Risk Assessment of Ilam Gas Refinery Storage Tanks using Safety Weighted Hazard Index (SWeHI) and recommending required control measures

risk assessment is the most important tool for identifying unacceptable risks and preventing accident from occurring. In this study, the Safety Weighted Hazard Index (SWeHI) was used for assessing the risks associated with the storage tanks of the Ilam gas refinery company.

SWeHI has two parts to be determined: the potential hazard index (B) and the hazard control index (A). B can come into two forms: the fire and explosion hazards (B1) and toxic release hazard (B2). Both these forms should be computed separately and the higher one will be considered as B. For calculating A, all protection layers in place are assessed and quantified. SWeHI is calculated by dividing B by A.

B1 values for atmospheric and spherical tanks were 347.31 and 269.16, and B2 values were 97.48 and 169.34, respectively. A value for all tanks was 84.31. Among factors affecting A, emergency management plan and the reliability of equipment were the most challenging ones. SWeHI grand scores were 3.1925 and 4.1993 for spherical and atmospheric tanks, respectively.

Compared to other similar indices, SWeHI is a more quick and straightforward technique for risk assessment and remedial measures prioritization in oil and gas industries.