Sunday, March 29, 2015

Nuclear Safety Assessment Principles in the United Kingdom

A reader sent us a copy of “Safety Assessment Principles for Nuclear Facilities” (SAPs) published by the United Kingdom’s Office for Nuclear Regulation (ONR).*  For documents like this, we usually jump right to the treatment of safety culture (SC).  However, in this case we were impressed with the document’s accessibility, organization and integrated (or holistic) approach so we want to provide a more general review.

ONR uses the SAPs during technical assessments of nuclear licensees’ safety submissions.  The total documentation package developed by a licensee to demonstrate high standards of nuclear safety is called the “safety case.”


The language is clear and intended for newbies as well as those already inside the nuclear tent.  For example, “The SAPs contain principles and guidance.  The principles form the underlying basis for regulatory judgements made by inspectors, and the guidance associated with the principles provides either further explanation of a principle, or their interpretation in actual applications and the measures against which judgements can be made.” (p. 11) 

Also furthering ease of use, the document is not strewn with acronyms.  As a consequence, one doesn’t have to sit with glossary in hand just to read the text.


ONR presents eight fundamental principles including responsibility for safety, limitation of risks to individuals and emergency planning.  We’ll focus on another fundamental principle, Leadership and Management (L&M) because (a) L&M activities create the context and momentum for a positive SC and (b) it illustrates holistic thinking.

L&M is comprised of four subordinate (but still high-level) inter-related principles: leadership, capable organization, decision making and learning.  “Because of their inter-connected nature there is some overlap between the principles. They should therefore be considered as a whole and an integrated approach will be necessary for their delivery.” (p. 18)

Drilling down further, the guidance for leadership includes many familiar attributes.  We want to acknowledge attributes we have been emphasizing on Safetymatters or reflect new thoughts.  Specifically, leaders must recognize and resolve conflict between safety and other goals, ensure that the reward systems promote the identification and management of risk, encourage safe behavior and discourage unsafe behavior or complacency; and establish a common purpose and collective social responsibility for safety. (p.19) 

Decision making (another Safetymatters hot button issue) receives a good treatment.  Topics covered include explicit recognition of goal conflict; appreciating the potential for error, uncertainty and the unexpected; and the essential functions of active challenges and a questioning attitude.

We do have one bone to pick under L&M: we would like to see words to the effect that safety performance and SC should be significant components of the senior management reward system.

Useful Points

Helpful nuggets pop up throughout the text.  A few examples follow.

“The process of analysing safety requires creativity, where people can envisage the variety of routes by which radiological risks can arise from the technology. . . . Safety is achieved when the people and physical systems together reliably control the radiological hazards inherent in the technology. Therefore the organizational systems (ie interactions between people) are just as important as the physical systems, . . . “ (pp. 25-26)

“[D]esigners and/or dutyholders may wish to put forward safety cases that differ from [SAP] expectations.   As in the past, ONR inspectors should consider such submissions on their individual merits. . . . ONR will need to be assured that such cases demonstrate equivalence to the outcomes associated with the use of the principles here,. . .” (p. 14)  The unstated principle here is equifinality; in more colorful words, there is more than one way to skin a cat.

There are echoes of other lessons we’ve been preaching on Safetymatters.  For example “The principle of continuous improvement is central to achieving sustained high standards of nuclear safety. . . . Seeking and applying lessons learned from events, new knowledge and experience, both nationally and internationally, must be a fundamental feature of the safety culture of the nuclear industry.” (p. 13)

And, in a nod to Nicholas Taleb, if a “hazard is particularly high, or knowledge of the risk is very uncertain, ONR may choose to concentrate primarily on the hazard.” (p. 8)

Our Perspective

Most of the content of the SAPs will be familiar to Safetymatters readers.  We suggest you skim the first 23 pages of the document covering introductory material and Leadership & Management.  SAPs is an excellent example of a regulator actually trying to provide useful information and guidance to current and would-be licensees and is far better than the simple-minded laundry lists promulgated by IAEA.

*  Office for Nuclear Regulation, “Safety Assessment Principles for Nuclear Facilities” Rev. 0 (2014).  We are grateful to Bill Mullins for forwarding this document to us.


  1. Does the UK actually live by this or is it another instance of "Britannia waves the rules?"

    1. I have no idea if they "live by it" or not. What I think is going on here is that ONR is trying to present itself as a kinder, gentler regulator to encourage firms working on small modular reactors (SMRs) to step up to the wicket and submit their designs for approval.

  2. Having been to the UK and observed their nuclear regulatory scheme in action I would report that this is how it actually functions - Safety Case with Duty of Care accountability is a different strategy and approach on the evidence.


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