Risk assessment, based on quantitative maximum credible accident analysis (MCAA), has been conducted for a chloralkali industry situated in the midst of densely populated coastal villages. The study has made use of a software package MAXimum CREDible accident analysis version 2 (henceforth referred to as MAXCRED-II) recently developed by us.
Among the six different most credible accident scenarios developed using MAXCRED-II, the one envisaging ‘confined vapor cloud explosion followed by fire ball’ (in the hydrogen storage vessel) comes out to be the worst in terms of the highest propensity for damage (overpressure, missile, heat load). It also has the potential of causing domino effect (chain of accidents). The scenario of causing domino effect (chain of accidents). The scenario of ‘continuous release of chlorine from storage vessel’ is the second most disastrous, in terms of lethal toxic load likely over a large distance (3252 meters). In summary, the study reveals that given the masses of materials stored, and the conditions in which they are stored, there is a live risk of accidents in the storage vessels that would have far-reaching consequences. The industry thus poses a great risk to large areas of surrounding including densely populated villages (particularly Chinnakalapet and Kalapet) and the campuses of Pondicherry University and Pondicherry Engineering College.
This paper demonstrates the utilizability of MAXCRED-II and also focuses attention on the need to bestow greater effort towards risk assessment. It is hoped that these studies will make plant managers conscious of the serious consequences that can result from accidents in their vulnerable units. Appreciation of the risk, we hope, will prompt them to develop accident prevention strategies and to put in position emergency preparedness plans to cushion the adverse impacts if accidents do occur.