System and Task Analysis

Much has been said in safety literature about the effects of human error. Causes of accidents involving human error of some type range from an estimated 60 to 90 percent. However, root causes of these errors can often be traced to fundamental problems in the design of systems, processes and tasks related to the human activities in which these errors occurred. Sound safety planning, including hazard identification, risk management and safety assurance, must be based on a thorough understanding of the processes and activities of people in the system, and the other components of the systems and environments in which they work. Consequently, the world of aviation safety has accepted the practice of system safety and looked to the concept of safety management systems.