The nuclear option: human factors in safety Sue Cox Professor of Safety and Risk Management Dean Lancaster University Management School Blackett Memorial Lecture 14 th March 2006
Nuclear Power: a problem or the solution?
Can Safety Science help answer this question?
Current nuclear capacity (UK) NDA Sites British Energy Sites Source: http://www.nda.gov.uk Source: http://www.british-energy.co.uk
‘First Movers’ Berkeley, UK Calder Hall, UK Source: http://www.google.image.com
FAQ - New reactors
Why is nuclear back on the agenda? Due to alarm over climate change and the security of gas supplies. All but one of the existing nuclear stations will close by 2023 and ministers are anxious to ‘keep the lights on’.
So what’s stopping them? Fears over cost and issues of nuclear waste disposal.
What about safety? The nuclear sector says the new reactor designs are much safer.
How much would we pay for them? Fixed electricity prices, or so-called nuclear tax, is one option for the future.
What happens next? Separate strands of research are due to come together in time for a decision which is due summer 2006.
Source : The Guardian, 07.03.2006
TVO Olkiluoto 3, Finland As on 19 th January 2006 Source: http://www.tvo.fi/474.htm
The Safety Imperative
‘ Defence in depth ’ includes consideration of the following:
Preventing incidents and accidents by considering the potential for equipment failure, human error and external factors (for example seismic event, airplane crash, adverse weather conditions, etc) during the design phase - implementing effective systems and procedures
Monitoring facilities during operation to detect and correct deviations
Designing and implementing measures to limit consequences of any accidents that may occur despite the precautions taken.
Source: IAEA (1996) Defence-in-Depth in Nuclear Safety . A report by the International Nuclear Safety Advisory Group, INSAG-10, Vienna.
Nuclear Accidents Chernobyl, 1986 Three Mile Island, 1979 Source: http://www.google.image.com
Defence in Depth Human factors have been implicated in the aetiology of many nuclear (and non nuclear) accidents Source: IAEA (2003) Major Accident Summary. http://www.iaea.org/index.html Loss of Life Unacceptable release detectable in a number of European countries Contamination of a wide area Limited gaseous release - no consequences for the population Accident Consequences Satisfactory behaviour of third barrier Second barrier failure (later restored) Instantaneous and simultaneous loss of first and second barriers Design fault with third barrier (i.e. not designed to remain leak-tight in the event of an accident) First barrier failure Barrier Failures Loss of control of containment function Loss of control of reactivity function Loss of control of cooling function Loss of control of cooling function Safety Function Faults Chernobyl Three Mile Island
Human factors is a multidisciplinary activity concerned with peoples’ characteristics and capabilities in relation to the design of jobs, products, workplaces and equipment (Cox & Cox, 1996).
Hollnagel (1993) quotes figures which show a rise in human error rates from 25% of accident causation in the 1960s to 90% in the 1990s. He highlights the enhanced reliability of technology in part explanation.
Whatever the causation, the message is clear: managing the safety, reliability and efficiency of systems requires an understanding of human factors.
However, human factors, as traditionally conceived, is too narrow an approach to ‘people’ related issues in nuclear safety.
People-related Issues: Broader View Organisation Social Environment Job Person Wider Environments The Person as an Information Processor Developed from: Cox and Cox (1996) Safety, Systems and People. Oxford: Butterworth-Heinemann
Management of Change
What are the perceived emerging challenges in the management of nuclear power plants?
How do senior managers cope with emerging challenges in the management of nuclear power plants?
What improvements could be made in respect to coping with emerging challenges in the management of nuclear power plants?
What kind of features and attributes characterise learning organisations?
What are the most common barriers to organisational learning and how can they be removed?
How are various national and company cultures influencing organisational learning?
800 statements on ‘emerging challenges’ were collected from 300 managers in 10 power plants in 5 countries using a Metaplan method
Data subject to a 3 stage procedure derived from fuzzy set analysis:
Common classification model : 5 dimensions (derived from Competing Values Framework: Cameron and Quinn, 1999) treated as fuzzy sets
Classification of statements on ‘emerging challenges’ in terms of these sets: 0-100 strength of membership
Hierarchical cluster analysis : clustering coefficient showed a large increase from 9 to 10 clusters. K Means Method 1 used to create 9 clusters. Named on challenges close to centre of cluster.
Cross tabs by cluster, country and management level (Chi-square)
1 Tou JT and Gonzales RC. (1974). Pattern Recognition Principles . Reading, MA: Addison -Wesley. (pp. 94-97).
Key safety challenges for nuclear industry Source: http://www.vtt.fi/virtual/learnsafe/ - 101 100 100 100 99 TOTAL 4.6 4 3 3 8 5 9. Miscellaneous 19.2 27 8 24 16 21 8. Climate and culture 9.8 1 11 21 5 11 7. Public confidence and trust 11.0 12 9 3 13 18 6. Ageing, modernisation 10.8 16 11 3 8 16 5. Focus and priorities 5.6 7 6 8 5 2 4. Rules and regulation 7.8 4 11 8 11 5 3. Nuclear know-how 22.6 26 29 19 18 21 2. HR management 8.6 4 12 11 16 0 1. Economic pressures ALL UK SWE SP GER FIN CHALLENGE CLUSTERS
Culture and People Management
LearnSafe data show very clearly that ‘human resource management’ (22.6%) and ‘climate and culture’ (19.2%) are perceived by the industry to be the two most important challenges for nuclear safety going forward.
Other challenges range in perceived importance from 4.6% to 11.0% (‘ageing and modernisation).
LearnSafe also collected case study data on how managers were coping with these challenges through: safety culture change programmes, leadership training and staff development. .
Interaction of Culture and Behavioural Safety
There are two quite distinct approaches to promoting safety in high reliability industries: the top down organisational change approach and the bottom up individually focused approach
Today these are more enlightened and may manifest in:
Culture change (top down)
Behavioural safety programmes (bottom up)
Neither can fulfil its potential without the other and the key, going forward, is an integrative approach where individually focused behavioural safety programmes are supported and framed by strong leadership through organisational culture change.
A plethora of definitions exist that are relevant to the nuclear industry (for example: ACSNI and IAEA) and, associated with these, a wide array of measurement systems and tools
Some definitons (and studies) make a distinction between safety climate and safety culture: not always helpful in practice as most differences are based on methodological (research) considerations
There is an obvious value of explicative models in the development and application of measurement systems and tools and in the interpretation of the data collected using them (for example, Cheyne, Cox, Oliver and Tomas, 1998)
Modelling Safety Culture
ACSNI definition as a starting point:
‘ Safety culture is the product of individual and group values, perceptions, competencies and patterns of behaviour that determine the commitment to and the style and proficiency of an organisation’s health and safety management’ (HSC, 1993; p 23)
Research model derived from this definition. Study based on about 1,000 workers within a multinational manufacturing company. Questionnaire data subject to structural equation modelling (LISREL).
An Empirical Model of Safety Culture Workplace hazards Safety activities .796** .197* .720** .867** -.232** .284** .505** .450** .317** .102* -.266** .384** Source : Cheyne, A., Cox, S., Oliver, A. and Tomas, J. (1998) Work and Stress , 12, 255-271 Safety standards and goals Safety management Physical work environment Communication Personal involvement Individual responsibility
Behavioural Safety Process Review existing safety data Coaching and mentoring Feedback on an individual group and site wide level Make periodic observations of routine work tasks Modifications to environment, equipment or procedures Developed from : Cox, S., Jones, B., and Rycraft, H (2004) Safety Science, 42, 825-839 Organisational learning Management problem solving cycle
Difficult challenge to evaluate outcomes because of ceiling effect: safety measures are, by-and-large, in place and nuclear safety performance is good both in terms of releases and accidents: not able to experiment by withdrawing measures
Some evidence (next slide for example) that additional new measures, such as those described here, have effect
Emphasis therefore has to be on process based evaluation and compliance and involvement in new strategy
The 7 th Annual Report, produced by NuSAC in January 2006 reviews the safety performance of the nuclear industry to date considering a wide range of safety related measures.
It concludes that “ the substantial improvements (in safety) repoirted over the last decade for the Civil Licensees have been broadly maintained … At the Defence Sites, performance on dose management continues to show good results with no employee or contractor experiencing a dose in excess of 5 mSv. .. “
All measures of safety risk show low levels on all measures, for example: