RELIABILITY-ANALYSIS AND OPERATOR MODELING

The paper considers the state of operator modelling in reliability ana lysis. Operator models are needed in reliability analysis because oper ators are needed in process control systems. HRA methods must therefor e be able to account both for human performance variability and for th e dynamics of the interaction. A selected set of first generation HRA approaches is briefly described in terms of the operator model they us e, their classification principle, and the actual method they propose. In addition, two examples of second generation methods are also consi dered. It is concluded that first generation HRA methods generally hav e very simplistic operator models, either referring to the time-reliab ility relationship or to elementary information processing concepts. I t is argued that second generation HRA methods must recognise that cog nition is embedded in a context, and be able to account for that in th e way human reliability is analysed and assessed. (C) 1996 Elsevier Sc ience Limited.