Vulnerability Analysis against Natural and Technological Threats: A Comparative Assessment in Tehran Metropolis Gas Supply Network

Abstract

Resilience as a counterpoint to vulnerability can reduce the vulnerability of various natural, man-made, and technological threats in complex technical systems. The present study was designed and conducted with the aim of comparative assessment of the vulnerability of a gas supply network to natural and technological threats. This descriptive-analytical and cross-sectional study was carried out in Tehran metropolis gas supply network including town board stations, gas supply, and distribution networks in 2019-2020. The study was based on the vulnerability analysis method including three factors of likelihood, severity of consequences, and the degree of preparedness for threats. Comparative vulnerability assessment in these three sections of the gas supply network was performed using IBM SPSS software v. 23.0. Out of eleven identified hazardous elements, the vulnerability index for three hazardous elements was estimated as a weak level threat; four hazardous elements as a medium level threat and the vulnerability index for four hazards were evaluated as a severe threat. The results of comparative vulnerability assessment based on three parts of gas supply network showed that the highest vulnerabilities related to the gas distribution network (133.66±24.63), gas supply network (115.0±35.35), and town board stations (79.49±68.51. In addition, the results of Kruskal-Wallis test showed that the vulnerability difference in these three sections was not significant (p>0.05). The findings of the comparative assessment of vulnerability between different parts of the gas supply network including town board stations (TBS), gas supply and distribution network indicated that the resilience of these parts is relatively low and requires special attention in order to reduce vulnerability in Tehran metropolis gas supply network.