“What-if” AnalysisImmediate
system condition
Reduced air flow through the compressor, affecting its performance
What if…
1- The intake air filter begins to plug
Ultimateconsequences
Inefficient compressor operation, leading to excessive energy use and possible compressor damages.
Low or no air flow to equipment, leading to functional inefficiencies and possibly outages.
Summary of the “What-if” Review of a Vessel’s Compressed Air System
2- Someone leaves a safety valve open
High air flow rate through the open valve to the atmosphere
Low or no air flow to equipment leading to functional inefficiencies and possibly outages.
Potential for personnel injury from escaping air or blown debris.
Small drain line would divert only a portion of the air flow, but maintaining pressure would be difficult.
Ships in Service Training Material A-M CHAUVEL
Safeguards
Pressure/vacuum gauge between the compressor and the intake filter.
Annual replacement of the filter.
Rain cap and screen at the air intake
Recommendations
Make checking the pressure gauge reading part of someone’s weekly round ORReplace the local gauge with low pressure switch that alarms in a manned area.
Ships in Service Training Material A-M CHAUVEL
The Structured What - If checklist (WIFT) technique is a method of identifying hazards based on the use of brainstorming.
WIFT is a more structured form of analysis, which may be seen as a less rigorous but it is a quicker alternative to HAZOP.
WIFT an alternative to HAZOP:
“What-if” Analysis
Ships in Service Training Material A-M CHAUVEL
• It is very flexible, and applicable to any type of installation, operation or process, at any stage of the lifecycle.
• It uses the experience of operating personnel as part of the team.
• It is quick, because it avoids repetitive consideration of deviations.
The Strengths of SWIFT are:
“What-if” Analysis
Ships in Service Training Material A-M CHAUVEL
• As it works at system level: - Some hazards may be omitted, - It is difficult to audit.
• Adequate preparation of a checklist in advance is critical for the quality of the review.
• Its benefit depends on the: - Experience of the leader and - Knowledge of the team.
The Weaknesses of SWIFT are :
“What-if” Analysis
Ships in Service Training Material A-M CHAUVEL
“What-if” Analysis
- Likely to miss some
potential problems.
- Difficult to audit for
detail elements.
- Traditionally provides only
qualitative information.
Limitations
AccidentCause
Ships in Service Training Material A-M CHAUVEL
Root Cause
Cause
Cause
Cause
Risk Analysis Tools
Used to search the root cause
in Accident Investigation
AccidentCause
Ships in Service Training Material A-M CHAUVEL
Root Cause
Cause
Cause
Cause
Risk Analysis Tools
Used to reach the potential causes
of an Accident
The 5 Whys analysis is a simpler form ofFault Tree analysis for investigations of
specific accidents as opposed to
chronic problems.
It is a technique use to identifiesroot causes of the eventby asking the questionwhy events occurred or
conditions existed.
The “5 Whys”
Ships in Service Training Material A-M CHAUVEL
The causes ofthe event
are identifiedby asking
the questionsuntil
they become absurdor because we have
no more ideasabout the problem.
Why…?Where arethe roots
Ships in Service Training Material A-M CHAUVEL
Root Cause AnalysisThe “5 Whys”
From Top
To roots
“5 Whys” Principles
Ships in Service Training Material A-M CHAUVEL
Top Eventcondition
Sub-Eventcondition
Sub-Eventcondition
Sub-Eventcondition
Sub-Eventcondition
Sub-Eventcondition
Sub-Eventcondition
RootCause
Why ?
Why ?
Why ?
Why ?Why ?
Ships in Service Training Material A-M CHAUVEL
Top Eventcondition
Sub-Eventcondition
Sub-Eventcondition
Sub-Eventcondition
Sub-Eventcondition
Sub-Eventcondition
Sub-Eventcondition
Sub-Eventcondition
RootCause
Sub-Eventcondition
Sub-Eventcondition
RootCause
5
3
2
1
4 Sub-Eventcondition
RootCause
Why ?
Why ? Why ?
Why ?
Why ?Why ?
Why ? Why ?
Why ?Why ?
“5 Whys” Principles
Ships in Service Training Material A-M CHAUVEL
1. "Why the robot stop?" The circuit is overloaded, causing a fuse to blow.
2. "Why the circuit overloaded?" There was insufficient lubrication on the bearings,
so they locked up.
3. "Why the insufficient lubrication on the bearings?" The oil pump on the robot is not circulating sufficient oil.
4. "Why the pump not circulating sufficient oil?"
The pump intake is clogged with metal shavings.
5. "Why the intake clogged with metal shavings?" Because there is no filter on the pump.
“5 Whys” A case
Ship sunk?Ship sunk? Collision
Lack of attention of the deck officer
Collision?Collision?
Lack of attention?Lack of attention? Alcohol level in his blood
Alcohol?Alcohol? Celebration prior watchkeeping
Celebration?Celebration? Radio told him “he is father”
The master let him take over the bridge ?
The company did not plan his shore stay period for the birth of his child?
Ships in Service Training Material A-M CHAUVEL
Why ?
Why ?
Why ?
Why ?
Why ?
Why ?
- Brainstorming is time consuming.
- Results are not reproducible or
consistent.
- Some root causes may not
be identified.
“5 Whys”
Ships in Service Training Material A-M CHAUVEL
Limitations
Resulting sub-events and conditions should be at or near the root causes of the event.
More detailed evaluation may be necessary
to reach management system root causes.
Judgment and experience are key factorsin selecting the right level of evaluation and
to achieve the completeness of results.
The “5 Whys”
Ships in Service Training Material A-M CHAUVEL
Conclusions
The results are not reproducible or consistent, but the application is auditable.
Twovertebrascrushed
Fall 1st. stepof the ladder
Climbthe ladder
Dizziness
Lossequilibrium
Installthe ladder
MedicalShoes onboth feet
Feelconfident
Both feetoperated
Walk withoutshoes
Sugarlevel
Request tolook at thewall paper
Fungicontamination
Airconditioneddefective
High Temp.& Humidity
Sleepingeffect
Anti paintreatment
Carpethygiene
Overweight
Ships in Service Training Material A-M CHAUVEL
“5 Whys” A case
Ships in Service Training Material A-M CHAUVEL
Risk Analysis Tools
A technique that visualize
how logical relationships exist between :
Ships in Service Training Material A-M CHAUVEL
Fault Tree (FTA)
Equipment failures Human errors
External events
-when combined- cause a specific incident/accident.
Developed first in the aerospace industries.Have found uses in many other areas,
most recently in software analysis.
Fault tree operate by :
- Developing a list of the faults that can occur in a system and
- Attempting to trace them back to their root causes.
Ships in Service Training Material A-M CHAUVEL
Fault Tree
While this method can be used to show complicated interactions,
it is still subject to overlooking some aspects of the system as the answers are mostly enumerated.
It is advisable to combine this methodwith another approach
to ensure the completenessof the analysis.
Ships in Service Training Material A-M CHAUVEL
Fault Tree
Creating a Fault Tree
Ships in Service Training Material A-M CHAUVEL
9- Identifycausal factors
1- Define event of interest
7- Stop branchdevelopment
6- is branchcredible?
8- Is modelsufficientlydeveloped?
5- Use data toDetermine
credibility of branches
2- Define nextlevel of the tree
3- Develop questionsto examine
credibility of branches
4- Gather data toanswer questions
Yes
Yes
No
No
Generally applicable for almost every typeof risk assessment dominated byrelatively complex combinations
of these events.
But, used most to :
- Understand the causal factors of an event. - Determine the potential root causes
of the event.
Ships in Service Training Material A-M CHAUVEL
Fault TreeMost common uses
5.0 Solve thefault tree for thecombinations of
events contributingto the event
7.0 Performquantitative analysis
If necessary
3.0 Define the tree structure
4.0 Explore eachbranch in successive
levels of details
6.0 Identify importantdependent failure
potentials and adjustthe model appropriately
Ships in Service Training Material A-M CHAUVEL
Fault Tree
2.0 Define thetop event
for the analysis
8.0 Use the results indecision making
1.0 Define theSystem
Process
Fire orExplosion
Externalhazards
Contact orcollision
Flooding …
F1 F2 F3 F4
OrAndEvent BEvent A
B2B1A2A1
Event trees For consequences
Incident/Accident
categories
IncidentSub-categories
F1 - Engine roomF3 - Accommodation
………
Faults trees for direct cause and initiating events
Ships in Service Training Material A-M CHAUVEL
Risk Contributing FactorFault Tree
Fault Tree
Ships in Service Training Material A-M CHAUVEL
Projectorlamp
shutdown
Power outage
Unresolvedlamp failure
Inadvertentshutdown
Wiringfailure
Basic lamp
failure
No spare lamp
Internal
External
Operator error
Unplug
And
Or
Fault Tree
Ships in Service Training Material A-M CHAUVEL
Projectorlamp
shutdown
Power outage
Unresolvedlamp failure
Inadvertentshutdown
Wiringfailure
Basic lamp
failure
No spare lamp
Internal ExternalOperator
errorUnplug
And
Or
Cupleaks
Wrongparticlesize
Wrongmaterialexpansionrate
Lowdensity
Improper wallthickness
Deflection forceratio too high
Stackingdamage
Stacking stop heightincorrectly specify
Punctured
Excessporosity
Wrong particle size
Wrong material expansion rate
OrAndLegend :
Fault Tree
Ships in Service Training Material A-M CHAUVEL
Fault Tree
Engine failsto operate
Basicfailure of the
propeller
Basicfailure of the
engine
Contaminatedfuel in bunker
tanks
Onboard fuelcleanup system
fails
Fuel supply to engine is
contaminated
Vessel losespropulsion
Enginestops
And
Or
Enginecontrol failure
Enginefailure
Bearingfailure
Fuelsupply failure
Gate : And
Gate : Or
Ships in Service Training Material BRENNAN & PEACHEY
Enginecontrol failure
Enginefailure
Bearingfailure
Fuelflow failure
Contaminatedfuel
Fuelsupply failure
Gate : And
Gate : Or
Ships in Service Training Material BRENNAN & PEACHEY
Exercise
Ships in Service Training Material A-M CHAUVEL
ExerciseCompletethe tree
Risk Analysis Tools
Ships in Service Training Material A-M CHAUVEL
ExerciseCompletethe tree
Risk Analysis Tools
The Causes
Fuelsupply failure
Contaminatedfuel
Fuelfilter failure
Enginecontrol failure
Enginefailure
Bearingfailure
Bunker fuelLeak from
heating coils Water
condensationMechanical
failureElectrical
failure
Fuelflow failure
Contaminatedfuel
Fueltank failure
Fuelpump failure
Fuel supplypipe failure
Fuelsupply failure
Gate : And
Gate : Or
Ships in Service Training Material BRENNAN & PEACHEY
- Narrow focus. - Art as well as science.
- Quantification requires significant expertise.
- Narrow focus. - Art as well as science.
- Quantification requires significant expertise.
Ships in Service Training Material A-M CHAUVEL
Fault TreeLimitations
Ships in Service Training Material A-M CHAUVEL
Risk Analysis Tools
Ships in Service Training Material A-M CHAUVEL
Risk Analysis Tools
Ships in Service Training Material A-M CHAUVEL
Event Tree (ETA)
A technique that develops models of thepossible outcomes of an initiating event.
The models explore how: - Safeguards,
- External influences, - Lines of assurance (LOA),
affect the path of the event chains.
Ships in Service Training Material A-M CHAUVEL
Event Tree
Applicable for almost any type
of risk assessment but,
used most effectively to
events where
multiple safeguards are in place
as protective features
to avoid escalation.
Most common uses
1.0 Define theSystem or Activity
6.0 Summarizeresults
3.0 Define LOA and physicalphenomena
4.0 Defineaccident
scenarios
5.0 Analyze accidentsequence outcomes
Ships in Service Training Material A-M CHAUVEL
Event Tree
2.0 Define theInitiating event
7.0 Use the results in decision making
Process
Ships in Service Training Material A-M CHAUVEL
Event Tree Terminology
Initiating event :
The occurrence of some failure with the potential to produce an undesired consequence. An initiating event is sometimes called
an incident.
Line of assurance (LOA) :
A protective system or human actionthat may respond to the initiating event.
The following terms are commonly used in ETA
Ships in Service Training Material A-M CHAUVEL
Event Tree Terminology
Branch point :
Graphical illustration of (usually) two potential outcomes when a line of assurance is
challenged.
Accident sequence or scenario :
One specific pathway through the event tree from the initiating event to an undesired
consequence.
The following terms are commonly used in ETA
Ships in Service Training Material A-M CHAUVEL
Event Tree Scenario & Sequence
FS : Failures of LOALOA : Line of Assurance : Success of LOA
F
S
LOA 2LOA 1 LOA 3
Consequence 4
Consequence 2
Consequence 1
F
S
Initiating
EventConsequence 3
Branchpoint
Branchpoint
Branchpoint
F
S
Ships in Service Training Material A-M CHAUVEL
Replacementstill not OK
ReplacementOK
Replacementstill not OK
ReplacementOK
Charliereplaces
Instructorreplaces
Instructorinept
Charlieunavailable
Spareavailable
No spare available
Projectorlamps fails
F
S
F
S
F
F
FS FailureSuccess
Event Tree Scenario & Sequence
Leak or rupture of piping containing flammable material
X
Yes
Ships in Service Training Material A-M CHAUVEL
AFlammablematerial spill,but no fire
Complete lossof facility ?
No
Event Tree Scenario & Sequence
ExerciseCompletethe tree
Initiatingevent Ignition
preventedPortable fire
extinguishersCO2
systemSea water
system
Accident sequence Outcomes
Fire extinguished with :
Other Line Of Assurance
Initiatingevent Ignition
preventedPortable fire
extinguishersCO2
systemSea water
system
Accident sequence Outcomes
Leak or rupture of piping containing flammable material
D
C
B
A
E
Flammablematerial spill,but no fire
Minor firedamageNo loss of systemavailability
Medium firedamagePotential loss ofSystem availability
Major firedamageLoss of systemavailability
Complete lossof facility
P1
P2
P3
P4
Yes
No
Yes
No
Yes
NoYes
No
Ships in Service Training Material A-M CHAUVEL
Fire extinguished with :
Other Line Of Assurance
Escalation process
Event Tree Scenario & Sequence
Total loss
Fatal impact
No fatal impact
Critical damage
Major damage
Escalation
Minor damage
Scenario
Ships in Service Training Material A-M CHAUVEL
Fire / explosion
Where?
EffectEvent Consequence
Fire / explosion
serious casualty
Accom-
modation
0,20
Machinery spaces0,72
Vehicle
deck0,08 Major damage 0,70
Total loss 0,30
Major damage 0,80
Total loss 0,20
Major damage 0,70
Total loss 0,30
No fatal impact 0,93
Fatal impact 0,07
No fatal impact 0,57
Fatal impact 0,43
No fatal impact 0,92
Fatal impact 0,08
Major damage
0,67
Escalation
0,33
Major damage
0,96
Escalation
0,04
Major damage
0,71
Escalation
0,29
Fire / Explosion Scenario
Ships in Service Training Material A-M CHAUVEL
Remains upright 0,88
Fatal impact 0,19
Non-fatal impact 0,81
Slow sinking 0,25
Rapid capsize 0,25
Minor damage 0,5
Major damage 0,5
Remains upright 0,5
Slow capsize 0,12
Minor damage 0,5
Major damage 0,4
Destruction 0,1
Impact only
0,78
Flooding
0,19
Fire
0,03
Fire
0,03
Flooding
0,06
Impact only
0,91
Struck
ship0,5
Striking
ship
0,5
Serious
casualty
0,12
Minor incident
0,88
Collision
under way0,97
Striking at berth
0,03
Collision
incident
Collision Scenario
Below vehicle deck
0,16
Slow sinking 0,2
Rapid capsize 0,1
Remains afloat 0,7
Through hull
0,03
Stern door
0,56
Blow door
0,28
Into bridge / superstructure
0,27
Through open doors
0,19
Through down-flooding openings
0,18
Flooding
incident
Through bow door
0,67
Through stern door
0,03
Slow sinking 0,2
Rapid capsize 0,7
Remains afloat 0,1
Remains afloat 0,8
Side door
0,16
Slow sinking 0,2
Due to wave damage
0,47
Remains afloat 0,8
Slow sinking 0,2
Flooding Scenario
Second levelof safeguardsLOA 2
0,10P Failure
First level of safeguardsLOA 1
Initiatingevent
0.4 /yearFrequency ofInitial event
0,90P Success
0,05P Failure
0,95P Success
Outcome 1 :First level succeededFreq = (0.4)(0.95 ) = 0.380 /year
Outcome 3 :Both level FailedFreq = (0.4)(0.05)(0.10) = 0.002 /year
Outcome 2 : First level FailedSecond level succeededFreq = (0.4)(0.05)(0.90) = 0.018 /year
Ships in Service Training Material A-M CHAUVEL
Event Tree (case 1)
Second levelof safeguardsLOA 2
0,10P Failure
First level of safeguardsLOA 1
Initiatingevent
0.4 /yearFrequency ofInitial event
0,90P Success
0,90P Failure
0,10P Success
Outcome 1 :First level succeededFreq = (0.4)(0.10 ) = 0.04 /year
Outcome 3 :Both level FailedFreq = (0.4)(0.90)(0.10) = 0.04 /year
Outcome 2 : First level FailedSecond level succeededFreq = (0.4)(0.90)(0.90) = 0.32 /year
Ships in Service Training Material A-M CHAUVEL
Event Tree (case 2)
Ships in Service Training Material A-M CHAUVEL
Event Tree
- Limited to one initiating event.
- Can overlook subtle system dependencies.
Limitations
Ships in Service Training Material A-M CHAUVEL
Risk Analysis Tools
Hazardous Event
FAULT TREE( Causes )
Ha
zard
sEVENT TREE
( Consequences )
Es
cala
tio
ns
Sequences of faults & causesleading to a hazardous event
Sequences of events & failures leadingto the escalation of a hazardous event
Ships in Service Training Material A-M CHAUVEL
Bow Tie
IncidentAccident
IncidentsFire or Explosion
Act of piracyAct of terrorist
Equipment failuresShip collision
…
AccidentsPersonnel InjuryPersonnel illness
UnwantedUnwantedEventEvent
Bow Tie
Ships in Service Training Material A-M CHAUVEL
ConsequencesConsequences
SocialLoss of livesLoss of jobs
EnvironmentalAir pollutionWater pollution,…
EconomicLoss of the shipCargo damagesShip damagedShip detentionInsurance PremiumCompany imageBankruptcy
CausesCauses
ManHuman ErrorsPhysical ConditionsQualifications
Machines, Tools& Equipments
Materials & Furniture
Methods & Procedures
ManagementInternal EnvironmentExternal Environment
1
2
3
4
5
6
7
1
2
3
4
5
6
7
1
2
3
4
5
Safety measure
Safety measure
Safety measureSafety measure
Causes OutcomesReactivecontrols
Hazards Proactivecontrols
Ships in Service Training Material A-M CHAUVEL
Bow Tie
UnwantedEvent
Event TreeFault Tree
Ships in Service Training Material A-M CHAUVEL
Failure Mode & Effect Analysis
Risk Analysis Tools
Used primarily for reviews of mechanical and electrical systems,
vessel steering and propulsion systems.
Used frequently as the basis for defining and optimizing planned equipment maintenance because the method systematically focuses
directly and individually on equipment failure.
Effective for collecting the informationneeded to troubleshoot system problems.
Failure Modes & Effects Analysis
Ships in Service Training Material A-M CHAUVEL
Most common uses
Like a checklist,but a more organized one.
Once the failure have been listed,the consequences of that failure are listed.
Once these information have been collected,possible countermeasures for
each failure are listed.
Ships in Service Training Material A-M CHAUVEL
Failure Modes & Effects Analysis
Like a checklist but a more organized one.
Once the failure have been listed,the consequences of that failure are listed.
Once these information have been collected,possible countermeasures for
each failure are listed.
Ships in Service Training Material A-M CHAUVEL
Failure Modes & Effects Analysis
Ships in Service Training Material A-M CHAUVEL
Rank them according tothe level of riskthey represent
List of failures
List ofconsequences
List of possiblecontrol measures
This providesFailure Modes & Effects Analysis
What can go wrong ?Function failure
Severity Occurrence Detection
Consequences Prevention?Cause
FMEA Principles
Function or Requirement ?
Ships in Service Training Material A-M CHAUVEL
What can be done ?Countermeasures
Risk analysis
What can go wrong ? - No function - Partial or Degraded function - Intermittent function - Unintended function
How badis it ?
How oftendoes it happen ?
How good is the methodat detecting it ?
What arethe effect ?
How this can be preventedor detected ?
What arethe cause (s) ?
FMEA Principles
What are the functions, features or
requirements ?
Ships in Service Training Material A-M CHAUVEL
What can be done ? - Design changes - Process changes - Special controls - Changes in Procedures or Spec.
6.0 Evaluate potential failure modes
capable ofproducing problems
8.0 Transition of the analysis to anotherlevel of resolution
( if useful )
3.0 Choose the typeof FMEA approach
for the study
4.0 Subdivide the system for analysis
7.0 Performquantitativeevaluation
( if necessary )
Ships in Service Training Material A-M CHAUVEL
FMEA
2.0 Define theproblem
for the analysis
9.0 Use the results indecision making
1.0 Define thesystem
5.0 Identify potential failure modes forelements of the
system
Process
ComponentFunction
FailureMode
FailureCause
FailureDetection
End Effect ofFailure
CorrectiveAction
Recom.
Fuel OilPurifier
Electricalfailure
Switchboardfaultor Power generationfault,e.g.. blackout
Alarm channelto ECR forpurifiers failure
-Both purifiers failed
- Possible blackout
- Potential to lead to eventual machinery failure
Re-establishpower supplies
Restart mainengine if stopped
Reset purifieroperation
Service Tankshould be largeenough foradequate periodon full poweroperation.
A separateelectricaldistribution(main / emerge.) isprovided to eachpurifier in theevent of oneswitchboardfailure.
Mechanicalfailure
Loss oflubrication dueto degradedcomponent.
Inadequate orincorrectmaintenance.
IncorrectOperation.
Alarm channelto ECR forpurifiers failure
One purifierfailed,stand by unitavailable
Run up and put stand-by unit on line
Comment :
Human errorcancontributetowards thesefailures
Ships in Service Training Material BRENNAN & PEACHEY
Failure Modes & Effects Analysis
Ships in Service Training Material A-M CHAUVEL
MIL-STD- 1629A
Failure Modes & Effects Analysis
Occurrence (O) - Frequency of the failure.
Severity (S) - Consequences of the failure.
Detection (D) - Ability to detect the failure before it reaches the next step.
FMEA Interpretation
Ships in Service Training Material A-M CHAUVEL
There are three components that help definethe Relative Priority Number concerning failures:
RPN = O x S x D
The 3 components
Minor
Low
Moderate
High
Veryhigh
Effect ofoccurrence
1
2-3
4-6
7-9
10
Rank
Example of Ranking Criteria
Ships in Service Training Material A-M CHAUVEL
Effect ofseverity
RankEffect ofdetection
Minor
Low
Moderate
High
Veryhigh
1-2
3-5
6-7
8-9
10
Veryhigh
high
Moderate
Low
Verylow
1-2
3-4
5-7
8-9
10
Rank
Failure is minor, not more than 2 minutes.Failure will not result / cause the machine down.
Failure will result / cause the machine down less than 25 minutes.This is a remote probability of occurrence during the operation time interval,unscheduled repair needed, quantitative & qualitative of output will be affected. Minor failure frequency is less than 2 times within 1 hour.
An occasional probability of occurrence during operating time interval.Machine down is more than 30 minutes quantity & quality of the output willbe affected. Failure will result / cause disruption to subsequent process.Minor failure frequency is less than 5 times within 1 hour.
Failure will result / cause the equipment damage and unscheduled repairs.Machine down more than 2 hours ( less than 6 hours ), a moderateprobability of occurrence during operating time the failure is minor alarmor stop less than 5 minutes quantity and quality of output will affect,unscheduled repairs need and frequency minor failure is more than 5 timeswithin 1 hour.
Failure will result / cause disruption stop. Machine down is more than 6 hours.This is unlikely probability of occurrence during the operating time interval( Once every 2 months ) or high probability of occurrence during operation.More than 10 times within 1 hour for minor down.
Description
Minor
Low
Moderate
High
Veryhigh
Effect ofoccurrence
1
2-3
4-6
7-9
10
Rank
Occurrence Ranking Criteria
Ships in Service Training Material A-M CHAUVEL
Severity Ranking Criteria
Ships in Service Training Material A-M CHAUVEL
Failure is of a minor nature and would cause the real effect on product.The lead time required from the part is order ( no more 2 hours ) or lookingin store and for installation & repair are completed not more than 15 minutes.
The lead time required from the part is order ( no more 3 hours ) orlooking in store and for installation and repair are completed not morethan 90 minutes.
The lead time required from the part is order ( more than 3 hours ) orlooking in store and for installation and repair are completed morethan 5 hours.
The lead time required from the part is order ( more than 4 hours ) orlooking in store and for installation and repair are completed morethan 12 hours.
Failure will result in the shutting down due to late shipment( more than 2 days ) and no stock keep, or installation and repairingmore than 24 hours.
Description
Minor
Low
Moderate
High
Veryhigh
Effect ofseverity
1-2
3-5
6-7
8-9
10
Rank
Ships in Service Training Material A-M CHAUVEL
Low probability that the defect or equipment warning signals will be detected.More than 6 months
Equipment warning signals will be detected.More than 3 months but less than 6 months.
Equipment warning signals will be detected. Not more than 1 month.
High probability that the defect will be detected more likely and equipmentwarning signals will be detected to detect the existence of a defect.Mostly less than 1 week.
Very high probability that the defect will be detected.Equipment warning signals will be detected.Not more than 1 day.
Description
Veryhigh
High
Moderate
Low
Verylow
Effect ofdetection
1-2
3-4
5-7
8-9
10
Rank
Detection Ranking Criteria
Failure Effect on :Item
identificationFunction
Failuremode
Failurecause
Component orFunctional assembly
Next higherassembly System
Failuredetectionmethod
Switch
InitiatesMotorpowerfunction
Fails toopen
Releasespringfailure
NoneMaintenanceenergy tocircuit relay
Maintainsenergy topower circuitthrough relay
Motor continuesto runSmoke visualwhen powercircuit wireoverheats
Battery # 2( Relay circuit )
Providesrelayvoltage
Fails toprovide adequate power
Depletedbattery
None
Battery getshot anddepletes
Fails to operate relaycircuit
System failsto operate
Motor notrunning
Relay coil
Closesrelaycontactswhenenergized
Coil fails toproduceEMF
Coilshortedor open
Does notclose relaycontacts
Does notEnergizepower circuit
System failsto operate
Motor notrunning
Motor
Providesdesiredmechanical event
Fails tooperate
Motorshorted
Motor overheats
High currentin powercircuit
Overheat PwrCircuit breakerfails to openand switch orrelay fails
Smoke visual
Ships in Service Training Material A-M CHAUVEL
Failure Modes & Effects Analysis
Ships in Service Training Material A-M CHAUVEL
- Examination of human error is limited.
- Focus is on single event initiator of problems.
- Examination of external influences is limited.
- Results dependent on the mode of operation.
LimitationsFailure Modes & Effects Analysis
Ships in Service Training Material A-M CHAUVEL
Hazard & Operability Analysis
Risk Analysis Tools
A methodology for safety analysis that is highly rigorous & precise, involve :
- A system model where each componentis described with a list of attributes
that support the function of a component.
- A list of guide words with well defined meanings is then applied to each attribute to determine
the effect of any deviationfrom the normal operating function.
Hazard Operability
Ships in Service Training Material A-M CHAUVEL
Ships in Service Training Material A-M CHAUVEL
HAZOP : Guide Words
Errors
Other than
Reverse
Less
Consequences
Skip Part of
More
As well as
Out of sequence
Actions
Safeguards
Ships in Service Training Material A-M CHAUVEL
Primarily for identifyingsafety hazards and
operability problems ofcontinuous process systems,
especially fluid and thermal systems.
Also used to review
procedures and sequential operations.
Hazard OperabilityMost common uses
6.0 Developrecommendations
(if necessary)
8.0 Repeat step 5 through 9
for the remaining deviations
3.0 Apply the firstdeviation to item
What are the consequences?
4.0 Identify all of the causes
of the deviation
7.0 Summarize the information collected
for this deviation
Ships in Service Training Material A-M CHAUVEL
2.0 Define thedesign intent
of the item
9.0 Repeat step 3 through 9 for the remaining
items
1.0 Identify theitem
5.0 Identify engineeringand administrative
controls thatprotect the item
HAZOPProcess
Deviation Causes Consequences Safeguards Recommendations
HAZOP review of Barge Filling Operations at a Typical Small Fueling Terminal
Item
1.0 Line from a storage Tank to the Barge Manifold (Including Hose ) Part 2
Reverseflow
No credible causes(maximum level in barge tanks is belowfacility grade level
Typical arrangement had a check valve atthe discharge of theloading pump if a centrifugal pump is used.
1.4
Highpressure
Lower flow ratebecause of adeadheaded pump(see deviation 1.2).
Thermal expansion ofliquid isolated betweenclosed valves.
Potential leak or rupture of the piping (see deviation 1.10)
Regulations specify themaximum allowablepressure for transferoperations.
Relief valve at the discharge of gearpumps (Typically installed).
Lines typically drain tobarge tanks beforevalves are closed,minimizing thepotential for isolatingliquid full times.
Recommendation:
Verify that a reliefvalve is required at thedischarge of positivedisplacement pumpsthat are capable ofdamaging the pipingsystem ( including thetransfer hose) if a deadheading occurs.
1.7
Ships in Service Training Material
HAZOP Worksheet
Item # Deviation Causes Consequences Safeguards Rcd.
1.1 Missing No missing steps were identified
Step : Review appropriate documents, check logs, etc
1.2 Skip
Communication barrierswith foreign languages
Many inspectors agencieson board do not allowadequate time tocommunicate expectations
Time constraints on vesseltrying to leave port quicklywith commercial pressureto perform rapid inspection
Potential to skip later steps becauseCoast Guard expectations are notcommunicated to the crew, creatingthe potential for accident/injury orloss of commerce
Potential for inexperienced crew toperform the test, with the potentialfor accident or injury later in the test
Potential for loss of commerce dueto delay in passing the inspection/drill
Vessel may be held to aninappropriate standard
Flexibility of the C.G. towork with portions of thecrew, so that otherportion of the crew canwork with other agencies
Standardized C.G.expectations that areconducted/communicatedvery frequently
Minimum of 2 C.G. staffmembers at least one being well trained
1.6Out of sequence
No consequence of interest if performed before the drill
1.5 Less Same as skip
Ships in Service Training Material
HAZOP Worksheet
Consequence
Project Description:
PossibleCause(s)
Team members:
ExistingSafeguard
Ref # Recommendations
Minutes by:
Action
Pages:
Guideword
AccountabilityActionRef#
Team leader:
Date
Ships in Service Training Material A-M CHAUVEL
HAZOP Worksheet
- A well-defined system or activity is required.
- Time consuming.
- Focuses on one event causing the deviations.
Ships in Service Training Material A-M CHAUVEL
LimitationsHAZOP
Justificationfactor
Highlyworthwhile
Justified
Of doubtfulmerit
2
60
40
20
10
6
Risk score
Very high risk
Substantial risk
Definite risk
RiskPerhaps acceptable8
10
20
100
200
300
400500
40
60
80
Risk Assessment
Ships in Service Training Material A-M CHAUVEL
Remember…
tools are only tools to help you.
If something is “obvious” it probably doesn’t need a risk assessment to act.
Ships in Service Training Material A-M CHAUVEL
Do not start a new project unless risk analysishas been completed.
Ships in Service Training Material A-M CHAUVEL
Ships in Service Training Material A-M CHAUVEL
Do not start the risk assessment before the intent of the project is clear.
Ships in Service Training Material A-M CHAUVEL
Do not start a risk assessment unless the event of interestis well define and the need recognize by the participants.