A HUMAN-FACTORS METHODOLOGY FOR SAFETY ASSESSMENT BASED ON THE DYLAM APPROACH

This paper discusses how the problem of human factors can appropriatel y be included in a probabilistic safety study. During incidents, the e ffect of the plant dynamic evolution and the failures of components ca n lead to nonintuitive configuration of the system and, when the inter action of the operator and the control and protection system is accoun ted for, the overall scenario of the safety study becomes particularly complex. These problems demand the use of a dynamic reliability metho dology technique and the development of an appropriate model of human behavior to be coupled to a taxonomy of erroneous actions. At JRC thes e two endeavors have been carried out by the DYLAM approach and by a n umber of modeling architectures of operator simulation, which have bee n coupled for the development of a dynamic methodology for human facto rs analysis. In the paper, a simple application case is shown by the s tudy of the control of an Auxiliary Feedwater System during incidental conditions.