0910 Bow Tie Risk Paulo Rheinbolt

8/20/2019 0910 Bow Tie Risk Paulo Rheinbolt

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Objectives

Presentation the Bow-tie methodology basic concepts


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Risk Management

Risk Management is growing in importance because ...Increasing complexity and uncertainty in the work space

Increasing opportunitiesIncreasing stakeholders expectations

Need to optimize management of Upside Risks & Downside RisksNeed to optimize management of Enterprise Risk & Operational Risks


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Risk

Risk: The combination of a event probability and its consequences (ISO/IEC Guia 73).Risk Management: A process to ensure that all significant risks are identified, prioritized, and

managed effectively(DNV).


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THRESHOLD

LIMIT

Inadequate

System

Inadequate

Standards Inadequate

Compliance

Lack of

Control

Personal

Factors Job / System

Factors

Basic

Causes

Substandard

Acts or

Practices Substandard

Conditions

Immediate

Causes

Event

Contact ( or

near) with

energy or

substance

Incident

People

Equipment Material Environment

Loss


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Managing Risk

RiskRecognition

RiskEvaluation

RiskControl

RiskMonitoring

Establish thecontext

Identify all

hazards, threats,& opportunities

Analyze the risks

Evaluate the risksImplement

control plans

Develop control

plans

Review & improverisk management

s stem

Monitor risks& controls

WHAT

MATTERS?

WHAT IS THE

RISK?

SO WHAT? LET’S DO IT!

WHAT DO WE

DO NOW?

IS IT

WORKING?

CAN WE MAKE IT

BETTER?

WHAT CAN GOWRONG

(OR RIGHT)?


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Risk Analysis and Assessment

Decisions

1

2

3

...HAZID

People Qualitative

Analysis

Reputation

Semi-QuantitativeAnalysis

xBenefits

sse s

Environment

QuantitativeAnalysis

ALARP

Costs

Risks Evaluation

Risk Analysis


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Why Bow-tie?

Visualization of the relationship between undesirable event, its

causes, accidental scenarios, the preventive and mitigation

measures to limit their consequences

Demonstrates the effectiveness of existing controls

Structured risk anal sis where uantification is not ossible or

desired

Extremely versatile / Success in various applications

Required multidisciplinary team


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The “Swiss Cheese” Barrier Model


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Prevent Barriers

Inherent

Design Plant

layout

Maintenance &

Inspections

Learningfrom

Events

OperationalProcedures

EffectiveSupervision

Work

ControlRelief andBow-down

System

Audit & SelfRegulation

Management of

Change

Communication

Training &

Competency

Control,

Alarm &

Shut-down

System


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Prevent Barriers

Inherent

Design Plant

layout

Maintenance &

Inspections

Learningfrom

Events



Work

ControlRelief and

Bow-down

System

Audit & SelfRegulation

Management of

Change

Communication

Training &

Competency

Control,

Alarm &

Shut-down

System


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Detect, Control, Mitigate and Recovery Barriers

Mitigate

Limit Effect

(e.g. deluge system)

ControlLimit extent

(e.g. blow-down)

Detect

Gas, Fire,

Pressure Temperature

High - Low

Crisis Management &

Business Recovery

Emergency ResponseEvacuation, Escape and

Rescue

Inherent

DesignPlant layout

Maintenance

& Inspections

Learning

fromEvents



Work

ControlRelief

andBow-

downSystem

Audit &Self

Regulation

Management

of Change

Communication

Training&

Competency

Control,

Alarm&Shut-down

System


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Bow-tie Diagram

What can cause anImportant Event?


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Bow-tie Diagram


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Bow-tie Diagram Construction

Define the Hazard and the Top Event which is the initial consequence

"What happens when the danger is" released "?"

Identify the Threats which are the Top Event causes

"What causes the release of danger?

"How can lost control?

Identify the existing Protection Barriers each Threat- Prevent the Top Event occurrence

- Can be independents or dependents

"How can controls fail?""How can that their effectiveness can be compromised?"


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Identify for each Barrier their Escalation Factors

- Factors that make the Barrier fail

“How can we avoid that the hazard being released?

“How can we keep the control?”

Identify for each Barrier their Escalation Factors Control

- Factors that prevent or minimize the possibility of the Barrier or theRecovery Measures becomes ineffective

"How to ensure that the controls will not fail?"

Identify the consequences- Top Event could have several consequences


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Identify the Recovery Measures

- Factors that make the barriers fail

"How can we limit the severity of the event?”

"How can we minimize the effects?"

Identif for each Recover Measure their Escalation Factors and

Escalation Factors Controls

For each Barrier, Recovery Measures and Escalation Factors Controls

identify the Critical Safety Tasks


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Critical Safety Tasks

Tasks prevent and/or minimize the possibility of the Barrier, the Escalation

Factor Control or the Recovery Measures fails or becomes ineffective

What tasks can be taken to ensure that the control is working?

- Project engineering, operation, maintenance, management.

"How can we ensure that these tasks are done?"

"Who do these tasks?

"How do you know when to do the tasks?"?

"How do you know what to do?“"Is there a procedure, checklist, instruction?"


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Bow-tie Example

Unsafescaffolding Scaffoldingassemblystandards

Working at height

ContractorInspection

Safety DeptInspection

PPEcorrect use

Workersawarenessinduction

First AidsTeam

Injuries

Workers

Falling

Ladder

inadequateuse

Ladder

usesstandards

Contractor

Inspection

Safety Dept

Inspection

Mobileplatformdefective

Pre-useInspection

MaintenanceSupervision

Safety DeptInspection

PPEcorrect use

Workersawarenessinduction

EmergencyPlan

Fatality

Critical Safety Tasks


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Safeguarding life, property

and the environment

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0910 Bow Tie Risk Paulo Rheinbolt