California’s natural gas infrastructure is essential to the state’s energy system yet it still remains highly vulnerable to the combined effects of seismic events and fire activity. Traditional assessment approaches often overlook these interactions, limiting themselves to resilience planning. To bridge this gap, this thesis develops a quantitative, performance-based framework that integrates seismic hazard characterization, infrastructure vulnerability, and fire behavior into a unified multi-hazard analysis. Applied to the San Francisco Bay Area through QGIS and the OpenSRA platform, the framework highlights where vulnerabilities concentrate and how cascading impacts may develop across interconnected systems. The findings show that compound risks are shaped by the convergence of physical conditions, infrastructure characteristics, and surrounding urban environments.