Tuesday, September 24, 2013

Safety Paradigm Shift

We came across a provocative and persuasive presentation by Jean Pariès Dédale, "Why a Paradigm Shift Is Needed" from the IAEA Experts Meeting in May of this year.*  Many of the points resonate with our views on nuclear safety management; in particular complexity, the fallacy of the "predetermination envelope"- making a system more reliable within its design envelope but more susceptible outside that envelope; deterministic and probabilistic rationalization that avoids dealing with complexity of the system; and unknown-unknowns.  We also believe it will take a paradigm shift, however unlikely it may be at least in the U.S. nuclear industry.  Interestingly, Dédale does not appear to have a nuclear power background and develops his paradigm argument across multiple events and industries.

Dédale poses a very fundamental question: since the current safety construct has shown vulnerabilities to actual off-normal events should the response be, do more of the same but better and with more rigor? Or should the safety paradigm itself be challenged?  The key issue underlying the challenge to this construct is how to cope with complexity.  He means complexity in the same terms we have posted about numerous times.

Dédale notes “The uncertainty generated by the complexity of the system itself and by its environment is skirted through deterministic or probabilistic rationality.” (p. 8)  We agree.  Any review of condition reports and Tech Spec variances indicates a wholesale reliance on risk based rationale for deviations from nominal requirements.  And the risk based argument is almost always based on an estimated small probability of an event that would challenge safety, often enhanced by a relatively short exposure time frame.  As we highlighted in a prior post, Nick Taleb has long cautioned against making decisions based on assessments of probabilities, which he asserts we cannot know, versus consequences which are (sometimes uncomfortably) knowable.

How does this relate to safety management issues including culture?

We see a parallel between constructs for nuclear safety and safety culture.  The nuclear safety construct is constrained both in focus and evolution, heavily reliant on the design basis philosophy (what Dédale labels “predetermination fallacy”) dating back to the 1960s.  Little has changed over the succeeding 50 years; even the advent of PRA has been limited to “informing” the implementation of this approach.  Safety culture has emerged over the last 10+ years as an added regulatory emphasis though highly constrained in its manifestation as a policy statement.  (It is in fact still quite difficult to square the NRC’s characterization of safety culture as critical to safety** yet stopping way short of any regulation or requirements.)  The definitional scope of safety culture is expressed in a set of traits and related values and behaviors.  As with nuclear safety it has a limited scope and relies on abstractions emphasizing, in essence, individual morality.  It does not look beyond people to the larger environment and “system” within which people function.  This environment can bring to bear significant influences that can challenge the desired traits and values of safety culture policy and muddle their application to decisions and actions.  The limitations can be seen in the assessments of safety culture (surveys and similar) as well as the investigation of specific events, violations or non-conformances by licensees and the NRC.  We’ve read many of these and rarely have we encountered any probing of the “why” associated with perceived breakdowns in safety culture.

One exception and a very powerful case in point is contained in our post dated July 29, 2010.  The cited reference is an internal root cause analysis performed by FPL to address employee concerns and identified weaknesses in their corrective action program.  They cite production pressures as negatively impacting employee trust and recognition, and perceptions of management and operational decisions.  FPL took steps to change the origin and impact of production pressures, relieving some of the burden on the organization to contain those influences within the boundaries of safe operation.

Perhaps the NRC believes that it does not have the jurisdiction to probe these types of issues or even require licensees to assess their influence.  Yet the NRC routinely refers to “licensee burden” - cost, schedule, production impacts - in accepting deviations from nominal safety standards.****  We wonder if a broader view of safety culture in the context of the socio-technical system might better “inform” both regulatory policy and decisions and enhance safety management.

*  J.P. Dédale, "Why a Paradigm Shift Is Needed," IAEA International Experts’ Meeting on Human and Organizational Factors in Nuclear Safety in the Light of the Accident at the Fukushima Daiichi Nuclear Power Plant, Vienna May 21-24, 2013.

**  The NRC’s Information Notice 2013-15 states that safety culture is “essential to nuclear safety in all phases…”

***  "NRC Decision on FPL (Part 2)," Safetymatters (July 29, 2010).  See slide 18, Root Cause 2 and Contributing Causes 2.2 and 2.4. 

****  10 CFR 50.55a(g)(6)(i) states that the Commission may grant such relief and may impose such alternative requirements as it determines is authorized by law and will not endanger life or property or the common defense and security and is otherwise in the public interest, given the consideration of the burden upon the licensee (emphasis added).

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