Matrix of Fire Hazard Factors for Overhead Power Lines as a Basis for Risk Modeling

Introduction. Studies of fire risks associated with overhead power lines (OHPLs) consider combustible materials, terrain, and meteorological conditions. The mechanisms of fire occurrence and spread have been studied, and quantitative risk modeling is being developed based on incident statistics. However, these scenarios rely on arbitrary or poorly defined sets of initial factors, making it difficult to create unified risk management systems. This scientific work aims to fill this gap by creating a unified classification of fire hazard factors for overhead power lines that takes into account the causes, environment, and development of fires. A scenario-based risk matrix for OHPLs is built on this foundation. Materials and Methods. The basis of the study was a method for assessing fire risk, which considers fire from overhead power lines as a result of the interaction between three key components: the ignition source, combustible medium and fire propagation conditions. Through an analysis of the relevant literature, these components were broken down, classified, and the principles for systematizing them were identified. Results. Ignition sources, combustible medium, and fire propagation conditions were presented as axes in the scenario matrix of fire risk associated with overhead power lines. These factors were classified and structured using author-created diagrams. The first one included the types of short circuits, heating, and ignition mechanisms. In the second, four classes of materials were differentiated by their sensitivity to fire. The third one described three categories of fire propagation conditions. The risk level and critical ignition energy were mathematically represented. The final matrix aggregated four classes of material: high-sensitive, medium-sensitive, low-sensitive, and specific. Fire spread conditions were divided into favorable, moderate, and unfavorable. Taking into account the ignition sources (interphase and single-phase), the risk levels were determined: low, medium, high, and critical. Discussion. The matrix combined 24 typical scenarios of the studied hazard (two groups of sources × four classes of materials × three categories of propagation conditions). Five scenarios (approximately 21%) were critical. As a rule, they occurred with a combination of high-energy emergency conditions, high- and medium-sensitive materials and adverse weather conditions. The matrix can be used in the transition from a qualitative description of OHPLs to a quantitative assessment of the probability of a fire and its consequences. This innovation will be beneficial for modeling OHPL incidents, refining safety measures, and improving risk assessment. Scenarios can be ranked based on importance, allowing for a more efficient allocation of resources for protective measures. Conclusion. The new approach, in contrast to the traditional one, makes it possible to overcome the limitations of the fragmented hazard assessment and systematically analyze fire scenarios related to overhead power lines. This allows us to justify decisions on modernizing and strengthening the protection of individual network sections, i.e., to focus investments on infrastructure elements and typical situations that fire risks depend on to a greater extent. Future research in this area is expected to: supplement accident statistics and the amount of experimental data on the energy characteristics of ignition sources; provide a quantitative parameterization of the function that represents the risk level for each scenario; set numerical thresholds for four risk levels.