Fire evacuations at wildland-urban interfaces (WUI) pose a serious challenge to the emergency services, and are a global issue affecting thousands of communities around the world. This paper presents a multi-physics framework for the simulation of evacuation in WUI wildfire incidents, including three main modelling layers: wildfire, pedestrians, and traffic. Currently, these layers have been mostly modelled in isolation and there is no comprehensive model which accounts for their integration. The key features needed for system integration are identified, namely: consistent level of refinement of each layer (i.e. spatial and temporal scales) and their application (e.g. evacuation planning or emergency response), and complete data exchange. Timelines of WUI fire events are analysed using an approach similar to building fire engineering (available vs. required safe egress times for WUI fires, i.e. WASET/WRSET). The proposed framework allows for a paradigm shift from current wildfire risk assessment and mapping tools towards dynamic fire vulnerability mapping. This is the assessment of spatial and temporal vulnerabilities based on the wildfire threat evolution along with variables related to the infrastructure, population and network characteristics. This framework allows for the integration of the three main modelling layers affecting WUI fire evacuation and aims at improving the safety of WUI communities by minimising the consequences of wildfire evacuations.

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Several traffic modelling tools are currently available for evacuation planning and real-time decision support during emergencies. In this article, we review potential traffic modelling approaches in the context of Wildland-Urban-Interface (WUI) fire evacuation applications. An overview of existing modelling approaches and features are evaluated pertaining to: fire-related, spatial and demographic factors, intended application (planning or decision support), and temporal issues. This systematic review shows the importance of the following modelling approaches: dynamic modelling structures, considering behavioural variability and en-route choice; activity-based models for short-notice evacuation planning; macroscopic traffic simulation for real-time evacuation management. Subsequently, the modelling features of twenty-three traffic models and applications currently available in practice and the literature are reviewed and matched with the benchmark features identified for WUI fire applications. Based on this review analysis, recommendations are made for developing traffic models specifically applicable to WUI fire evacuation, including possible integrations with wildfire and pedestrian models.

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Purpose The main purpose was to integrate two strategies for road safety analyses (qualitative: audits, inspections; and quantitative: accident predictions) and develop a possible protocol for the safety interventions on existing two-lane rural road segments. Those road sections do not typically belong to the TEN-network, to which the 2008/96/EC Directive is mainly oriented. Hence, they could lack of methods for designing safety-based interventions. The main research questions were:& Which possible problems can arise from the application of this protocol to real cases? & Which data are practically needed? & Which possible solutions can be provided for the highlighted problems?Methods The integrated protocol, including: 1) the HSM predictive method, 2) the EU Regulations, 3) the local road design standards, 4) some research developments; is applied to real two-lane rural road segments requiring safety-based interventions. Its application is divided in the typical road safety analysis stages. Results A wide list of possible problems was highlighted and addressed: 1) lack of data, 2) difficult comparison with current road standards in order to identify safety problems, 3) lack of methods for evaluating the skidding risk along the layout, 4) setting speed limits, 5) need for optimizing the selection of countermeasures based on their aims and their timely application, in different recurrent situations, 6) availability and comparison of predictive methods.Conclusions Based on the problems and solutions discussed, main advantages (1) the systematic approach, 2) the quantitative assessment of benefits, 3) the possible transferability) and disadvantages (difficulties in overcoming the lack of data and calibrated accident prediction models) of the method were remarked.

Wildland-Urban Interface (WUI) fires, a worldwide problem, are gaining more importance over time due to climate change and increased urbanization in WUI areas. Some jurisdictions have provided standards, codes and guidelines, which may greatly help planning, prevention and protection against wildfires. This work presents a wide systematic review of standards, codes and guidelines for the design and construction of the built environment against WUI fire hazard from North American, European, Oceanic countries, alongside with trans-national codes. The main information reviewed includes: the definition of WUI hazards, risk areas and related severity classes, the influence of land and environmental factors, the requirements for building materials, constructions, utilities, fire protection measures and road access. Some common threads among the documents reviewed have been highlighted. They include similar attempts at: (a) defining WUI risk areas and severity classes, (b) considering land factors including the defensible space (also known as ignition zones), (c) prescribing requirements for buildings and access. The main gaps highlighted in the existing standards/guidelines include lacks of detailed and widespread requirements for resources, fire protection measures, and lacks of taking into account environmental factors in detail. The main design and construction principles contained in the reviewed documents are largely based on previous research and/or good practices. Hence, the main contributions of this paper consist in: (a) systematically disseminate these guidance concepts, (b) setting a potential basis for the development of standards/guidelines in other jurisdictions lacking dedicated WUI fire design guidance, (c) highlighting gaps in existing standards/guidelines to be addressed by current and future research.

Drivers’ road familiarity is a safety-related factor. Familiar drivers may be prone to inattention and more dangerous behavior, whereas unfamiliar drivers may be affected by demanding and unexpected road environments. Previous research adequately described the role of familiarity in driving behavior and road safety performances. However, the relationships between drivers’ unfamiliarity and safety issues of road design elements are still largely unexplored and there is a lack of dedicated experimental studies. In this work, a database including run-off-road single-vehicle accidents at Norwegian rural two-lane road curves was investigated. Information about familiarity was derived from the distance from the residence of drivers involved in crashes. Road geometric variables were collected on the segment before the accident site, to provide indicators of design consistency of the previous road section. Thereafter, logistic regression was used to find relationships between predictor variables related to the geometric road design consistency and familiarity (the dependent variable). As a result of the analysis, familiarity was confirmed as a factor associated to possible dangerous behavior such as speeding in demanding road environments. However, crashes involving unfamiliar drivers are associated to unexpected curve parameters (radius and length) and the combination of horizontal and vertical curvature. Thus, as well as familiarity, drivers’ unfamiliarity may be considered as an accident factor. Moreover, some possibly useful consequences for road design are suggested for practitioners. They specifically concern provisions about radii of subsequent curves and coordination between radii of horizontal and vertical curves.

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