Using risk matrix as an inherent risk tool at preliminary design stage for inherently safer design

Abstract

Safety should be considered and addressed in the whole life cycle of a process system or facility. They are many established methodologies to identify, analyze, prioritize and manage risks arising from different stages. One of the design methodologies to reduce and eliminate root causes of hazards during design stage is known as Inherent Safety (IS). The principles to defining IS were formalized by Prof. Trover Kletz and were further developed into guidelines that are more definitive by a number of researchers. An inherently safer process plant could be designed if the information on risk levels, likelihood and severity could be known earlier at the preliminary design stage. The risk levels, likelihood and severity could be reduced or eliminated by applying the principle of inherent safety in the design. However, process designers normally lack of information on risk levels, likelihood and severity from process plant during preliminary design stage. This information is available once Quantitative Risk assessment (QRA) study is completed at the end of detail design stage prior to plant construction as required by law. Therefore, this research aims to overcome this problem by developing an inherent risk tool that can determine the risk levels, likelihood and severity early in the preliminary process design stage and at the same time to provide the opportunity for process designers to apply inherent safety principles for inherently safer process design.