DEVELOPMENT OF COMPLEXITY INDEX OF PROBABILITY FAILURE FOR INHERENTLY SAFER DESIGN

In Inherently Safer Design (ISD) of a Process design, it’s goal is to eliminate or reduce a process's hazard. This paper discusses and prove on the simplification approach of ISD in reducing the failure frequency in a complexity of Independent Protection Layers (IPLs). Nevertheless challenging the concept of Layer of Protection Analysis (LOPA) that suggests that the more IPLs installed, the safer it is. On the other hand, This paper suggests total number of IPLs needed in a system can be limited into certain tolerable amount but still theoretically safe. By isolating the scope of the study to likelihood part only, the study is carried out accordingly.