The proportion of dozing in all ship accidents is about 7% (2006). The purpose of this study was to investigate ship accidents caused by dozing watch-keepers. Marine accidents that had been described to the judgment record of the Marine Accidents Inquiry Agency between 1994 and 2003 were used for analysis. The authors investigated the relationship between the situations at the doze shipwreck by analyzing data that included a 30-item categorization procedure, and performing a Cluster Analysis. Analysis also included categorization of accidents according to the type of vessel and vessel use (i.e., fishing vessels; cargo ships). In both types of vessels there was a notable relationship between the situation of "The passage of time from the departure port is long" and the influence of "Work tiredness". The analysis of fishing vessels revealed there was a notable relationship between the situation of "The passage of time from the departure port is long" and the influence of both "Awake rhythm" and "Work tiredness". The analysis of cargo ships revealed there was a notable relationship between the situation of "The passage of time from the departure port is long" and the influence of "No stimulation". These results suggest that consideration of vessel type and use may be necessary in developing counter measures against dozing accidents that result from long-duration navigations.
