Human Factors and Human Error

Abstract

One human factors method for reducing human errors involves investigation of critical incidents to understand the dynamics and etiology of human error. This paper focuses on the use of the critical incident approach to understanding human error. Specifically, the paper describes human error scenarios that occurred at Three Mile Island (TMI), Chernobyl, Bhopal, KAL-007, and the VINCENNES incident. All of the critical incidents of human error described were caused, to some extent, by human complacency with technology, by erroneous expectancies concerning what was going on in the system and in the world, and by deficiencies in the design of equipment and the training of personnel. The major lesson learned from these critical incidents is that, to avoid such disasters, complex systems must be designed in terms of the capabilities, limitations and requirements of the personnel who operate, manage, maintain or otherwise use them. Systems personnel must be considered to be an important component of the system, to be designed into the system rather than added on after system design is complete. These accidents happened because system designers failed to take into account the needs and limitations of people in the systems. Application of human factors technology in the design of complex systems will significantly reduce the potential for similar incidents occurring in the future.