抄録
I introduce topics related to the investigation of railway accidents and some examples of accidents which happened after the serious accident in Hibiya line of Teito Rapid Transit on March of 2000. In the first part I describe the countermeasures and activities after the Hibiya accident and the "Aircraft & Railway Accident Investigation Commission", that was organized officially from this October. In the main part I introduce several examples of railway accidents during this one-year, such as train head-on collisions in Keifuku Electric Railway, and try to consider the causes and backgrounds of the accidents from the point of view of safety engineering. Especially redundancy and fail-safe of brake system are considered.