operational Safety
License to Operate from regulator dependent on meeting license conditions (LCs)
Outline
Operational nuclear safety
Focus on nuclear safety and underlying cultural issues
safety systems and processes (but not safety cases)
Example License Condition requirements
Operating experience feedback (LC 7)
Operating rules (LC 23)
Management of change (LC 36)
Behavioural interventions to improve performance
Overall safety management system
Operational Nuclear Safety
Remaining within the limits of the safety case
Procedures, monitoring, analysis and learning processes
Suitably qualified, experienced and competent staff
Good management
Good safety culture
the right things are done with the right attitude so as to achieve the right results
Reason’s Swiss Cheese Model
Defence in depth (many layers)
Works most of the time
All have weaknesses
Can line up with disastrous results
Culture is fundamental
The culture determines the quality of the safety management processes
How big the holes in the cheese are
How they are monitored and reduced
Helps ensure they are not aligned
Generic problem
Generic problem
Findings
High proportion (by far) of events attributed to human factors
Top four root causes:
Personnel work practices
Procedures
Verbal communications
Supervisory methods
Event investigations
Often don’t ask ‘why’ enough
Its easiest to focus on the individual
……but this won’t help to move things forward and prevent future events
Key is know why the individuals behaved as they did – what are the human factors?
Human Factors in events
The learning loop
Closing the learning loop
‘To look is one thing,
To see what you look at is another.
To understand what you see is another.
To learn from what you understand is something else.
But to act on what you learn is all that really matters.’
Sir Winston Churchill
Review findings
Rules were sometimes
not clearly written (poor language, over complex)
contained no operational margin
were not relevant to nuclear safety
Rules “invited” the operators to breach them
Guidance was needed for rewriting the Rules
Guiding Principles
P3
The operating limits set out in the rules should be such that a breach represents a significant erosion of safety, commensurate with the external attention it attracts
P10
A clear identification is required of which rules are appropriate to normal steady state conditions and which to other situations (including faults, start-up, post-trip and shut-down situations).
P11
Rules should (so far as is practicable) refer only to plant parameters and conditions which can be directly monitored (and preferably be directly controlled) by the station staff.
P12
Rules should not require staff to process information presented to them unless the appropriate support is provided.
P15
Rules should use derived operating limits which anticipate faults, rather than basic safety limits.
Outcome
Many principles concerned with making the Rules easier to follow and comply with i.e. making the operators’ job easier
Programme of Rule revision
Very significant reduction in Rule breaches
Measurable benefit
Outcome
Many principles concerned with making the Rules easier to follow and comply with i.e. making the operators’ job easier
Programme of Rule revision
Very significant reduction in Rule breaches
Greater credibility of Rules
Greater regulator and public confidence
Greater self awareness and self confidence
Management of Change
Newest License Condition (LC36)
Introduced to address the increasing instability in UK Nuclear Industry since 1989
Restructuring, privatisation, downsizing, re-organisation (local and corporate), contractorisation, competition
Loss of experience, uncertainty (role, job security)
Requires formal statement of how nuclear safety is ensured during and after the change
Key performance indicators to monitor the change
Weakness
Too formal/theoretical
Attitudes and morale not properly covered
Teamworking and loyalties
Influx of contractors
Loss of “latent” expertise
New management style
Clash of cultures
People are not components
Safety Management
Behavioural interventions
The sharp end