Abstract
Railroad shunting movements connecting and disconnecting train sets are very susceptible to human errors since they depend on human decision-making and action procedure that are variable to situation to situation. Nevertheless, in the investigation of railroad accidents, all the accident causes related with human factors have merely been categorized as 'careless treatment' of the workers without any systematic approach of behavioral sciences or the analysis of human errors. In this research, therefore, 137 accident cases occurred during railroad shunting movements and 435 accident cases occurred during driving were analyzed with a special interest of human errors. According to results, the traditional accident investigation scheme used for last several decades did not seem to be appropriate for catching up true accident causes with respect to human errors. In addition, both signal men and locomotive drivers made many mistakes in judgement/action stage while the former mainly commit judgement tasks where as the latter mainly commit cognition tasks. Ant those tasks such as 'confirmation of signal and route', 'location check-up of connected train sets', and 'route identification for a shift of track' ranked highly for accident susceptibility.