ABSTRACT
Error is an inherent part of all human activity. Feedback from errors allows us to build and develop skills. Action errors can be seen as an inevitable consequence of the organisation of skilled behaviour. Errors have been classified into four groups: mistakes, slips, lapses and violations. Complex skills often include the need to remember to do something at a later time or place (‘prospective memory’). Failures here range from the commonplace (e.g. leaving the last sheet of paper on the photocopier) to the catastrophic (e.g. missing a vital step on a checklist). The importance of workplace errors was brought to light in the 1930s and led to the development of Heinrich’s ‘domino model’ of accident causation. Versions of this ‘chain of events’ model have had a major impact on accident investigation and safety management ever since. A modern version of the model was developed by Reason who drew a clear distinction between the errors made by workers (‘active failures’) and errors made earlier elsewhere in a system known as ‘latent failures’ or ‘latent conditions’. This led to a period of intense interest in organisational aspects of system failure. A number of error analysis and classification techniques (e.g. TRIPOD and HFACS) have been developed from these theoretical backgrounds.
