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In this paper, a pyrolysis model for a PVC cable is constructed using results from thermogravimetric analysis, microscale combustion calorimeter and cone calorimeter experiments. The pyrolysis model is used to simulate fire propagation in horizontal cable trays. The simulated arrangement corresponds to a cable tray fire experiment from OECD PRISME 2 project. As laying the cables loosely along the horizontal trays is a random process, a novel stochastic method is developed for making the simplified cable tray geometries for the computational fluid dynamics model. In addition, as the simplified cable tray geometry has significantly smaller surface area than a real tray full of cables, the surface area was parametrically adjusted. In contrast to most of the earlier published numerical approaches for simulating cable tray fires, the presented approach does not use empirical correlations for predicting fire propagation and does not require any results from full-scale experiments for calibrating the model. The simulation results are compared to experimental results in terms of heat release rate, mass loss, tray ignition times and lateral flame spread rates. The maximum heat release rate was overpredicted by 8% on average.

In recent years, fires in tall buildings have become more frequent, which costs billions of dollars each year and the loss of many human lives. The facade fire in the Grenfell tower made the structure uninhabitable, and the collapse of the three World Trade Center (WTC) towers is the total structural failure caused by fire. Despite such events, no well-defined methodology exists to reconstruct both fire and structural behaviors and carrys out the forensic investigation of a building fire. This Part I paper collects the evidence of the Plasco Building fire and generates a coherent timeline to reconstruct the fire processes. The vertical and horizontal fire spread of the building is reconstructed using computational fluid dynamics (CFD) fire modeling and calibrated against the evidence library. The spatio-temporal temperature history from the fire modeling provides realistic fire scenarios to simulate the structural response. The fire simulation results are used as boundary conditions to be transferred to a finite element analysis tool for a detailed structural analysis to determine the likely collapse mechanism of the Plasco Building in Part II. The methodology presented in this paper to reconstruct the fire can also guide the structural fire safety engineers to improve the building fire-safety and life-safety strategies.

Vehicle fires in parking structures developing into large conflagrations are rare but can result in severe economic losses. It is important to understand the hazard posed by modern vehicle fires to determine whether current fire codes for parking garages are mandating adequate fire protection requirements. There has been an increase in the fire hazard from changes in vehicle design and increased use of plastics and other combustible materials in vehicle construction, along with denser parking of vehicles in parking structures. This manifests as faster flame spread within the vehicle, easier ignition and more rapid fire spread to neighboring vehicles. Based on the findings, test data from vehicles older than 2000–2005 model years should not be used as basis for development of codes and regulations. Open parking structures emerge as the main area of concern regarding fires in modern vehicles. The lack of any requirements for active protection systems in the fire codes, and trends in vehicle and garage design suggest that large, devastating fires in these structures could become increasingly common. The spread of fire between vehicles, especially from the initial to the second and third vehicles, is critical in determining the extent of the fire and the ability of the fire department to successfully control and extinguish. Future research should be conducted into earlier detection, sprinkler protection, and fire spread between vehicles to address the hazard.

To date, the efficiency and effectiveness of early warning systems of satellite imagery for preventing and mitigating wildfire remain a challenging issue. The heat of pre-ignition ( $$Q_{{{\text{ig}}}}$$ ) can be an index of fire likelihood, which is further enhanced with remotely sensed data, active fire data, and fuels information for operational application of satellite imagery in fire early warning systems. $$Q_{{{\text{ig}}}}$$ is a prerequisite for forest fires by the side of ignition sources and weather. This study analyzed the effect of $$Q_{{{\text{ig}}}}$$ variation on fire occurrences to develop a remote sensing-based initial fire likelihood index for identifying areas that have a high probability of fire. In this study, $$Q_{{{\text{ig}}}}$$ of Rothermel’s fire spread model daily data is retrieved at 1 km pixels from MODIS data. MODIS active fire products were used to interpret the $$Q_{{{\text{ig}}}}$$ of fuels for 10 days before the days of fire occurrences in November 2010 to determine the pre-fire conditions. A formula for converting $$Q_{{{\text{ig}}}}$$ into an initial fire likelihood index (IFLI) was then used by binary logistic regression method. Analyses show that there was a positive association between suggested IFLI and fire occurrences during the study period with a fair diagnostic accuracy of 92%, and 80% for dead and live fuels, respectively. Mann–kendall test suggested that there are significant trends in the fuel moisture content time-series for both live and dead fuels. Further analysis using the Hosmer–Lemeshow test represents that the models showed an acceptable fit. The suggested IFLI is an effective tool for fire management decision-making whenever a near real-time fire likelihood is required.

The expanded polystyrene (EPS) facade has been widely used to save building energy, but it has also caused many severe facade fire accidents worldwide. Especially for aged buildings, the naturally weathered exterior surface layer can further increase the facade fire risk and the fire spread rate (FSR). In this work, a series of real-scale EPS External Thermal Insulation Composite System (ETICS) facades are tested via the JIS A 1310 standard. The EPS thickness varies from 100 to 300 mm, density changes from 15 kg/m3 to 30 kg/m3, and heat release rate (HRR) of window spilled flame ranges from 600 kW to 1100 kW. Tests showed that the surface cement layer was quickly damaged by a spilled flame that provided negligible fire resistance for the internal flammable EPS panel. The measured upward FSR increases with the rising of HRR and with the decreasing EPS thickness like the thermally thin material. An empirical correlation of instantaneous upward FRS is proposed, FSR = 0.22Φ + 3.45 [cm/min], where Φ is a modified fire propagation index derived from the experimental temperature distribution. In addition, a simple prediction method for FSR is proposed for the facade fire and verified by the experimental data. This work provides a useful method to quantify the upward facade fire propagation, which also helps evaluate the fire risk and hazard of EPS ETICS facade prior to the costly large-scale tests and installation.

A qualitative assessment of fire hazard posed by laminated glass balcony balustrades was carried out through an in-depth analysis of empirical evidence from six (6) past balcony fires with glass balustrades to deduce the type of glass used and understand the mechanism for fire spread in these fire scenarios. Post-fire conditions of these balconies were studied based on their post-breakage integrity and presence of decolourisation/delamination in order to determine the type of glass used in these balconies. A visual observation of the overall fire spread during the fire and extent of damage post-fire was then carried out to determine whether there was a correlation between the type of glass used and the extent of fire spread. It was found that fire spread was mainly driven by combustible materials around the balcony construction as the fire damage on the balustrades was limited to the area in the vicinity of the combustible materials and the balustrade glass did not contribute to the fire. Given the current regulatory framework in England that limits the use of laminated glass in balcony balustrades from a fire safety perspective despite its architectural benefits and structural safety, this study shows that there is no evidence that the use of laminated glass would constitute a fire hazard when used as glazed balcony balustrading.

Fire has been an integral part of the Earth for millennia. Several recent wildfires have exhibited an unprecedented spatial and temporal extent and their control is beyond national firefighting capabilities. Prescribed or controlled burning treatments are debated as a potential measure for ameliorating the spread and intensity of wildfires. Machine learning analysis using random forests was performed in a spatio-temporal data set comprising a large number of savanna fires across 22 years. Results indicate that fire return interval was not an important predictor of fire spread rate or fire intensity, having a feature importance of 3.5%, among eight other predictor variables. Manipulating burn seasonality showed a feature importance of 6% or less regarding fire spread rate or fire intensity. While manipulated fire return interval and seasonality moderated both fire spread rate and intensity, their overall effects were low in comparison with meteorological (hydrological and climatic) variables. The variables with the highest feature importance regarding fire spread rate resulted in fuel moisture with 21%, relative humidity with 15%, wind speed with 14%, and last years rainfall with 14%. The variables with the highest feature importance regarding fire intensity included fuel load with 21.5%, fuel moisture with 16.5%, relative humidity with 12.5%, air temperature with 12.5%, and rainfall with 12.5%. Predicting fire spread rate and intensity has been a poor endeavour thus far and we show that more data of the variables already monitored would not result in higher predictive accuracy., Journal paper published in: Stochastic Environmental Research & Risk Assessment

Aiming at the current research on the escape path of complex building fires with the problem about lack of path prediction correction and multi-person escape, this paper proposes an analytical method of real-time dynamic escape path prediction based on Building Information Model (BIM). The method uses a Fire Dynamic Simulator (FDS) to simulate the spread of the fire and analyzes the simulated data of BIM model, and dynamically adjusts simulation of the spread of fire according to the real-time situation of fire. This method is designed for path planning for the single and multi-person escapes. The single-person escape path planning uses real-time dynamic methods to locate the evacuee and obtain the fire situation. The Dijkstra algorithm is used to derive the shortest escape route with BIM integration information, and the fire spread simulation data and escape speed are used to predict and correct the path to achieve the best escape path planning in real-time dynamic. The multi-person escape path planning predicts the congestion according to the single-person escape route. When the congestion is predicted, the corresponding evacuation process is carried out to avoid the hazard caused by the fire escape and crowding so as to realize rapid escape at the scene of fire. Through the BIM 3D model, the dynamic fire escape path can be visualized for the evacuees. The effectiveness of the proposed method is verified by constructing a prototype system for the analysis.

Biomass burning is one of the critical components of the Earth system, significantly affecting atmospheric emissions and carbon budgets. Fires occurring in the interface between wildland and urban areas also have important socioeconomic effects, affecting people’s lives and resources. Even though fires are natural in many ecosystems, climate and societal changes have recently caused particularly severe fire seasons (Australia, California, Amazonia, Portugal…). Mitigating the negative impacts of fire requires further efforts to assess fire danger conditions. Satellite Earth observation provides considerable capabilities to evaluate the different variables involved in fire danger. Data obtained from remote sensors offer information on possible sources of fire ignition, on fuel status and abundance, and on the topography and the meteorological conditions that will affect fire spread. Satellite observations also provide near-real-time information on fire occurrence for early response teams. This article describes the different variables affecting fire danger and illustrates how satellite data can offer useful information to estimate these variables, focusing on global and continental fire danger systems.

Globally, the number of informal settlement dwellings are increasing rapidly; these areas are often associated with numerous large fires. Unfortunately, until recently, very little research has been focused on informal settlement fire issues leaving any attempts to improve their fire safety lacking the evidence base to support effective-decision making. However, over the past 4 years, a limited number of researchers have looked at better understanding these fires through full-scale experimentation and numerical modelling; starting to provide the necessary evidence base and future research directions. It is with this background in mind that this paper seeks to provide a more fundamental understanding of the effect of dwelling separation distance on informal settlement fire spread based on full-scale experiments and analytical equations. In this paper two full-scale experiments were conducted. Both experiments consisted of multiple dwellings, with the main difference between the experiments being the separation distance. Fire spread times, heat release rates, door and window flow velocities, ceiling temperatures and incident heat fluxes were recorded and are reported for both experiments. Theoretical neutral planes are derived and compared to the experimental neutral planes, which show relatively good correlation. The paper continues by calculating the expected incident radiation and time-to-ignition, using the flux-time product method, of the two fire scenarios (i.e., the two experiments) through means of analytical equations, and these findings are compared to the experimental results. Through configuration factors, the paper shows the effect of separation distance, dwelling height and dwelling length on the times-to-ignition, where it is clear that the heat flux received by an adjacent dwelling decrease approximately exponentially as the distance between dwellings increases, and consequently, the time-to-ignition increases exponentially as the separation distance between dwellings increases.

Extreme fire events in tunnels can have catastrophic consequences, including loss of lives, structural damage, and major socioeconomic impacts. The fire scenario itself is one of the primary parameters that would influence the level of damage in a tunnel. Standard hydrocarbon fire temperature–time curves exist but they are idealized and do not consider the actual fire duration and potential for fire spread within the tunnel. Furthermore, risk-based decision-making frameworks and performance-based design of tunnel linings require realistic sets of fire scenarios to quantify damage. This paper focuses on quantifying uncertainties in the temperature–time evolution of railway tunnel fires considering fire spread between train cars. In this study, 540 numerical simulations are conducted in fire dynamics simulator by varying ventilation velocity, amount of fuel, tunnel slope, ignition point, and criteria for fire spread between railcars. Temporal and spatial distribution of fire temperature in the tunnel is studied. The resulting 540 temperature–time curves at sections with the highest temperature are analyzed and statistics of the maximum fire temperature and duration, heating rate, and decay rate are provided. Fires with heat release rates larger than 40 MW are categorized as high-intensity with mean maximum temperature of 1007°C. Fires with heat release rates smaller than 30 MW are categorized as low-intensity with a mean maximum temperature of 245°C. The proposed framework can be expanded in future to establish guidelines for temperature demands in the design of concrete tunnel linings within risk-based frameworks to achieve required performance levels in railway tunnel fire events.

Fuel moisture content is one of the important factors that determine ignition probability and fire behaviour in forest ecosystems. In this study, ignition and fire spread moisture content thresholds of 40 dead fuel were performed in laboratory experiments, with a focus on the source of ignition and wind speed. Variability in fuel moisture content at time of ignition and during fire spread was observed for different fuels. Matches were more efficient to result in ignition and spread fire with high values of fuel moisture content compared to the use of cigarette butts. Some fuels did not ignite at 15% moisture content, whereas others ignited at 40% moisture content and fire spread at 38% moisture content in the case of matches, or ignited at 27% moisture content and spread fire at 25% moisture content using cigarette butts. A two-way ANOVA showed that both the source of ignition and the wind speed affected ignition and fire spread threshold significantly, but there was no interaction between these factors. The relationship between ignition and fire spread was strong, with R2 = 98% for cigarette butts, and 92% for matches. Further information is needed, especially on the density of fuels, fuel proportion (case of mixed fuels), fuel age, and fuel combustibility.

Wildland fires and wildland–urban interface (WUI) fires quite often become the focus of discussion among fire researchers whenever large outdoor fires are the topic, especially because of their global occurrence and their potential for causing serious damage. But at the same time, large urban fires have been occurring in Japan especially after major earthquakes or with high winds, at densely built urban area consisting of old wooden houses. Normally, fire spread is caused by three mechanisms: flame, radiation, and firebrands, especially in the cases of wildland fires, WUI fires, and large urban fires. And what is common between WUI fires and large urban fires is structure–structure fire spreading. In Japan, “Taika” (large urban fire) is a fire when the total burnout floor area is 33,000 m2 or more. The present paper first discusses the history of large urban fires in Japan, then examines the national standard regulations for fire safety in Japan aimed at mitigating the damage caused by those fires. Finally, an overview of current scientific research in methods of controlling urban fires in Japan is provided. This paper compiles such impotent information on large urban fires in Japan, which is the novelty and merit in this work. Furthermore, the contents in this paper will be contributing to the progress of new project ISO/TR 24188 on “Large outdoor fires and the built environment—Global overview of different approaches for standardization”, at ISO/TC92/WG14 “Large outdoor fires and the built environment”.

Combustible facade systems used in modern buildings envelops have received much attention in recent times due to their involvement in propagation of accidental fires in such buildings. This study presents findings from four full-scale real fire experiments performed on a three-story structure (each room being of plan dimensions $$10'\times 20'$$ and story height $$10'$$ ) with combustible facade systems involving firestops, aluminum composite panels and glass. Two experiments simulated external fire-spread mechanism through the leap-frog effect (one with external fire source and one with internal fire source). The other two experiments were designed to study internal fire spread mechanism due to failure of firestops, a crucial design component of facade systems which is overlooked by most standardized facade fire tests. The experiments indicated that a facade fire can reach from one story to the next in about 3 min and hence, can severely limit the response and egress time for higher floors of a building. Further, the experiments showed that the facade system was exposed to heat flux levels in excess of $$100\,\mathrm{kW}/\mathrm{m}^{2}$$ with maximum temperatures reaching $$1000^{\circ }\mathrm{C}$$ . The existing testing standards consider lower incident flux levels and the gas burners used in most existing test methods can reach maximum temperatures of around $$700^{\circ }\mathrm{C}$$ only. These findings indicate a significant gap between current testing standards and real fire performance of facade systems. A study of failure mechanisms of individual components during the experiments showed the need of considering the system in its entirety rather than performing component level testing. The importance of firestops also became evident through these experiments. Properly designed firestop system ensured good compartmentation and prevented spread of fire to the upper floors, whereas improper firestop allowed fire to spread easily to upper floors. It is expected that the insights presented in this study will be useful to improve facade designs as well as to develop more robust testing procedures.

Large-scale urban conflagrations in informal settlements are a frequent global event, however there is a lack of experimental research and knowledge within literature on how informal settlements fires spread to support local or national intervention strategies. This paper, therefore, presents results and analysis of a full-scale fire spread experiment of a mock 20 dwelling test settlement with a 4 by 5 layout aimed at understanding settlement-scale fire spread behaviour. A “fire line” scenario was created by imultaneously igniting four dwellings in a row, and then allowing the fire to propagate through the settlement to replicate fire disasters involving large numbers of homes. Results highlight the critical hazard posed by the close proximity of neighbouring dwellings (1-2 m), with wind playing a primary role in directing and driving the spread process. Even with a relatively mild wind speed of 15-25 km/h, the fire spread through the entire mock settlement within a mere 5 minutes. Following ignition of a given dwelling, flashover is reached very quickly, with the temperatures reaching more than 1000°C within one minute, and downwind neighbour structures igniting less than a minute thereafter. The results suggest that multi-dwelling effects are not dominant in these types of fires, but may become meaningful at a larger scale when branding and topography play a role. Findings show that on a global scale fire behaviour is analogous to a wildfire with a continuous fire front moving through an area, although individual dwellings still do follow the distinct phases of enclosure fires, except that collapse occurs more rapidly than in formal structures. This experiment represents one of the larger urban fire tests conducted to date, and the largest informal settlement fire experiment.

Structural stability is highly important for the safe evacuation of occupants and safe access to fire-fighters in accidental fire events. In this paper, the effect of fire protection of beams on the fire resistance of heated columns is studied firstly, and the results show that fire protection of beams may have little effect on the behaviours of heated columns as the heating time of fire spread scenario is short in this study. Then, the behaviours of 3D steel frames subjected to seven different fire spread scenarios have been investigated. The effects of fire source location, occurrence time of fire spread, and direction of fire spread on the fire resistance of steel frame are comprehensively studied. In case of horizontal fire spread scenarios with different fire source compartments, collapse occurs when the corner and long edge compartments are fire source compartments. A stable catenary mechanism of beam could improve and control the collapse time and range. The corner column may bear the catenary tensions in two horizontal directions, and the lateral stiffness of corner column should be crucial for the design of structural fire. For the non-insulated steel frame, the maximum temperature and maximum axial force of heated columns appear at same time and collapse finally happens in the scenario that fire spread when the gas temperature of fire source compartment reaches the peak temperature. The time of most adverse spread for the non-insulated steel frame should be that when the gas temperature of fire source compartment reaches the peak temperature. The influence of vertical fire spread on heated columns may be smaller than that of horizontal fire spread, but vertical fire spread had great influence on fire resistance of beam. According to this study, spread range, duration, and fire temperature are the three most critical factors of fire spread, and the adverse horizontal spread scenario could be mainly selected from these factors.

While fire-related injuries and deaths decreased in the global north over the past few years, they have increased in the global south. With more than one billion people residing in informal settlements (sometimes known as slums, ghettos or shantytowns), it is necessary that greater effort be placed on addressing and developing means for improving fire safety in these areas. As a result of advances made in computer technologies, emerging performance-based regulations and an increase in building complexity in the global north, the use of computer models simulating enclosure fires have increased dramatically. In this work an experimental investigation is presented for (a) a full-scale corrugated steel sheeting clad informal dwelling experiment and (b) a full-scale timber clad informal dwelling experiment. The experimental results are then compared to numerical models consisting of both simple two-zone (OZone) and computational fluid dynamic models. Currently, there is negligible literature available on Fire Dynamic Simulator (FDS) modelling of informal settlement dwellings (sometimes known as shacks or shanties) fires. This paper evaluates the plausibility of using FDS v6.7 and zonal models to predict certain fire parameters (i.e. ceiling temperatures, heat fluxes, etc.) for Informal Settlement Dwellings (ISDs) and to study the plausibility of using FDS to estimate the probability of fire spread. In this paper an introduction to ISDs is given with details pertaining to construction materials and considerations needed for numerical modelling of informal dwellings (i.e. thin permeable boundaries or combustible boundaries). Models are based upon (a) a prescribed heat release rate per unit area in FDS using data obtained from a Fire Propagation Apparatus test, and (b) an empirical two-zone model using OZone. The FDS validation guide was used to quantify the model uncertainties in order to give a critical separation distance at which fire spread between dwellings will not occur. It was found that at 3 m spacing between ISDs there is a 6% chance (based on the model uncertainties) that fire spread can occur. This is an important finding that highlights the danger associated with these closely spaced dwellings and the hope is that it can guide local government and Non-Governmental Organizations in future decision making. Three meters spacing between dwellings, however, may not be possible due to the socio-cultural-political-economic issues associated with informal settlements. This is one of the first papers to demonstrate FDS models against full-scale ISD experiments.

Understanding the relationship between fire department response times and fire outcomes is critical for understanding the impact of a fire department in a community . This paper outlines a statistical analysis of United States fire department response times to fires in 1–2 family residential dwellings between the years 2002–2017. Using data from the National Fire Incident Reporting System (NFIRS), it is shown that a log-normal distribution provides a reasonable approximation of the empirical distribution of response times. Furthermore, this paper investigates the effect of increasing response times on several different measures of fire severity, including the reported fire spread category, the estimated monetary property and contents losses, and the reported flame damage. It was found that all averaged measures of fire severity increase over the interval of 3–13 min of response time, which is primarily due to the increased likelihood of very severe fire incidents at longer response times. An analysis was conducted to assess the effect of meeting the first unit response time benchmarks outlined in NFPA 1710 on the severity of fire outcomes in a community. It was found that department response times were most strongly correlated with the fraction of fires that do “extreme” damage to at least one story and the fraction of the property value lost. It has been proposed that a power law distribution is appropriate for modeling the distribution the burned areas in urban fires. In order to assess whether this proposition is supported by United States data, a Monte-Carlo methodology has been developed to estimate the burned area indirectly from NFIRS data. Finally, several methods are presented for evaluating data consistency and quality from the NFIRS reports. One of the major findings of this study is the quantification of the effect of response time on various measures of fire loss.

Theoretical models and empirical analyses have combined to suggest that, for some ranges of climate, alternative stable states in vegetation structure may be possible: positive feedbacks with fire may differentiate savanna from forest, while positive feedbacks with hydrological processes may differentiate grassland from savanna. However, existing models have largely failed to include spatially explicit fire spread, dispersal, and hydrological processes, and as such ignore key features of vegetation systems. In this paper, we incorporate spatial and stochastic effects to form a comprehensive and realistic description of the dynamics of vegetation growth. By using novel computational tools such as path-sampling, we investigate the effect of noise and spatial coupling on the stability and the dynamics of forest-savanna transitions. Spatial effects change model behaviors: We find that spatial interactions between savanna and grassland result in the eventual nucleation and propagation of one of the states to invade the other. Which state wins depends on parameter values, which in turn depend on environmental conditions. Meanwhile, transitions between savanna and forest occur much less frequently, because an event such as a period of fire suppression in savanna or a fire in forest must be larger to successfully invade a landscape; this results in transitions between savanna and forest that, although not strictly history dependent, look temporally similar to hysteresis because the time lags involved in transitions are so large.

Presently, there is a need for a robust numerical simulation approach to investigate the influence of various parameters on fire spread in large open framed structures. CFD-based methods can already be used for analyzing the fire conditions but they are difficult to apply for large calculations where the geometrical details of the fuel are sub-grid scale. In this paper we present a CFD-based fire spread simulation method that makes use of the ignition temperature model for pyrolysis and introduce a correction for the mesh dependency of the fuel surface area. Wood sticks, with an ignition temperature of 300°C and a specified heat release rate per unit area of 260 $$\hbox {kW/m}^2$$ , were used as fire load. The method was validated using laboratory scale tunnel ( $$\hbox {10 m }\times \hbox { 0.6 m }\times \hbox { 0.396 m}$$ ) fire tests with a longitudinal velocity of 0.6 m/s, demonstrating a 3% bias for the peak heat release rates and less than 33% biases for the fire growth rate. The method was then applied to room-scale fire spread simulations with uniformly distributed wood cribs at $$600\,\hbox {MJ/m}^2$$ . The results show that, with the help of the surface area correction, the fine-mesh predictions of the heat release rate and thermal environment can be reproduced with coarser meshes and one order of magnitude lower computational costs. Due to the inherent inability of the large-scale CFD to resolve the flame temperature, there is a minimum size of the initial, prescribed fire area which is required for consistent fire spread predictions. Through this study, the authors attempt to build a reliable CFD modelling approach for fire spread and traveling fires.

Lack of quantitative observations of extent, frequency, and severity of large historical fires constrains awareness of departure of contemporary conditions from those that demonstrated resistance and resilience to frequent fire and recurring drought. Compare historical and contemporary fire and forest conditions for a dry forest landscape with few barriers to fire spread. Quantify differences in (1) historical (1700–1918) and contemporary (1985–2015) fire extent, fire rotation, and stand-replacing fire and (2) historical (1914–1924) and contemporary (2012) forest structure and composition. Data include 85,750-ha tree-ring reconstruction of fire frequency and extent; > 375,000-ha timber inventory following > 78,900-ha fires in 1918; and remotely-sensed maps of contemporary fire effects and forest conditions. Historically, fires > 20,000 ha occurred every 9.5 years; fire rotation was 14.9 years; seven fires > 40,469 ha occurred during extreme drought (PDSI 15 cm dbh exceeded 120 trees/ha on 40,469 ha (minimum size of contemporary “megafires”) during extreme drought. In this frequent-fire landscape, mixed-severity fire historically influenced lodgepole and adjacent forests. Lack of large, frequent, low-severity fires degrades contemporary forest ecosystems.

Post-earthquakes fires are high-consequence events, which may cause extensive damage once occurred. However, their nature has not been fully investigated as they are low-frequency events at the same time. A questionnaire survey was conducted for the fire services that corresponded to post-earthquake fires in their areas of jurisdiction in recent years, and outline data on fires following nine earthquakes was collected. A database containing information on 665 fires following 11 earthquakes in Japan from 1995 to 2017 was constructed by integrating survey data into an existing database of fires following the 1995 Kobe and 2011 Tohoku earthquakes. Through this database, the features of post-earthquake fires were comparatively analyzed from the viewpoint of types and causes of fire, ignition, fire spread in urban areas, firefighting activity, fatalities, and damage to fire safety equipment systems. The result shows that electrical is increasing in proportion in comparison with the earlier earthquakes among several causes of ignition; about 70% of all ignitions following major earthquakes occurred within a day from the shaking; and the average time required for fire engines to discharge water after ignition increased by 8–25 times in comparison with the ordinary cases. Quantitative correlations for the rate of ignition, $$ r $$ , cumulative relative frequency of ignition, $$ f $$ , and virtual travel speed of fire engines, $$ v_{FF} $$ , that can be used for the risk assessment of post-earthquake fires were also developed. This comparative analysis provides a comprehensive perspective on the issues of post-earthquake fires that have formerly been analyzed fragmentally and construct a technical basis for the future studies.

Wildfire evacuation triggers refer to prominent geographic features used in wildfire evacuation practices, and when a fire crosses a feature, an evacuation warning is issued to the communities or firefighters in the path of the fire. The existing wildfire trigger modeling methods consider evacuation time as an input from a decision maker and employ fire spread modeling and GIS to create a trigger buffer around a threatened asset. This paper substantially improves on previous methods by coupling fire and traffic simulation models to set triggers, which allows us to estimate evacuation time using a traffic simulation model rather than relying on expert judgment. Specifically, we propose a three-step method within a spatiotemporal GIS framework to couple these models and to evaluate the value of the generated trigger buffers. The first step uses traffic simulation to estimate the total evacuation time for a threatened community. The second step derives the cumulative probabilities for distinct evacuation times from multiple simulations and generates corresponding probability-based trigger buffers. In the last step, we evaluate the value of the generated buffers by coupling fire and traffic simulation models to examine the spatial configurations of fire perimeters and evacuation traffic. A case study of Julian, California is used to test the proposed method. The results from two evacuation scenarios with different travel demand indicate that a larger trigger buffer (more lead time) will be needed for higher levels of evacuation travel demand. For example, the time required to guarantee that 95% of the evacuating residents arrive at the safe area as a fire approaches a community is estimated at 160 min for one scenario but 292 min if the travel demand is doubled. The resulting framework advances the dynamic representation of evacuation traffic in wildfires and improves our understanding of wildfire evacuation timing and decision making. The paper concludes with a discussion of the strengths and limitations of the proposed method, as well as future research directions.

Accurate prediction of forest fire spread is very essential for minimizing its effects. Although many models have been developed to predict the forest fire spread, all these models require several parameters, sometimes, cannot be obtained in a real time. In this paper, the grey system theory was applied for forest fire spread model developing. By preprocessing and fusing the MODIS remote sensing data, the sequence data of the grey model can be confirmed. After making precision comparison among least square estimation algorithm, least square interpolation algorithm and ER algorithm, forest fire spread GM(1, 1) model was developed with ER algorithm and precision of the model was evaluated at the same time. The results showed that the fitting precision and predicting precision of the model were both high, of which the one-level model made up 50%, the two-level 25% and the model between the one-level and the two-level 25%. The prediction accuracy of forest fire spreading model was tested to meet the requirement of modeling. GM(1, 1) model provided a new approach for the study of forest fire spread simulation.

Inspired by a serious fire accident on the cable-stayed bridge, the characteristics of this type of cable fire were investigated pertinently with experiment. And some important parameters, such as temperature distribution and flame height, were measured. The behaviors of fire growth and fire propagation were analyzed; furthermore, fire spread rate was obtained. Additionally, the effectiveness of fire extinguishing methods used in such cable fires was also examined. The results show that the special cables layout and material composition seriously influenced fire behaviors. When internal steel strands were ignited, the polyethylene material on its surface would melt and drop at high temperature, causing that external burning drops penetrated into the interior, which could gradually ignite the unburned part and flaring up the fire. The HDPE sheath originally as a protected component, once ignited, would generate a large amount of burning molten drops, dramatically promoting the fire development to the underneath cable. As observed in fire extinguishing experiments, dry powder, one method recommended by NFPA, showed a re-ignition phenomenon. By comparison, water, one method deprecated in standard, contrarily brought about good effects in fire extinguishing due to an effective cooling effects for inner steel.

The downslope fire represents a percentage of wildland fireline while the heat transfer mechanism of this process is poorly understood. In this study, the experiments were carried out in a fuel bed of dead pine needles with the slopes of − 30°, − 20°, − 10° and 0° for 0.4 and 0.8 kg/m2 fuel loads. Flame length, flame angle, temperatures over the fuel bed, flow speed at the fuel bed surface, radiation heat flux near the end of the fuel bed were measured. The rate of spread shows a parabolic shape which decreases firstly and then increases from 0° to − 30°. The combustion interface, reconstructed from the temperature histories of two vertical thermocouples, was perpendicular to the fuel bed under all slope conditions for two fuel loads. The measured radiation heat flux is higher at − 30° slope than level ground, which is attributed to higher flame emissivity. A quasi-physical model was developed to describe the heat transfer mechanism of downslope fire spread. The calculation results show that the flame radiation dominated the downslope fire spread process and the combustion zone radiation should not be neglected in the near flame region.

This paper reports results of research to validate a fire behavior model “Wildland Fire Dynamics Simulator” through comparison of laboratory-scale measurements under the oxygen consumption calorimetry principle to several simulation runs of ground fire spreading in a fuel bed under wind. Pine needle ground covers of Pinus halepensis Mill. and Pinus pinaster Ait., two pine species in a specific region in northwest Africa were tested. In order to gain a deeper understanding of forest fire behavior, investigation into the rate of spread, one of the most relevant quantities used in forest fire science, is fundamental. Moreover, the heat release rate of the fire spread for different fuel types and related thermal functions such as radiant, convective and conductive heat transfer through beds of pine needles were quantified. The results can be helpful for the improvement and validation of the computational Fluid Dynamics CFD model and give global information on fire spread under wind on a bed of pine needles.

Traditional models result in low efficiency and poor accuracy when simulating the spread of large-scale forest fires. We constructed an improved model that couples cellular automata with an existing forest fire model to ensure better time accuracy of forest fire spread. Our model considers the impact of time steps on simulation accuracy to provide an optimal time step value. The model was tested using a case study of forest fire spread at Daxing’an Mountain in May 2006. The results show that the optimal time step for the forest fire spread geographic cellular automata simulation algorithm is 1/8 of the time taken for cellular material to be completely combusted. When compared with real fire data from Landsat Thematic Mapper (TM) images, our model was found to have high temporal and spatial consistency, with a mean Kappa coefficient of 0.6352 and mean accuracy of 87.89%. This algorithm can be used to simulate and predict forest fire spread and is also reversible (i.e., it can identify fire source points).

A semi-empirical model was developed which forms shrub geometries from distinct fuel elements (e.g. leaves) and describes flame spread from element to element. Ignition, flame growth and flame decay patterns were based on combustion data of single leaves. Extension of the model to various heating conditions was achieved by scaling the flame growth parameters using physics-based heat transfer models. The resulting model offers a novel approach to examine fire spread and to explicitly describe both distinct fuel elements and fire behavior. This approach balances computational speed and modeling detail while providing a unique perspective into fire spread phenomena. Comparisons of the tuned model to fire spread behavior measured in an open-roofed wind tunnel benchmarked the model’s ability to simulate fire spread in manzanita shrubs.

Fire hazard causes lots of economic loss and personal injuries every year. Many ways are proposed to help people escape quickly from dangerous region. As one key step for fire escaping, the fire escaping system detects fire and dynamically provides escaping route to help people escape from fire scene. With the advanced technique, Wireless Sensor Network (WSN), the fire escaping system is developed to be more promising for fire escaping than before. Most existing fire escaping systems ignore or simplify the dynamics of fire hazard. Thus people’s safety is not guaranteed with fire spreading and growing. This paper designs a new fire spread model based on confidential data created by the powerful simulation system: Fire Dynamics Simulator (FDS). Based on the model, this paper predicts the Available Egress Duration (AED) of all locations in the building. Considering both the length and AED of each escaping route, this paper designs a faSt firE Escaping algorithm (SEE). To evaluate the performance of our approach, this paper conducts experiments on a real WSN platform with TelosB nodes. Experiment results confirm that the fire spread model in this paper can achieve high prediction accuracy. SEE outperforms the existing prediction based approaches by utilizing more AED, so that people can escape with higher probability.

While the wildland–urban interface (WUI) is not a new concept, fires in WUI communities have rapidly expanded in frequency and severity over the past few decades. The number of structures lost per year has increased significantly, due in part to increased development in rural areas, fuel management policies, and climate change, all of which are projected to increase in the future. This two-part review presents an overview of research on the pathways for fire spread in the WUI. Recent involvement of the fire science community in WUI fire research has led to some great advances in knowledge; however, much work is left to be done. While the general pathways for fire spread in the WUI (radiative, flame, and ember exposure) are known, the exposure conditions generated by surrounding wildland fuels, nearby structures or other system-wide factors, and the subsequent response of WUI structures and communities are not well known or well understood. This first part of the review covers the current state of the WUI and existing knowledge on exposure conditions. Recommendations for future research and development are also presented for each part of the review.

Structure ignition by wind-driven firebrand showers is an important fire spread mechanism in large outdoor fires. Experiments were conducted with three common mulch types (shredded hardwood mulch, Japanese Cypress wood chips, and pine bark nuggets) placed adjacent to realistic-scale re-entrant corners. In the first series of experiments, mulch beds were placed adjacent to a re-entrant corner constructed with wood studs and lined with oriented strand board (OSB) as the sheathing. The premise behind conducting experiments with no siding treatments applied was predicated on the notion that bare OSB mulch contact would be a worst-case scenario, and therefore, a wall assembly in the most vulnerable state to mulch ignition. In the second series of experiments, vinyl siding was applied to the re-entrant corner assemblies (wood studs/OSB/moisture barrier/vinyl siding), and the influence of vertical separation distance (102 mm or 203 mm) on wall ignition from adjacent mulch beds was determined. The vertical separation distance was maintained by applying gypsum board to the base of the re-entrant corner. The siding itself did not influence the ignition process for the mulch beds, as the mulch beds were the first to ignite from the firebrand showers. In all experiments, it was observed that firebrands produced smoldering ignition in the mulch beds, this transitioned to flaming ignition, and the re-entrant corner assembly was exposed to the flaming mulch beds. With no siding treatments applied, the flaming mulch beds ignited the re-entrant corner, and ignition was observed to propagate to the back side of re-entrant corner assembly under all wind speeds (6 m/s to 8 m/s). With respect to the re-entrant corners fitted with vinyl siding, the mulch type, vertical separation distance, and wind speed were important parameters as to whether flaming ignition was observed to propagate to the back-side of a re-entrant corner assembly. Mulches clearly pose an ignition hazard to structures in large outdoor fires.

Fires that break out in tsunami inundation areas are collectively referred to as “tsunami-induced fires” in contrast with “seismic-induced fires” which have been conventionally a serious concern in Japan. Scenario of this new fire is basically as follows: (1) combustible objects such as houses are washed away by a tsunami, (2) combustible objects accumulate in tsunami inundation area as debris, (3) debris are ignited by some kind of cause, and (4) fires spread to adjacent debris resulting in conflagration in tsunami inundation area. We have been modeling tsunami-driven combustible objects as the first step towards development of tsunami-induced fire spread simulation. This modeling aims to know how combustible objects accumulate in tsunami inundation area to be the input data to fire models for ignition and fire spread. The proposed model is the extension of the existing model for driftwood by incorporating the debris release model and the effect of debris’s collision with surviving buildings. This model collaborates with the existing numerical simulation of tsunamis and is able to predict the drift and accumulation behavior of individual debris by solving the equation of horizontal translational motion. In this paper, we conducted debris diffusion simulation for Yamada, Iwate prefecture, Japan for model’s validation, where 16 ha of area were affected by tsunami-induced fire spread after the 2011 Great East Japan Earthquake Tsunami. The total number of debris tracked in the simulation was 1,850,560. A constant of proportionality, which determines the severity of force acting on drifting debris due to the collision with onshore surviving buildings, was identified by trial and error to maximize the eventual amount of accumulating debris within the fire-damaged zone. As a result, this maximum amount was predicted to be 4654 tons in the case that the constant is 0.1. Two thirds of the released debris, about 12,000 tons, accumulated onshore at the end of computation, and most of the fire-damaged zone was covered by these debris.

This study aims to develop a series of robust and efficient methodologies, which can be applied to understand and estimate firebrand generation and to evaluate firebrand showers close to a fire front. A field scale high intensity prescribed fire was conducted in the New Jersey Pine Barrens in March 2013. Vegetation was characterised with field and remotely sensed data, fire spread and intensity was characterised and meteorological conditions were monitored before and during the burn. Firebrands were collected from different locations in the forest and analysed for mass and size distribution. The majority were found to be bark slices (more than 70%) with substantial amounts of pine and shrub twigs. Shrub layer consumption was evaluated to supplement the firebrand generation study. Bark consumption was studied by measuring the circumference variation at several heights on each of three different pine trees. The variation was in the same order of magnitude as the bark thickness (1–5 mm). Testing and improving the protocol can facilitate the collection of compatible data in a wide range of ecosystems and fire environments, aiding in the development of solutions to prevent structural ignition at the Wildland Urban Interface.

In Canadian forests, the majority of burned area occurs on a small number of days of extreme fire weather. These days lie within the tail end of the distribution of fire weather, and are often the periods when fire suppression capacity is most challenged. We examined the historic and future frequency of such extreme fire weather events across 16 fire regime zones in the forested regions of Canada from 1970 to the year 2090. Two measurements are used to measure the extreme fire weather events, the 95th percentile of Fire Weather Index (FWI95) and the number of spread days. The annual frequency of fire spread days is modelled to increase 35–400 % by 2050 with the greatest absolute increases occurring in the Boreal Plains of Alberta and Saskatchewan. The largest proportional increase in the number of spread days is modelled to occur in coastal and temperate forests. This large increase in spread days was found despite a modest average increase in FWI95. Our findings suggest that the impact of future climate change in Canadian forests is sufficient to increase the number of days with active fire spread. Fire management agencies in coastal and temperate regions may need to adapt their planning and capacity to deal with proportionally larger changes to their fire weather regime compared to the already high fire management capacity found in drier continental regions.

This article introduces a new wildland fire spread prediction system consisting of the raster-based Discrete Event System Specification Fire model (DEVS-FIRE) and the Advanced Regional Prediction System atmospheric model (ARPS). Fire–atmosphere feedbacks are represented by transferring heat from DEVS-FIRE to ARPS as an externally forced set of surface fluxes and mapping the resulting changes in near-surface wind from ARPS to DEVS-FIRE. A preliminary evaluation of the performance of this coupled model is performed through idealized tests and an examination of the September 2000 Moore Branch Fire; the results conform well with those of other coupled models and are superior to those produced by the uncoupled DEVS-FIRE model, motivating further investigation.

A fire took place in an indoor shooting range in Pusan, Korea, causing 15 deaths and 1 injury. To determine the cause of the fire, field investigation and laboratory analysis were conducted, and the point of ignition was determined through closed-circuit television (CCTV) imagery. Residues of ball powder, balloon, and stray bullet were found at the point of ignition. Moreover, the polyurethane slabs installed for sound absorption on the walls and ceiling surrounding the point of origin were found to lack any flame resistance. In tests of gunpowder ignition on the surface of the sound absorbers, the material ignited readily and the fire spread rapidly. Through analysis of CCTV at the time of ignition, any source of ignition related to human intervention could be ruled out. Considering the fact that ignition started immediately after shooting and the rubber plate for stray bullet protection had fallen off, we conclude that the most probable scenario is that a stray bullet landed on the sound absorber at the point of origin and ignited ball powder accumulated there, thus starting the fire. As a result of shooting 50 rounds of bullets, most bullet fragments dropped within 2 m of the bullet trap whereas two stray bullets reached 4.6 m and 1.3 m from the point of ignition. It was revealed that people at the indoor shooting range did not have sufficient time to evacuate. Although the fire lasted for a short time, victims were exposed to high temperatures, making visual identification difficult.

The Great Valparaiso Fire started as a wildfire on the outskirts of the city. The fire spread through the wildland–urban interface towards the city. In 5 days, it claimed the lives of 15 people, injured more than 500 people, destroyed over 2,900 homes, burned over 1,000 ha, and displaced approximately 12,500 people. In this Letter to the Editor, several issues that facilitated the tragic events are discussed.

The mountain pine beetle (Dendroctonus ponderosae Hopkins; MPB) has killed lodgepole pines (Pinus contorta Dougl. ex Loud.) across 20 million hectares of central British Columbia, Canada, since the late 1990s, challenging land managers as well as fire management personnel. Although recent studies have used models to simulate how MPB might affect fire spread, very little fire behaviour has been documented in MPB-affected stands. We documented rate of spread (ROS) in experimental fires and wildfires in recent MPB-killed stands in British Columbia using interpretations of oblique photographs, airborne measurements of wildfire spread, and experimental burns. Fire spread observations were used to develop ROS models following the empirical approach of the Canadian Forest Fire Danger Rating System (CFFDRS). Sixteen fire runs were examined that occurred in mature MPB-affected pine stands from 1 to 5 years since peak attack. Observations of ROS were associated with corresponding weather measurements from nearby weather stations and non-linear regression curves were fit to paired ROS and Initial Spread Index (ISI) data according to CFFDRS convention. Although the dataset is less robust than a strictly experimental approach, fires had faster spread and more crown fire than predicted, with a linear average of 2.7 times higher ROS in best fit models than expected for unaffected pine. The most likely crown fire initiation threshold (P = 0.5) was ISI 5.5. Fire intensity is likely higher in early post-MPB stands due to increased ROS, lower crowning thresholds, and greater consumption of fine dead branches. Further studies on fire behaviour in MPB-affected stands are needed, but the present findings can help reduce uncertainty in fire and land management decisions in the interim.

The Two-Stage forest fire spread prediction methodology was developed to enhance forest fire evolution forecast by tackling the uncertainty of some environmental conditions. However, there are parameters, such as wind, that present a variation along terrain and time. In such cases, it is necessary to couple forest fire propagation models and complementary models, such as meteorological forecast and wind field models. This multi-model approach improves the accuracy of the predictions by introducing an overhead in the execution time. In this paper, different multi-model approaches are discussed and the results show that the propagation prediction is improved. Exploiting multi-core architectures of current processors, we can reduce the overhead introduced by complementary models.

Since 1980, it has been possible to estimate the size of the fire problem associated with many types of burnable products when those products are the first items ignited. However, many burnable products also have a major role as the largest fuel package in the room and may be the most important fuel package even if not the first item ignited. Only in the last few years have we had enough years of fire data with coding sufficient to support sound estimates of fires where a defined product is the primary fuel but not the first fuel. This article describes a proposed methodology for making those estimates and describes the results of application of the new methodology to upholstered furniture. The application to upholstered furniture demonstrated that one-quarter of upholstered furniture fires, civilian injuries, and direct damages, and one-fifth (21 %) of associated civilian deaths are associated with fires in which upholstered furniture is the primary item contributing to fire or flame spread but not the item first ignited. The traditional focus on cigarette resistance leaves roughly half of the fire deaths from upholstered furniture fires untouched.

Relative to other cities in Japan, Kyoto contains an outstanding agglomeration of historic buildings. These historic buildings are crucial for maintaining Kyoto’s irregular ranking as a historical city. However, several active faults occur near Kyoto that could cause severe seismic damage to the city. Thus, post-earthquake fire is one of the most threatening potential disasters that could destroy Kyoto’s invaluable historic buildings. Here, the post-earthquake fire safety of 2,131 historic buildings in the city of Kyoto was analyzed. This analysis was conducted by Monte Carlo simulation with a physics-based urban fire spread model that was formerly developed by the author. This scenario assumes the three following exclusive events that lead to the burn-down of historic buildings: (I) the ignition in the vicinity of the target historic building; (II) inadequate firefighting activity during the initial stage of the fire; and (III) the occurrence of widespread fire in urban areas following ignition. In general, the post-earthquake fire safety of designated and registered historic buildings was greater than that of undesignated and unregistered historic buildings. In addition, in the worst case scenario, 30% of the national treasures and important cultural properties would be damaged in the center of Kyoto city.

Background An approach to predict fire growth in an operational setting, with the potential to be used as a decision-support tool for fire management, is described and evaluated. The operational use of fire behaviour models has mostly followed a deterministic approach, however, the uncertainty associated with model predictions needs to be quantified and included in wildfire planning and decision-making process during fire suppression activities. We use FARSITE to simulate the growth of a large wildfire. Probabilistic simulations of fire spread are performed, accounting for the uncertainty of some model inputs and parameters. Deterministic simulations were performed for comparison. We also assess the degree to which fire spread modelling and satellite active fire data can be combined, to forecast fire spread during large wildfires events. Results Uncertainty was propagated through the FARSITE fire spread modelling system by randomly defining 100 different combinations of the independent input variables and parameters, and running the correspondent fire spread simulations in order to produce fire spread probability maps. Simulations were initialized with the reported ignition location and with satellite active fires. The probabilistic fire spread predictions show great potential to be used as a fire management tool in an operational setting, providing valuable information regarding the spatial–temporal distribution of burn probabilities. The advantage of probabilistic over deterministic simulations is clear when both are compared. Re-initializing simulations with satellite active fires did not improve simulations as expected. Conclusion This information can be useful to anticipate the growth of wildfires through the landscape with an associated probability of occurrence. The additional information regarding when, where and with what probability the fire might be in the next few hours can ultimately help minimize the negative environmental, social and economic impacts of these fires. Electronic supplementary material The online version of this article (doi:10.1186/s40064-016-2842-9) contains supplementary material, which is available to authorized users.

This study focuses on a new device that can reduce radiation heat at the openings of buildings. Intumescent coating is sprayed on wire netting affixed to the open spaces in the external wall of a building to reduce radiation heat and fire spread. This study uses a 1.2 m × 1.2 m × 1.2 m furnace to conduct fire-resistance tests according to the ISO 834-1 standard (the standard 1 h temperature rise curve and the furnace pressure). The study variables include wire netting with different mesh numbers (mesh widths) and wire netting with different coating thicknesses. The results from six sets of fire tests show that under the same coating thickness, less radiation heat is generated for a larger mesh number (i.e., smaller mesh width). Under the same mesh number for the wire netting, less radiation heat is generated for a larger coating thickness. At distances of 50 cm, 100 cm, and 150 cm from a fire source with a temperature of 945°C, the radiation heat calculated based on the theory is 6.9 W/cm2. This study proves that the radiation heat can be dropped to 0.48 W/cm2 with the installation of intumescent-coated wire netting, and that this type of netting can effectively prevent fire spreading by radiation.

This study examines the size distribution and other characteristics of firebrand exposure during the 2007 Angora fire, a severe wildland–urban interface fire in California. Of the 401 houses that received direct interface fire exposure 61% were destroyed and 30% did not burn at all. The ignition of buildings by wind-driven firebrand showers and the starting of “spot fires” in unburned vegetation ahead of wildfires have been observed for some time. Empirically quantifying the exposure severity or describing how many firebrands of what size and over what duration and distance cause ignition problems of concern has not yet been possible. However, a unique opportunity to gather empirical firebrand data from an actual interface fire evolved in the days immediately following the Angora fire. Digital analyses of burn patterns from materials exposed to the Angora fire were conducted to determine firebrand size distributions. It is probable that some burn patterns were larger in area than the firebrands due to progressive combustion or melting, but it was assumed that the overall size distributions of burn pattern areas were representative of actual firebrand sizes. This assumption was investigated by exposing sections of materials collected in the Angora fire to wind driven firebrands generated in the laboratory using the unique NIST Dragon’s lofting and ignition research facility (NIST Dragon’s LAIR facility). The firebrand size distributions reported were compared to firebrand size distributions from experimental firebrand generation in both recent laboratory building ignition studies conducted by NIST and from historical firebrand field studies. Such data is needed to form the basis of effective and appropriate interface fire hazard mitigation measures as well as modeling fire spread. Comparisons are made to current wildfire protection building construction regulations and test standards. The most salient result of this study is documentation of the consistently small size of firebrands and the close correlation of these results with the sizes of experimentally generated firebrands.

The interaction of fires, where one fire burns into another recently burned area, is receiving increased attention from scientists and land managers wishing to describe the role of fire scars in affecting landscape pattern and future fire spread. Here, we quantify fire-on-fire interactions in terms of frequency, size, and time-since-previous fire (TSPF) in three large wilderness areas in Montana and Idaho, USA, from 1984 to present, using spatially consistent large fire perimeter data from the Monitoring Trends in Burn Severity (MTBS) dataset. The analysis is supplemented with less consistent fire perimeter data from a regional fire atlas in order to examine the potential role played by smaller fires in fire-on-fire interactions. We compare current rates of burning to existing estimates using the natural fire rotation (NFR) to determine whether recent fire activity falls within established historical ranges. We also compare actual fires to randomly located fires to establish whether the frequency and size of re-burns differ by chance. Finally, we systematically classify shared fire edges as fire-stopping or breached to quantify the effect of previous fires on subsequent fire spread. In total, more than half of the Frank Church, one-quarter of the Bob Marshall, and fifteen percent of the Selway-Bitterroot wilderness areas have burned since 1984. Area burned within each of the study areas yielded NFRs that are consistent with results derived from fire atlas and tree-ring research studies. The data show that re-burning occurs less frequently than chance in the Frank Church Wilderness Area, perhaps less frequently in the Bob Marshall Wilderness Area, and the same as chance in the Selway-Bitterroot Wilderness Area. In each of the study areas, the total amount of edge at which a fire met another fire was less than three percent of the total available perimeter. However, ∼80 % of the total edge encountered was breached, resulting in fire spreading onto previously burned landscapes and re-burning at least 40 ha. Year-to-year variability in re-burn occurrence was high, and the size of re-burns was typically small, implying a general resistance to re-burning, but the preponderance of small patches resulting from fire interactions has perhaps significant ecological implications. There was a systematic decrease in the frequency of small to medium sized re-burns (40 ha to 405 ha) as time between fires increased in all three wilderness areas. The frequency of large re-burns increased with time in the Frank Church wilderness area, but this trend was not apparent in the other two wilderness areas. Overall, fire-on-fire interactions show a high degree of complexity, making direct comparisons between the three wilderness areas difficult, but the evidence suggests that large wildfires generally inhibit the spread of subsequent fires, while small fires appear to have little impact on the spread of other fires. The limiting effect of large fires on small fires is potentially significant based on the number of cases observed (n = 101).

Rapid urban sprawl and population decentralization in recent decades have increased the size of the wildland-urban interface and resulted in higher community risk and vulnerability to wildfire. This paper primarily focuses on understanding grass-fueled fires common to Texas and improving the understanding of the physics and fire dynamics that are inherent in the grassland and prairie flame spread problem. Little bluestem (Schizachyrium scoparium) grass was chosen as the grassland fuel due to its prevalent coverage in the Texas area and its relevance to grassland fires in Texas. The methodology in this study relies on a framework to characterize fuel properties of little bluestem grass using small- and intermediate-scale experiments to better predict full-scale fire behavior. An intermediate-scale numerical flame spread model was developed for grass fuels that accounts for fuel moisture content to calculate the mass versus time of a burning little bluestem plant. The results of the small- and intermediate-scale experiments were used to develop input parameters for a field-scale numerical simulation of a grass field using a physics-based computational fire model, Wildland-urban interface Fire Dynamics Simulator (WFDS). A sensitivity analysis was performed to determine the effect of varying WFDS input parameters on the fire spread rate. The results indicate that the fuel moisture content had the most significant impact on the fire spread rate.

This study reported an actual building fire incidence for a ten-story building that occurred in Taiwan in 2008. Due to the stack effects the fire occurred on the third floor spread through the patio in a short time to the upper floors and caused three deaths in a tenth floor apartment. This study also attempted to reconstruct the actual fire scenario using computer simulation. The spread of the fire to the combustibles due to hot smoke was accounted for in the simulation. Variation of the fire scenario and the factors causing the fire spread were studied. It was found that an initial fire size below 1.0 MW would not generate sufficient hot smoke to cause fire spread despite the stack effects. However, any obstructions in the patio such as window shading has been found to cause heat accumulation that would aggravate the fire spread problem. The presence of a canopy at the top of the patio can cause higher concentration of smoke for the upper floors. The simulation results are found to be in good agreement with the actual incidence. Moreover the simulation results also show that when the fire spread through the patio the initial fire size of 1.0 MW at the fire site can grow to a building fire of 300 MW.

Concerns exist both in New Zealand and internationally about the performance in fire of insulated panel, particularly relating to the combustibility of polymer foam core materials. The focus of this paper is the most commonly used panel product in New Zealand, polystyrene insulated panel (PIP), with its core of expanded polystyrene. A series of experimental research projects were conducted to investigate the fire performance of the material. The objective of the research programme was to quantify the fire performance, using oxygen depletion calorimetry, of different construction details. In addition, laboratory experiments also investigated the influence of fire retardant treatment and the issue of fire spread in panel cavities. The major conclusion of the research was that maintaining the integrity of the metal skins of PIP had a quantifiable and significant beneficial impact on the fire performance of PIP.

Mass fire-spread is a potential threat to some densely built urban areas by its devastating destructions. Especially in case of a large earthquake when multiple fires break out simultaneously, fire-spread hazard is likely to overwhelm fire-fighting capabilities and enlarge damage area. To explore fire-spread behavior and assess its damages, a simulation model of fire-spread in densely built urban areas is developed. Cellular Automata (CA) is a Bottom-up dynamics model that can reproduce a complicated phenomenon by setting up simple rules in a cell space. However, the traditional grid-based cells of CA are not suitable for modeling building-to-building fire-spread behavior. Therefore, an irregular coarse CA schema is proposed in this paper. Two sub-processes are involved urban mass fire-spread, i.e. (I) fire-developing in a single building and (II) fire-spread among buildings. When a fire is developing in a single building, the building will experience 5 fire stages along time, which become the states of cell. While fire spreads among buildings, there are 2 spread patterns: (I) short-range direct flame contact, radiation and convection spread and (II) long-range firebrand spotting spread. In relation to the 2 spread patterns, 2 sets of neighborhoods and rules of CA are formulated respectively. To verify the newly developed model, 100 times of individual random simulations for a real site fire-spread in Kobe City after Hanshin Earthquake (1995, Japan) are performed using an integrated GIS-CA-fire tool developed in the paper. Comparing the simulation results with the local observations, the general feature of fire-spread is found similar, and it is proved that the newly developed model is reliable to simulate urban fire-spread. Furthermore, based on the simulated results, a loss assessment model is formulated to calculate economic and life losses after fire-spread.