Human factors in high consequence manufacturing systems

A high consequence system is often defined as one in which the potential exists for severe or catastrophic accidents. Familiar examples include nuclear power plants, airline and other mass transportation, dams and reservoirs, and large-scale food processing. Many manufacturing systems also qualify as high consequence systems. Much of the authors` experience with high consequence systems derives from work associated with the surveillance and dismantlement of nuclear weapons for the US Department of Energy. With such operations, there exists a risk of high explosive detonation accompanied by radiological dispersal and, potentially, nuclear detonation. Analysis of major industrial accidents such as Three Mile Island, Chernobyl and Bhopal have revealed that these incidents were not attributable to a single event or direct cause, but were the result of multiple factors that combined to create a condition ripe for an accident. In each case, human error was a critical factor contributing to the accident. Consequently, many authors have emphasized the need for greater appreciation of systematic factors and in particular, human activities. This paper discusses approaches used in hazard analysis of US nuclear weapons operations to assess risk associated with human factors