experiences with goal based standards – relevance to...

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Experiences with goal based standards –relevance to shipping

Rolf Skjong, [email protected]

Chief Scientist, Risk & ReliabilityDet Norske Veritas

EMSA, Brussels, October 26, 2004

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Pick a regulatory ideology

Goal Based Regulation (e.g. UK MoD)goal Oriented Regulation (e.g. Canadian NEB),industrial self regulation regime (Norwegian offshore),safety Case Regime (UK HSE),risk informed, performance based (US NRC),performance based regulation,science based regulation (US Food and Drug Administration),result based regulation (Canada/BC deregulation office), etc.

A large activity in regulatory reformSome studies on efficiency of regulations (OECD, Institutes of regulatory reform)It is worth looking into experiences from other industry

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NEB comparing Regulatory Styles

self auditcompany determined

outcomesSelf regulation

objective criteria

risk-basedmeasuresPerformance-based

professional judgement and acceptance criteria

risk-informedgoalsGoal-oriented

check listdeterministicmeansPrescriptive

ComplianceRisk approachDefinesRegulatory style

Comparison of Regulatory Styles[1]

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Why Goal Based Regulation?

Standard arguments/literature:Transparency: Is the regulation justified from

SafetyEnvironmental Standardisation (practical, inter-modal, interoperability)

Opens for free competition and innovationAccommodate different standards:

Goal Based Standards not Standard!

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Why Goal Based Regulation?Result of need for transparency and justification for regulations.

Reaction to prescriptive regulations which:

i. ..tend to put the responsibility on the regulator if a solution proves insufficient to prevent an accident. The service provider only follows prescription and is thereby feeling relieved of responsibility

ii. ..are distilled from past experience. When technology are developing fasten than experience can be gained the regulation may become a direct threat to safety.

iii. …encourage mediocrity and are destructive for innovation.

iv. …are used as trade barriers and may be viewed as illegal in the context of free trade agreements (e.g WTO, EU)

From ‘Danish +’ submission

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Relationship between safety goals and functional requirements

Optional sub systems and components

Detailed rule requirements

Major systems and equipment

Main ship functions

Overall objectives

Func

tiona

l Req

uire

men

tsG

oals

Rul

esIM

OC

lass

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Goal Based Regulation

Wishes and perceptions (IMO submissions)

State what shall be achieved

No method on how to achieve

Open for innovation

Ensure against sub-standard

Clear

Demonstrable

Long standing

Adaptable

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Risk Based Regulation - FSA

StructuredSystematicComprehensiveObjectiveRationalAuditable

RepeatableWell documentedDefensibleReliableRobust

Wishes and perceptions (UK/1997)

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Example Goal Based Regulation?

‘People shall be prevented from falling over board’Example of Prescriptive Regulation ‘Ships shall have a 1 meter high railing surrounding each deck and open space where people could otherwise fall over board’IMO, after accident where a crew member is washed overboard though the railing ‘Ships shall have a 1 meter high railing, with a maximum distance between horizontal rails of 10 cm, surrounding each deck and open space where people could otherwise fall over board’Etc. New accident – more detailed prescription

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Challenge with Goal Based Regulation?

High Level Goals are more abstract (e.g. 10-4

probability/ship year) than prescriptive regulation (1 meter high)Goal Based Regulations require higher level of training, in order to result in same practiceVerification will be on abstract level: What is a credible argument for safety? Some have introduced the concept of Assurance Evidence Level (AEL) – and software tools are available.Goal Based Regulations must deter from presenting untenable argumentsGoal Based Regulations relating to safety and environmental regulations are also risk based

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Goal in Goal Based Regulation?

Example of high level goal in use (safety):Risk should be ‘tolerable and ALARP’Goal based regulations can be applied at any level, from top-level systems (the ship) downwards Need a method to break down high level goals to tenable sub-goals:This method is QRA/PSA/FSA

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Goal – High Level Goal? Proposed:

design life,

environmental condition,

structural safety,

structural accessibility,

quality of construction

Of these: Only one high level goal

In submissions a number of other goals is mentioned.

Most are on the level already in e.g. SOLAS

Evacuation in 30 minutes, 60 minutes fire protection, 40 meter fires zones etc.

On this level of abstraction the number of goals are countless

This is clearly not the intention!

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Fatigue – Risk Based• SN-curve for new component )(log)(log)(log SmKN ⋅−=

• Experience from similar components :

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Deterministic vs. Probabilistic Approach

Critical crack size

Initi

al d

efec

t siz

e Deterministic crack growth

Probabilistic crack growth

Time until critical crack

Time

Cra

ck si

zea

2c

MP

t

P

M t

2c

a crack

Life time

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Fatigue Analysis MethodsS-N Fatigue Assessment

S S

Structural detail

weldPotential

Crack growth• S-N data - experimental data

S-N DATA

1.80

1.90

2.00

2.10

2.20

2.30

2.40

2.50

2.60

2.70

2.80

4.5 5.0 5.5 6.0 6.5 7.0 7.5Log(N)

Log(

S)

S-N data

S-N DATA & S-N Curve

1.80

1.90

2.00

2.10

2.20

2.30

2.40

2.50

2.60

2.70

2.80

4.5 5.0 5.5 6.0 6.5 7.0 7.5Log(N)

Log(

S)

S-N data

S-N curve - Fit

S-N DATA & S-N Curve

1.80

1.90

2.00

2.10

2.20

2.30

2.40

2.50

2.60

2.70

2.80

4.5 5.0 5.5 6.0 6.5 7.0 7.5Log(N)

Log(

S)

S-N dataS-N curve - FitDesign S-N curve (mean-2*StD)

µLogN

µLogN − 2 σLogN

Log(N) = Log(ā) - m · Log S - 2 σLogN

• S-N Design Curve:

• S-N Mean Curve:Log(N) = Log(ā) - m · Log(S)

N = ā · S-m

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Integrated Fatigue analysis -Uncertainties

Environmental description

Load And Response analysis

Detailed Stress analysis (SCF)

Fatigue analysis

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Specify Design Life?

This should be specified by IMO

This should beS

pecified by owner

Design life

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High Level Goal – Tradition (NKB/DNV/ISO/CEN)

Calibration against well established codes that are judged acceptable or best practices for the same type of structuresCalibration against well established codes that are judged acceptable or best practices for similar type of structuresCalibration against tabulated values, using distribution assumptions that are judged to be (slightly) conservative

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PF = 10-6, βT = 4.75PF = 10-5, βT = 4.26III - No warning before the occurrence of failure in a non-redundant structure

PF = 10-5, βT = 4.26PF = 10-4, βT = 3.71II - Significant warning before the occurrence of failure in a non-redundant structure

PF = 10-4, βT = 3.71PF = 10-3, βT = 3.09I- Redundant Structure

SeriousLess serious

Consequence of FailureClass of Failure

Table 1: Annual Target Probabilities (and Target βT) from DNV Classification Note 30.6

High Level Goal – Tradition (NKB/DNV/ISO/CEN)

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Goal – High Level Goal?

We have some goal based standards

SOLAS II-2, Reg 17

New damage stability regulation (A<R)

Is this a relevant model?

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Justification for Regulating - Goals

Method of analysis

Issues needing regulations – Distributed Goals

Goal Based Standards

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Safety Environment Security Interfacing

Fire Protection

Nav. Safety Freeboard Opera

-tional LSADamaged Strength

Intact Strength Systems

Accident Scenarios

RulesStructure

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IMO Subcommittee Structure

R = Pc x Pi|c x Ps|i|c x Pf|s|i|cx Pr|f|s|i|c x N

NAV

DE SLF

FP

NAV = Navigation Sub-committeeDE = Design and Equipment (Strength Issues)SLF = Stability Load Lines and Fishing Vessels FP = Fire Protection (dealing with evacuation)COMSAR = Communication, search and rescue

COMSAR

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Goal Based Regulation –Trivial Version

Fire Protection

Nav. Safety

Freeboard

Opera-tional

LSA

Damaged Strength

Intact Strength

Systems

High Level Goals?A > R

Damage Stability

Ai > Ri

Ai > RiAi > Ri

Ai > Ri

Ai > Ri

Ai > Ri Ai > Ri

Ai > Ri

∑Ri=R

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ConclusionsSome experience with GBR in other industries is worth studying

For structures a well developed technique exists

The proposed regime is probably ‘goal based risk informed’

The relation between ‘goal based’ and ‘risk informed’ is as between style and method

Uniform interpretation is a challenge

Training is necessary

SAFEDOR.ppt

SAFEDOR: CAR, DMA, DNV, GL, ITF, IZAR, SAM, SSRC Page 1 Safety through Innovation

WHAT IS SAFEDOR ?

Planned Integrated Project within the current R&D-Framework Programme of the European Commission

In response to a call on

– Thematic priority “Sustainable Surface Transport”

– Topic “Risk based ship design and approval”

Current status

– Contract negotiations ongoing

– Planned start in early 2005, duration 4 years


SAFEDOR STEERING COMMITTEE

Owner Carnival plc (United Kingdom)

Yard IZAR (Spain)

Manufacturer SAM Electronics (Germany)

Flag State Danish Maritime Authority (Denmark)

Class Society DNV (Norway)

Seafarers ITF (International)

University Glasgow and Strathclyde (United Kingdom)

Class Society (Chair) GL (Germany)


THE VISION OF SAFEDOR

ENHANCE SAFETY THROUGH INNOVATION

TO STRENGTHEN THE COMPETITIVENESS

OF THE EUROPEAN MARITIME INDUSTRY


THE MISSION OF SAFEDOR

Provide solutions for two key issues of the European maritime industry

– Increase the safety and security of waterborne transport cost-effectively by treating safety as design objective

– Increase the competitiveness of European industry by systematic innovation in design and operations and by modernizing the regulatory system


APPROACH TO INCREASE COMPETITIVENESS OF EUROEPAN MARITIME INDUSTRY

Remove rule-based constraints to innovative design solutions (through providing an alternative regulatory framework)

Focus on knowledge-intensive and safety-critical vessels with high economic value for Europe

Offer support to apply new methodology through funding of a series of specific applications for selected ship types


THE OBJECTIVES OF SAFEDOR

Develop methods and tools to assess operational, extreme, accidental and catastrophic scenarios, accounting for the human element, and integrate these into a design environment

Develop innovative technologies for safety-critical equipment to support safe, secure and economic operation of ships

Establish a risk-based regulatory framework to facilitate first principles approaches to safety

Produce prototype designs for European safety-critical vessels to validate the proposed methodology and demonstrate its practicability


SUMMARY OF SAFDOR ACTIVITIES

WP 1: project management

WP 2: design tools for safety performance prediction

WP 3: innovative technologies for safety-critical equipment

WP 4: risk-based regulatory framework

WP 5: risk-based design integration

WP 6: validation and implementation for innovative ship designs

WP 7: training and dissemination


SAFEDOR PARTNERSHIP

Ship operator

Equipment manufacturer

ShipbuilderEngineering consultant

Software manufacturer

University department

Research institute

Training facility

Classification society

Government agency

Based on number of partners


NEXT STEPS

Expected start of project SAFEDOR in early 2005

Visit www.safedor.org

http://www.safedor.org/

experiences with goal based standards – relevance to...

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