'' Normal Accidents '' contributed key concepts to a set of intellectual developments in the 1980s that revolutionized the conception of safety and risk . It made the case for examining technological failures as the product of highly interacting systems , and highlighted organizational and management factors as the main causes of failures . Technological disasters could no longer be ascribed to isolated equipment malfunction , operator error , or acts of God . Perrow identifies three conditions that make a system likely to be susceptible to Normal Accidents . These are : The inspiration for Perrow 's books was the 1979 Three Mile Island accident , where a nuclear accident resulted from an unanticipated interaction of multiple failures in a complex system . The event was an example of a normal accident because it was " unexpected , incomprehensible , uncontrollable and unavoidable "
Three Mile Island accident
Three Mile Island accident
Normal Accidents