The involvement of human behaviour in occupational accidents: Errors in context

The information surrounding the occurrence of all traumatic work-related fatalities in Australia over the years 1982 to 1984 was analyzed. Previous analysis of patterns of accident causation revealed that pre-existing poor work practices were the most common precursors of human errors precipitating fatalities, and that, overall, this combination of causal factors was the most common one leading to fatalities. The present paper examined further the nature of work practices involved in these fatalities and their relationship to subsequent behavioural events in the accident sequence. The most common work practices were those associated with procedures, either originating from management or individual practices. Examination of the association of particular work practices with the occurrence of subsequent human errors revealed that the origin of the unsafe practice varied for different error types. Individual worker practices, safety equipment and personal protective equipment practices were all associated with later skill-based errors. In contrast, management practices were associated with knowledge-based errors, while general equipment practices were associated with rule-based errors. These findings provide evidence for the view that aspects of work organization provide the circumstances in which later events may precipitate the accident. Moreover, the data suggest that being able to identify the precursors of critical events, and, in particular, those events that are difficult to directly target, can provide a specific focus for prevention. Knowledge-based errors can be directly targeted for prevention, whereas for skill-based errors the only avenue for prevention lies in targeting the surrounding circumstances. (C) 1997 Elsevier Science Ltd.