Inherent Safety Index Module (ISIM) to assess inherent safety level during preliminary design stage

One of the acceptable methods to quantify the level of inherent safety is based on the inherent safety index. This paper reviews presently available techniques for quantification of inherent safety level in a design and addresses the shortcoming of current techniques by proposing direct integration of a process simulator with inherent safety index. This integrated index, known as Inherent Safety Index Module (ISIM), is one of the modules developed in a newly proposed framework to determine inherent safety level in the preliminary design stage. This framework is an enhancement of the framework developed earlier [10]. This new framework allowed process information from a process design simulator to be extracted and analysed for the determination of Inherent Safety Level (ISL), and consequences and probability of unwanted incidences. The availability of such information at an early stage of design will help process designers obtain ISL that will assist in producing safer designs through the application of inherent safety principles in a more efficient and cost effective manner. This paper also presents an overall concept of the proposed framework for the development of an inherent safety tool. A case study illustrated the benefit of having inherent safety index known to process designers during the preliminary design stage. With the right information, modifications to conditions of process can be carried out and thus leading to safer process plants