Assessing Vulnerability and Fire Risk in Old Urban Areas: Application to the Historical Centre of GuimarAes

Urban risk mitigation is a priority in city management due to the severe consequences and costs that disasters can cause. Several efforts are focused on disaster prevention through the definition of pre-disaster actions, especially in highly vulnerable urban areas. In that sense, historical centres represent one of the main challenges for risk mitigation due to two inherent characteristics: their heritage value, related to their historic importance, economic role and social symbolism; and their high vulnerability, resulting from the condition of old urban areas, usually complex in terms of architectonic, constructive and urbanistic development. Considering the abovementioned, the present work focuses on the fire risk assessment of the Historical Centre of GuimarAes, in Portugal. The assessment was developed through the application of an index-based fire risk assessment method to the 436 buildings that comprise this UNESCO World Heritage Site. After being integrated into a geographical information system tool, the assessment results were spatially analysed and discussed in the form of vulnerability and risk maps. Analysis revealed that about 67% of the assessed building stock have a moderate to high fire risk. From the analysis of the sub-factors that compose the Fire Risk Index method, it was further possible to perceive that this situation is not only associated with the characteristics of the buildings, but also to the inner characteristics of the urban area itself. Taking into account the scale and aim of the study, the results obtained in this work were found to be reliable, allowing for identification of the most vulnerable buildings in respect to fire risk.