Abstract
In this paper, we focus on a design of the alarm system as a first step to develop a design methodology of IPL (Independent Protection Layers) [1] based on PHA (Process Hazard Analysis). We present a design method based on HAZOP (Hazard and Operability Study) to develop two kinds of alarm systems separately, i.e. one is for cause identification, and the other is for consequence mitigation. The effectiveness of this study is illustrated through a case study for Hydro Desulfuration (HDS) process.
