Traditional safety analyses, such as HAZOP, FMEA, FTA, and MORT, are less than effective at identifying hazards resulting from incorrect `flow` - whether this be flow of information, actions, electric current, or even the literal flow of process fluids. Sneak Analysis (SA) has existed since the mid nineteen-seventies as a means of identifying such conditions in electric circuits; in which area, it is usually known as Sneak Circuit Analysis (SCA). This paper extends the ideas of Sneak Circuit Analysis to a general method of Sneak Analysis applied to process plant. The methods of SA attempt to capitalise on previous work in the electrical field by first producing a pseudo-electrical analog of the process and then analysing the analog by the existing techniques of SCA, supplemented by some additional rules and clues specific to processes. The SA method is not intended to replace any existing method of safety analysis; instead, it is intended to supplement such techniques as HAZOP and FMEA by providing systematic procedures for the identification of a class of potential problems which are not well covered by any other method.
Whetton, C 
- Technical Research Centre of Finland, Espoo (Finland). Safety Engineering Lab.