A semiautomatic method for qualitative failure mode analysis

Failure mode and effects analysis, and fault tree analysis are two established techniques for studying the reliability of large systems. The method described in the paper is a formalized version of 'cause-consequence analysis' which is a diagrammatic technique for presenting the sequence of events leading to a failure, and the conditions under which these events can take place. The methods described here are directed especially to those cases where sequence is important, particularly sequential controllers, computer control, and the checking of written operating procedures. An example is given (a pump and a reservoir) to demonstrate the construction of cause-consequence diagrams