Zonal analysis: the final step in system safety assessment [of aircraft]

Zonal analysis is the systematic inspection of the geographical locations of the components and interconnections of a system, evaluation of potential system-to-system interactions with and without failures, and assessment of the severity of potential hazards inherent in the system installation. Zonal analysis should be performed where redundancy is used to reduce the probability of losing a critical function, because the consequence of a single undesirable event´s eliminating all of a system´s redundancy is sometimes quite severe. The value of performing a comprehensive zonal analysis is often not immediately obvious. However, in addition to future cost avoidance associated with prevented accidents, zonal analysis impresses upon the engineers involved the need to consider where their systems are installed on the product early in the design process. Zonal analysis is the final step in a proper system safety assessment