Download - Title slide PIPELINE QRA SEMINAR. PIPELINE RISK ASSESSMENT RISK ACCEPTANCE CRITERION 2

PIPELINE QRA SEMINAR

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PIPELINE RISK ASSESSMENTRISK ACCEPTANCE CRITERION

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“comparing the level of risk found during the analysis

process with risk criteria established”

INTRODUCTION TO RISK ACCEPTANCE CRITERION

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• Why do you have a risk acceptance criterion?

• End-point of the risk assessment

• To be able to say whether the risk is acceptable or not

• Established by companies (internal) and/or authorities

(external)

• Base for decision-making


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• Usually talking about:

- Tolerable (acceptable - green)

- Intolerable (unacceptable - red)

• And then…

- ALARP (control to ALARP/acceptable if ALARP - yellow)

• What is ALARP?


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• Two conflicting objectives need to be balanced

-We have a desire to do everything physically possible to

remove all risks

- We have limited resources and that it is nearly always not

practical (nor physically possible) to remove all risk

• ALARP principle include demonstrate that the cost

involved in reducing the risk further would be grossly

disproportionate to the benefit gained


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• When is a risk tolerable (acceptable)?

• What is a risk intolerable (unacceptable)?


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• Everyday life – risk perception deciding the risk acceptance

criterion

Definition (Wikipedia)

“the subjective judgment that people make about the

characteristics and severity of a risk”

• 19 per 100.000 deaths from driving

• < 0.5 per 100.000 deaths from flying

• 268 per 100.000 deaths from cardiovascular diseases


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• Risk perception could be depending on a number of factors:

- Social context (e.g. group pressure)

- Benefits versus losses (i.e. what could be gained versus lost)

- Risk aversion (i.e. better many small accidents than one

catastrophe)

- Control (e.g. driver versus passenger)

- Experience (i.e. unknown or know)

• Driving versus flying


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• Working life – different theoretical approaches on how to

decide the risk acceptance criterion

- Comparison (e.g. statistics on accidents/fatalities and

other industries/activities)

- State-of-the-art (i.e. as safe as possible)

- Economics (i.e. price per human life)

• Different for organizations (e.g. the well being for many)

versus companies (e.g. economical aspects) versus

authorities (e.g. combinations)


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• Traffic authorithy in Sweden state that 22.3 million SEK

(5.5 million GEL) is the acceptable cost for saving a life

• Safety systems (e.g. traffic barrier) is analyzed with this

approach

• How many lives could we save with this implementation

of safety system – comparison with total cost and the

acceptable cost for saving a lie (or several lives)

EXAMPLE OF RISK ACCEPTANCE CRITERION – SWEDEN TRAFFIC AUTHORITY

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• Traffic authority in Norway state that 25.0 million NOK

(5.5 million GEL) is the acceptable cost for saving a life

• Offshore industry in Norway state that up to 100.0

million NOK (up to 27.3 million GEL) is the acceptable

cost for saving a life

EXAMPLE OF RISK ACCEPTANCE CRITERION – SWEDEN TRAFFIC AUTHORITY

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• What kind of risk acceptance criterions are there?

• Quantitative and qualitative (compare with quantitative risk assessment and qualitative risk assessment)

• You can have risk acceptance criteria for everything!

-Environmental

-Human safety (e.g. discomfort, injuries and fatalities)

-Economical

-Project (e.g. delay)

-Reputation


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-Environmental (e.g. allowable size of release and impact on the

environment)

-Human safety – individual risk (i.e. allowable risk for a single person)

- Human safety – group risk/societal risk (i.e. allowable risk for a defined

population)

- Human safety – consequence distance (e.g. allowable for dispersion of

gas)

-Economical (e.g. allowable potential loss from investment and cost)

-Project (e.g. allowable delay)

-Reputation (e.g. allowable attention from news, NGO’s and authorities)


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• Current risk acceptance criteria - consequence distance of

200 meters (no activities or structures)

• Difference between consequence distance of 200 meters

(fixed) and consequence distance of X meters (based on

calculations of allowable concentrations)

• Paper product versus actually practical (e.g. pipelines in

urban areas and supply of gas to industries/residences)

EXAMPLE OF RISK ACCEPTANCE CRITERION – GEORGIA PIPELINES

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• Future risk acceptance criteria – human safety based (e.g.

individual risk/societal risk)

• What could be the benefits?

- Flexibility - allow activities and structures within 200 meters

(sometimes not!)

- Actual knowledge and understand of the risk from the pipeline

EXAMPLE OF RISK ACCEPTANCE CRITERION – GEORGIA PIPELINES

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• Qualitative risk acceptance criteria

- Risk matrix

- Descriptions

• Descriptions support to the risk matrix

• Descriptions

- Human safety (e.g. minor injury or health effect or multiple

fatalities)

- Environmental (e.g. major environmental damage over an

extensive area, but recovery is possible)

- Reputation (e.g. National public, government or NGO concern)

QUALITATIVE RISK ACCEPTANCE CRITERION

Probability/frequency

HighMedium

LowLow Medium High

Consequence

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QUALITATIVE RISK ACCEPTANCE CRITERION


HighLow

Low High

Consequence


SevereSignificantModerate

MinorNegligible

Very unlikely

Unlikely Possible LikelyVery likely

Consequence Probability/frequency

HighMedium

LowLow Medium High

Consequence

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QUALITATIVE RISK ACCEPTANCE CRITERIONProbability/frequency

HighMedium

LowFatalities Injuries Discomfort

ConsequenceProbability/frequency

HighMedium

Low

Massive environmental

impact (no recovery)

Massive environmental

impact (recovery)

Small environmental impact (recovery)

Consequence

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• Quantitative risk acceptance criteria

- Numerical values (more or less)

• Human safety - individual risk

- individual risk for 1st person (e.g. operator)

- individual risk for 3rd person (e.g. public)

QUANTITATIVE RISK ACCEPTANCE CRITERION

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• Human safety – group risk/societal risk

- group risk/societal risk for 1st person and 3rd person

(including the entire population)

• Presented as FN-curve

- Frequency plotted against the number of fatalities

- Cumulative frequency of N or more fatalities

- Criteria 1 – 1 fatality with frequency 1 x 10-3 per year

- Criteria 2 – 10 fatalities with frequency 1 x 10-5 per year


• Offshore also presented as FAR (Fatal Accident Rate)

- Fatalities per 0.1 billion (108) working hours (or exposure hours)


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• FN-curve

- Frequency plotted against the number of fatalities

- Cumulative frequency of N or more fatalities

- Criteria 1 – 1 fatality with frequency 1 x 10-3 per year



- Accident 1 – 100 fatalities with frequency < 1 x 10-9 per year

- Accident 2 – 10 fatalities with frequency 4 x 10-7 per year

- Accident 3 – 1 fatality with frequency 1 x 10-5 per year

- Accident 4 - …


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• Who is deciding the risk acceptance criterion?

• Established by organizations (guidelines), authorities

(legal requirements) and companies (internal

requirements)

• Different theoretical approaches for organizations (e.g.

the well being for many) versus companies (e.g.

economical aspects) versus authorities (e.g.

combinations)


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• Comparison of different quantitative risk acceptance criterion for individual risk:

- U.K. – 3rd party – acceptable at < 1.0 x 10-6 per year

- Netherlands – 3rd party - acceptable at < 1.0 x 10-8 per year

- Netherlands – 3rd party - unacceptable at > 1.0 x 10-6 per year (for new facilities)

- Netherlands – 3rd party - unacceptable at > 1.0 x 10-5 per year (for existing facilities)

- Venezuela – 1st party – acceptable at < 1.0 x 10-6 per year

- Venezuela – 1st party – unacceptable at > 1.0 x 10-3 per year


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• Comparison of different activities and quantitative risk acceptance criterion for individual risk

(usually < 1.0 x 10-6 per year):

- dying (non-specific cause) - 1.0 x 10-2 per year

- smoking (20 cigarettes per day) – 5 x 10-3 per year

- 1.0 x 10-6 per year

- killed by lightning - 1.0 x 10-7 per year

- killed by meteorite - 1.0 x 10-11 per year


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• Comparison of different quantitative risk acceptance

criterion for group risk/societal risk

- Dark blue – Flanders (region in Netherlands)

- Blue – Netherlands

- Pink – Denmark (where grey indicate ALARP)

- Red – indicative value for U.K.


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• Comparison of different activities and quantitative risk acceptance criterion for group risk/societal risk

(usually FAR = 15 – fatalities per 108 working/exposure hours):

- staying at home - 3

- agriculture – 3.7

- 15

- driving a car - 57

- driving a motorcycle - 660


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QUESTIONS?

Download - Title slide PIPELINE QRA SEMINAR. PIPELINE RISK ASSESSMENT RISK ACCEPTANCE CRITERION 2

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