Risk and consequence analysis of ammonia storage units in a nuclear fuel cycle facility

Industrial disasters, such as unintended toxic gas releases resulting in fires, explosion, and fatalities, are damaging both the global ecology and the social acceptance of the related technology. Risk and consequence analysis is the key feature of process safety measures for the protection of environment and human life. In this work, the risk and consequence analysis of unintended release of anhydrous liquid ammonia for one of the storage tanks, located inside the nuclear fuel cycle facility, was analyzed for leakages leading to exposure of surrounding human population and fire with allied thermal radiation risk. The risk assessment was performed using four methods: Fault tree, E&FI methodology, Probit, and ALOHA, It was observed that while the predicted hazard severities from fault‐tree analysis, Probit analysis, and ALOHA nearly converged, the conventional F&EI, the safety workhorse of the chemical industry estimated low numeric values of the respective hazard. A methodology was proposed to load this general F&EI value for the case of chemical plant being located inside a nuclear facility. Overloaded F&EI procedure estimated hazard value for envisaged unintended ammonia release in good agreement, with results from FTA, Probit, and ALOHA analyses.