Failure modes and effect analysis (FMEA)
This approach systematically examines the failure modes of each component, without however, focusing on relationships among the elements of a complex system.
Fault Tree Analysis (FTA)
A system failure is proposed and then events are traced back to possible causes at the component level. The reverse of the fault-tree analysis is ‘event – tree analysis’. This method most effectively illustrates the disciplined approach required to capture as much as possible of everything that affects proper functioning and safety of a complex system.