Friday, March 28, 2014

Lessons on the Anniversary of the Three Mile Island Accident

Today marks the anniversary of the infamous Three Mile Island nuclear accident.  It occurred on March 28, 1979.  Given the date, I thought that I would share a few lessons from that catastrophic failure.  Here are a couple short excerpts from a book chapter that I wrote several years ago about catastrophic failures. 

Research on catastrophic failures traces its roots to a groundbreaking study of the Three Mile Island nuclear power plant accident and the development of normal accident theory.  In his 1984 book, Normal Accidents, Charles Perrow examined the structural characteristics of organizational systems that involve high-risk technologies such as nuclear power.  Perrow’s conceptual framework classifies all high-risk systems along two dimensions: interactive complexity and coupling.  Interactions within a system may be simple/linear or complex/nonlinear.  Coupling may be either loose or tight.  Perrow argues that systems with high levels of interactive complexity and tight coupling are especially vulnerable to catastrophic failures.  In fact, he argues that accidents are inevitable in these situations; certain failures constitute “normal accidents.”  Perrow concludes that, “Normal accidents emerge from the characteristics of the systems themselves.  They cannot be prevented.” 

Later in the chapter, I talk about more recent research that has examined "high reliability organizations" - that is, entities that operate complex systems with a high degree of safety.  

 As researchers began to gain a better understanding of why catastrophic failures occurred, a group of scholars started to work concurrently to study complex organizations that have operated with very, very few major safety incidents for many years.   Scholars coined the term “high reliability organizations” (HRO) to describe these entities... They have studied organizations such as aircraft carriers and air traffic control centers.   The error rates for these organizations are remarkably low, given the hazardous conditions in which they operate... In 2001, after roughly a decade of HRO research, Weick and Sutcliffe wrote a book, titled Managing the Unexpected, in which they tried to synthesize and integrate what they and others such as Karlene Roberts had learned about these complex organizations that performed very reliably in hazardous conditions.  They coined the term mindfulness to describe the simultaneous existence of five key characteristics of HROs.   

What are these five key characteristics of high reliability organizations?
  1. Preoccupation with failure - "They did not dismiss small deviations, or settle on narrow, localized explanations of these problems. Instead, they treated each small failure as a potential indication of a much larger problem." 
  2. A reluctance to simplify interpretations - "HROs try to maintain a healthy diversity of perspectives within the organization, and they constantly test their simplified models of reality."
  3. Sensitivity to operations. - "They do not allow the emphasis on the big picture – strategic plans, vision statements, etc. – to minimize the importance of front-line operations, where the real work gets done."
  4. Commitment to resilience - "They develop mechanisms for catching and recovery from small failures before they cascade through multiple subsystems of an organization." 
  5. Deference to expertise -  "HROs ensure that expertise is tapped into at all levels of the organization. They push decision-making authority down, and they migrate decisions in real-time to the location in the organization where the most relevant expertise lies."

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