Multidimensional Risk Assessment of Manhole Events as a Decision Tool for Ranking the Vaults of an Underground Electricity Distribution System

Even though an underground electricity distribution system is safer than an overhead system, several accidents have occurred in them. Assessing the risk of hundreds or even thousands of underground vaults is a hard task. Furthermore, given the large variability in external and internal environments and, hence, there being a wide range of possible consequences when an accident occurs, an approach to risk assessment under a multidimensional view is required. Moreover, in terms of decision making, the aggregation of the decision maker´s preferences in modeling, by multiple-criteria decision-making methods, is more complete, comprehensive, and, in particular, includes considering the decision maker´s desires. Therefore, this study puts forward a multidimensional assessment of the risks from underground vaults by generating a decision tool, which ranks the vaults in a risk hierarchy. Multiattribute utility theory was used to achieve this ranking. An application was generated to demonstrate the applicability of the model, under the following aspects of consequences: those that are human, financial, and operational; and disruptions to local vehicular traffic. The use of information arising from analysis of the differences between risks enabled the decision maker to make an in-depth analysis of the range of possibilities over which alternatives may be chosen in order to implement preventive actions.