Railway Accidents Caused by Human Error

Accident investigation and analysis are key to reinforcing and improving railway safety. Many railway accidents have been caused by degraded human performance and human error, and the tasks of train drivers and signalers have remained essentially the same. Although new technologies and equipment have gradually reduced railway operation accidents, no investigation has been conducted to investigate whether railway performance shaping factors (R-PSFs), attributed to degraded human performance, have changed or remained constant. Focusing on UK railways, this paper analyzes railway accidents involving human error for the period 1945 to 2012. The purpose of the analysis is twofold: to identify whether the number and type of factors that affect human performance and contribute to human errors have changed during this period and to assess the quality of data collected by investigation reports and to determine whether the collection of such data has evolved and improved. The analysis identifies the number of R-PSFs and their relationship to such variables as responsible personnel, immediate causes, and the time and location of the event. The contribution of those variables to the severity of an accident is calculated. Moreover, any changes in trends and patterns in the number of R-PSFs over time are explored through smoothing techniques of time series analysis. Finally, the quality of the collected data is analyzed with the data quality index. Results show that data investigation and data collection have significantly improved. However, although accident rates have decreased, the average number and type of factors that affect human performance have remained the same.