The panel agreed to eliminate the factors of ship age, ship structure, natural catastrophes, and the close proximity of marine facilities through interactive discussions with respect to the characteristics of the accidents in history. Wind speed, wind direction, sea state, visibility, and current were categorized into a single main factor, ‘Weather/sea conditions’. Waterway was described as ‘Channel conditions’. Weather·sea condition and channel condition are classed as environmental factors. A traffic-related factor was specified as ‘Volume of traffic inside a port’. ‘Vessel size’ and ‘Vessel type’ were also included as the main factors. Fog, gale, wave height and tide were chosen as sub-factors of ‘Weather/sea conditions’. It is noteworthy that current was changed into tide because the Yellow Sea near the Korean peninsula has a large tidal range. Channel conditions were taken into account from the perspectives of depth, complexity, and width. For efficient evaluation, traffic volume was divided into heavy, average, and light. Vessel size was classified in an interval from 40,000 DWT to 100,000 DWT . Vessel type was divided according to the types of ships operating in Korean ports. In addition, the volume of traffic inside a port, ship size and ship type are classed as non-environmental factors.