Identifying Human Settlements Vulnerability to Wildland-Urban Interface (WUI) Fire: A Review

Abstract The devastating impacts of Wildland-Urban Interface (WUI) fire events on residential buildings and their occupants have been recurring extreme events throughout human history. In the last 1.5 decades, the world has experienced a notable surge in the occurrence of large outdoor fires that resulted in significant impacts on the built environment. With population growth, climate change, and a lack of policy effort, there is a strong likelihood that the Wildland-Urban Interface (WUI) fire problem will worsen in the coming years. The purpose of this study is to review existing publications and literature on previous records of WUI fire events from various historical periods in countries around the world in order to identify shared physical characteristics of vulnerable features of human settlements that contribute to the loss of property and life of its occupants during a WUI fire. Previous studies regarding post-fire investigations indicate that the ways in which structures are exposed to and subsequently impacted by WUI fire may vary depending on the specific event. The review of relevant publications and literature shows that there are several physical human settlement features that are particularly vulnerable to fire, namely: roofs (eaves and gutters), timber decks, windows, and vents. Additionally, there were different strategies identified such as location and density management, consideration of appropriate building design and construction material, and management and maintenance of vegetation and other fuel sources to reduce the risk of WUI fire to human settlements. The limitation of this study lies in its reliance on existing publications, without accounting for different climatic and country variations.