Citation

Hollnagel E. Hum. Factors Aerosp. Safety 2004; 4(3): 169-179.

Copyright

(Copyright © 2004, Ashgate Publishing)

DOI

unavailable

PMID

unavailable

Abstract

Efforts to account for incidents and accidents usually include one or more instances of human actions gone wrong, which in turn are explained as 'human error'. An abundance of theories, models and methods have been developed to help clarify what exactly 'human errors' are and how they can be reduced, although with limited success. Most of this research has focused on what happens when things go wrong, and has neglected to look at what happens when things go right. This paper argues that we cannot understand the former without understanding the latter, and that we therefore need theories and models of normal actions rather than of 'human error'. It is proposed that both normal performance and failures should be explained in terms of how people adjust their actions to achieve an acceptable compromise between resources and demands, hence that neither can be attributed to nor explained by failures of specific components or functions. The paper discusses how human performance can be seen as a dynamic trade-off between efficiency and thoroughness, taking place both at the sharp end and the blunt end.