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?
- 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."
- 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."
- 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."
- Commitment to resilience - "They develop mechanisms for catching and recovery from small failures before they cascade through multiple subsystems of an organization."
- 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."