Nuclear Regulation: Purpose, Philosophy, Principles, Processes and Values - A View

By Mike Weightman

Contents

• What is the Purpose of Nuclear Regulation?

• What is risk and safety?

• What is the underlying Philosophy of nuclear regulation?

• What are the Principles?

• What are the Processes?

• How do you “regulate” Safety Cultures”?

• Can it operate successfully in isolation to other parts of the Nuclear

System?

• What are its underpinning Values?

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Nuclear Regulation - Purpose

To secure the protection of people, society and the

environment from the risks (hazards) of the nuclear

industry

(allowing society the option to realise the benefits)

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What is Risk and Safety?

• Risk – chance of bad consequences, loss

• Safety – Freedom from Risks

• No such thing as absolute safety or zero risk

• Living is risky

• We tolerate risks to achieve benefits

• Some examples …

4

Examples of Risk: Chance of Death in UK Population

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Occupational exposure limit 20 mSv/y

Public exposure limit 1 mSv/y

Risk from radiation exposure – 0,05 chance of fatal

cancer per SV

(7)

Exposure to Ionising Radiation: Units of Dose (mSv/yr)

7

Nuclear Safety: risks of accidents

- Fukushima 2011

Tsunami following an earthquake

level 9.0 – direct impact: killed

around 20,000 people

Fukushima Dai-ichi

Estimated releases ≈ 10% of

Chernobyl

Effective evacuation

160,000 people evacuated

30 workers with doses > 100 mSv

Limited health consequences from

radiation (WHO, 2013)

But very heavy economic, social

and environmental

consequences

Nuclear Regulation:

A Philosophy

• Justification of activities of nuclear industry -

Government

• Limitation on risks incurred

• Optimisation - Reduce risks further by

application of ALARA(or ALARP) towards safety

goals – ensuring a culture of continuous

improvement (foundation stone of safety culture)

• 0

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A Risk Framework for Nuclear Regulation in the UK

Basic Safety Level

Basic Safety Objective

ALARP – Reduce the risks until

the costs in time, trouble and

expense is grossly

disproportionate

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Nuclear Safety: Continuous Improvement

Risk = event frequency × consequences.

Reduction in design estimate of the large release frequency between

reactor generations over the past five decades.

IAEA, 2004 (8)

Nuclear Regulation: Principles

• Independence

• Proportionality

• Objectivity, rationality, science/technical based with highest

technical competence

• Consistency

• Openness and transparency: communicating with all

stakeholders, a duty – listening, explaining in context, being

proactive

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Independence:

• - Structural

• - Financial

• - Cultural

Nuclear Regulation: Processes

• Setting principles/standards, guidance, regulations

• Assessing safety/security/safeguards cases/arrangements

• Permissioning activities

• Inspecting

• Enforcing

• Influencing people and organisations: safety culture

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Why is Influencing Safety Culture of Nuclear Industry so vital?

Regulatory

Leverage

Events

Patterns

Systems

Mind map

Vision

Plant/ Operations

Processes

Organisational Structures

Safety Cultures

Regulate Influence

Organisational

Learning

Reality &

Compliance Public Confidence

Regulators influence safety culture for better or worse, whether they intend to or not and it can have far greater impact – need to with others.

X 10000

X 1000 X100 X 10 X 1

Impac

t

Safety Culture

• Simply .... “its what people do when you are

not there”

• Cannot legislate for it

• But ... Regulators influence it in the nuclear

industry for better, or worse

• Its how you go about your regulation that

matters – obtaining the skills is essential – high

technical, communication and behavioural skills

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Nuclear Regulators:

the Crucial Part of a Nuclear System

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Technical Assurance of nuclear power

plant safety is not enough

• 3 Safety Functions: Contain, Control, Cool

• Contain the radiation

• Control the nuclear and chemical reactions

• Cool the fuel

• Multiple barriers (defence in depth) to stop failure of the Safety

Functions

• Diversity, redundancy, segregation of barriers/safety systems

• No single point failure

• Identify hazards, initiating events to realise them and failure paths

• Demonstrate through deterministic and probabilistic Safety Case

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Technical Defence In Depth - Generally Described

in Five Levels

Level of

defence in

depth

Plant Status Objective Essential Means

Level 1 Normal Operation Prevention of abnormal operation and

failures by design

Conservative design, construction,

maintenance and operation in accordance

with appropriate safety margins, engineering

practices and quality levels

Level 2 Operational

Occurrences

Control of abnormal operation and

detection of failures

Control, limiting and protection systems and

other surveillance features

Level 3 Accidents Control of accidents within the

design basis

Engineered safety features and accident

procedures

Level 4 Beyond Design Base

Accidents e.g. core

melt accident

Control of severe plant conditions in which

the design basis may be exceeded,

including the prevention of fault

progression and mitigation of the

consequences of severe accidents

Additional measures and procedures to

prevent or mitigate fault progression and for

on-site emergency management

Level 5 Significant off site

release of

radioactivity

Mitigation of radiological

consequences of significant releases of

radioactive materials

Emergency management and on-site and

off-site emergency response

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Technical Defence In Depth –

Fukushima: Common Mode Failure

Level of

defence in

depth

Plant Status Objective Essential Means

Level 1 Normal Operation Prevention of abnormal operation and

failures by design

Conservative design, construction,

maintenance and operation in accordance

with appropriate safety margins, engineering

practices and quality levels

Level 2 Operational

Occurrences

Control of abnormal operation and

detection of failures

Control, limiting and protection systems and

other surveillance features

Level 3 Accidents Control of accidents within the

design basis

Engineered safety features and accident

procedures

Level 4 Beyond Design Base

Accidents e.g. core

melt accident

Control of severe plant conditions in which

the design basis may be exceeded,

including the prevention of fault

progression and mitigation of the

consequences of severe accidents

Additional measures and procedures to

prevent or mitigate fault progression and for

on-site emergency management

Level 5 Significant off site

release of

radioactivity

Mitigation of radiological

consequences of significant releases of

radioactive materials

Emergency management and on-site and

off-site emergency response

Fukushima lesson: technical DID can be

subject to common mode failure through

Nuclear System Failure:

Need Strong Nuclear System Defence in Depth:

• Institutional Multiple and Diverse Independent Barriers

• Underpinned by safety culture of Continuous

Improvement - , never complacent, open reporting,

safety first; and compatible values

Nuclear Regulation as one part of the institutional

defence in depth system

A. Strong competent self regulating Industry

B. Strong Regulator

C. Strong competent Stakeholders

- Each barrier is Independent and has Sub-barriers within it

- Industry and the Regulator have to:

• have openness, transparency and accountability as a way of

life

• have an underpinning strong vibrant safety culture and

nuclear values

• welcome challenge with passion to improve

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Components of the Nuclear Industry Barrier in a State or Region

I.1 I.2 I.3 I.4

Licensee State/Region Industry Peer Pressure

International Industry Peer Pressure/Review

International Institutional Review

SQEP Technical/Design/operational capability

Safety Directors Forum, INPO, etc.

WANO Missions and Requirements

IAEA OSART Missions

Independent Nuclear Safety Assessment

Nuclear Industry Association, Nuclear Energy Institute, ANS

Bilateral/Multilateral Organisations e.g. CANDU Owners Group

Nuclear Safety Committee

Nuclear Leadership/Culture/Values 22

Components of a Strong Institution Regulatory Barrier

R.1 R.2 R.3 R.4

Regulatory Authority Special Outside Technical Advice

International Peer Pressure

International Peer Reviews

World Class Technical/Regulatory Capability

E.g. Standing Panel of experts nominated by stakeholders – CNI Advisory Panel/ Groupe Permanent d’ Experts

NEA CNRA & CSNI committees and working groups

IAEA IRRS missions

Organisational Structure with internal standards, assurance, OEF, policy, strategy, etc.

Special Expert Topic Groups - Fukushima - Aircraft Crash

WENRA – reference levels, reviews, groups

ENSREG Reviews

INRA – top regulators

Accountability to Governing Body – Board, Commission, etc.

IAEA Safety Standard meetings, etc.

Nuclear Leadership/Culture/Values 23

Components of the Strong Stakeholder Institutional Barrier

S.1 S.2 S.3 S.4 S.5 S.6 S.7

Workers Public Parliament National & Local

Gov.

Neighbours

Media NGOs

Industry and Regulatory Routine Supply of Information

Routine Reports on Activities and Decisions

Special Reports on Matters of Interest

Responsiveness to Requests for Information

Routine and Special Meetings

Openness & Transparency, Accountability, Assurance – Industry/Regulator Culture and Capability 24

Nuclear Regulators:

Some Values?

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Nurturing a culture of Welcoming Challenge and

seeking to Listen, Learn and Improve

Loss of Swedish Vasa Warship in 1628 in first 2km of maiden voyage – fear of telling the King that top heavy and need to delay

Strong: not about brute strength or power but Inner

Strength, Strategy and Skills

David and Goliath

Objectivity: Decisions based on rationality, facts,

knowledge and experience

Newton

Responsive: to survive and prosper it’s not the biggest but

the one who best responds to their changing environment

Darwin

Great Resilience: around a clear vision and strategy

Mandela

Integrity

Summary:

Your Regulatory Leadership is Vital

- Live the Nuclear Regulatory Values

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