Inherently safer design protocol for process hazard analysis

Abstract

Inherently safer design (ISD) is a component of industrial safety that focusses on the elimination and reduction of hazards using four principles – minimization, substitution, moderation and simplification. Process hazard analysis (PHA) has been identified as an opportunity to explicitly consider ISD and enhance the implementation of ISD within process safety management (PSM) frameworks. The PHA technique of interest for this study was the bow tie methodology.The objective of this work was to develop a protocol to identify ISD-based barriers in bow tie diagrams. Example-based guidance was used to identify potential ISD opportunities. The protocol was validated using a case study from Contra Costa County Health Services. Protocol validation demonstrated the ability of the protocol to identify potential ISD barriers. This protocol validation is presented in this paper. Degradation factors and controls of identified barriers, including ISD barriers, are important considerations to ensure their effectiveness. Recommended future work is further protocol validation in a predictive manner in an industrial organization.