Fire

Smoke detection is crucial for early fire prevention and the protection of lives and property. Unlike generic object detection, smoke detection faces unique challenges due to smoke’s semitransparent, fluid nature, which often leads to false positives in complex backgrounds and missed detections—particularly around smoke edges and small targets. Moreover, high computational overhead further restricts real-world deployment. To tackle these issues, we propose RT-DETR-Smoke, a specialized real-time transformer-based smoke-detection framework. First, we designed a high-efficiency hybrid encoder that combines convolutional and Transformer features, thus reducing computational cost while preserving crucial smoke details. We then incorporated an uncertainty-minimization strategy to dynamically select the most confident detection queries, further improving detection accuracy in challenging scenarios. Next, to alleviate the common issue of blurred or incomplete smoke boundaries, we introduced a coordinate attention mechanism, which enhances spatial-feature fusion and refines smoke-edge localization. Finally, we propose the WShapeIoU loss function to accelerate model convergence and boost the precision of the bounding-box regression for multiscale smoke targets under diverse environmental conditions. As evaluated on our custom smoke dataset, RT-DETR-Smoke achieves a remarkable 87.75% mAP@0.5 and processes images at 445.50 FPS, significantly outperforming existing methods in both accuracy and speed. These results underscore the potential of RT-DETR-Smoke for practical deployment in early fire-warning and smoke-monitoring systems. Full article

As an emerging development field, in recent years, emergency industrial parks in China have faced increasingly complex and high-risk challenges. This article proposes the establishment of a scientific safety risk assessment and grading model to help improve the safety management level of emergency industrial parks, in response to the problems of the multi-source heterogeneity of fire risks in emergency industrial parks and the difficulty of comprehensive assessment using traditional methods. This approach combines enterprise type classification with multi-level assessment for the first time, effectively identifying high-risk links such as fires and explosions and playing an effective role in preventing accidents such as fires in the park. Enterprises within the park are categorized into seven distinct groups based on their characteristics and associated safety risks: medical and healthcare, new energy storage, composite materials and new materials, intelligent manufacturing, mechanical manufacturing, consulting and technical services, and construction and installation. The following models are constructed: (1) a risk assessment model based on AHP-FCE, which can assess the safety risk levels of individual enterprises and the industrial park at a macro level; (2) a risk grading model based on the risk matrix method, which can inspect and control specific risk sources at a micro level. The integration of these two methods establishes a comprehensive model for safety risk assessment and grading in emergency industrial parks, significantly improving both the accuracy and the systematic nature of risk management processes. Full article

Both single-skin and double-skin glass facades are extensively employed in commercial high-rise buildings and are gaining increasing popularity. However, the capability to deploy firefighting agents in such ultra-high structures remains limited and has been minimally investigated. To provide guidance for single-layer exterior wall fire protection, this study examines the impact of vertical walls on window ejected plumes by simulating the upper portion of jet plumes using a square burner flame. Experimental and numerical simulations were conducted. The findings revealed that plumes from propane burners could attach to the wall even when L_{E. burner fire} > 0.7W, contradicting previous criteria. This discrepancy arises because prior studies underestimated the induced pressure difference in large fires. This pressure difference propels the plume toward the wall, behaving like a rigid body. Full article

Wildfire activity in the western United States has been on the rise since the mid-1980s, with longer, higher-risk fire seasons projected for the future. Prescribed burning mitigates the risk of extreme wildfire events, but such treatments are currently underutilized. Fire managers have cited lack of firefighter availability as a key barrier to prescribed burning. We use both principal component analysis (PCA) and logistic regression modeling methodologies to investigate whether or not (and if yes, under what conditions) personnel shortages on a given day are associated with lower odds of a prescribed burn occurring in the Okanogan–Wenatchee National Forest. We utilize the logit model to further assess how personnel availability compares to other potential barriers (e.g., meteorological conditions) in terms of association with odds of a prescribed burn occurring. Our analysis finds that fall and spring days in general have distinct constellations of characteristics. Unavailability of personnel is associated with lower odds of prescribed burning in the fall season, controlling for meteorological conditions. However, in the spring, only fuel moisture is observed to be associated with the odds of prescribed burning. Our findings suggest that if agencies aim to increase prescribed burning to mitigate wildfire risk, workforce decisions should prioritize firefighter availability in the fall. Full article

With increasing wildfire severity and duration driven by climate change, accurately predicting fire behavior over extended time frames is critical for effective management and mitigation of such wildfires. Fire propagation models play a pivotal role in these efforts, providing simulations that can be used to strategize and respond to active fires. This study examines the fire area simulator (FARSITE) model’s performance in simulating recent wildfire events that persisted over 24 h with limited firefighting intervention in mostly remote access areas across diverse ecosystems. Our findings reveal key insights into a prolonged wildfire scenarios potentially informing improvements in operational fire management and long-term predictive accuracy, as the area comparisons indexes showed reasonable results between the detected fires from the fire information for resource management systems (FIRMSs) in the first 24 h of the fire and the following days. A case study of a recent wildfire in Madeira Island highlights the integration of real-time weather predictions and post-event weather data analysis. This analysis underscores the potential of combining accurate forecasts with retrospective validation to improve predictive capabilities in dynamic fire environments, which guided the development of a software platform designed to analyse ongoing wildfire events in real-time, leveraging image satellite data and weather predictions. Full article

Fires pose significant threats to human safety, health, and property. Traditional methods, with their inefficient use of features, struggle to meet the demands of fire detection. You Only Look Once (YOLO), as an efficient deep learning object detection framework, can rapidly locate and identify fire and smoke objects in visual images. However, research utilizing the latest YOLO11 for fire and smoke detection remains sparse, and addressing the scale variability of fire and smoke objects as well as the practicality of detection models continues to be a research focus. This study first compares YOLO11 with classic models in the YOLO series to analyze its advantages in fire and smoke detection tasks. Then, to tackle the challenges of scale variability and model practicality, we propose a Multi-Scale Convolutional Attention (MSCA) mechanism, integrating it into YOLO11 to create YOLO11s-MSCA. Experimental results show that YOLO11 outperforms other YOLO models by balancing accuracy, speed, and practicality. The YOLO11s-MSCA model performs exceptionally well on the D-Fire dataset, improving overall detection accuracy by 2.6% and smoke recognition accuracy by 2.8%. The model demonstrates a stronger ability to identify small fire and smoke objects. Although challenges remain in handling occluded targets and complex backgrounds, the model exhibits strong robustness and generalization capabilities, maintaining efficient detection performance in complicated environments. Full article

In order to study the characteristics of the thermal runaway process of a full-size prefabricated cabin energy storage system, a full-scale prefabricated cabin energy storage physical fire test platform was designed using 100% SOC energy storage battery packs as the thermal runaway object, and full-scale prefabricated cabin energy storage system physical fire experiments were conducted. This experiment analyzes the early change rules of parameters such as temperature, voltage, CO, and VOC after the energy storage system enters thermal runaway and explores the technical methods to improve the fire protection of electrochemical energy storage systems. The results show that the time when the surface temperature of the runaway cell undergoes a sudden change is 37 s later than the time when the voltage undergoes a sudden change; the CO at the bottom and middle of the runaway cluster reaches the alarm threshold 25 s and 39 s earlier than that at the top of the cluster, respectively, and the peak concentration of CO at the bottom and middle of the cluster is more than three times that at the top of the cluster. The opening of the fan causes the CO concentration on the left side of the thermal runaway cluster to be higher than that of the runaway cluster; before the battery thermal runaway, the VOC concentration at the middle and top of the runaway cluster is generally higher than that at the bottom of the cluster. After thermal runaway occurs, the VOC concentration at the bottom of the thermal runaway cluster exceeds that at other positions of the runaway cluster and the adjacent cluster; the t_VOC at the top, middle, and bottom of the thermal runaway cluster is 2296 s, 1681 s, and 1464 s earlier than the t_CO, respectively, but the initial detection value of VOC fluctuates more than that of CO. Full article

Wildfires in the Mediterranean basin, particularly in Portugal, pose significant ecological challenges by altering landscapes and ecosystems. This study examines vegetation recovery in Serra do Açor seven years after the 2017 wildfires, using remote sensing and field data to analyze post-fire dynamics. The primary goal was to assess whether fire severity, measured via the dNBR index from Sentinel-2 imagery, impacts vegetation recovery or if site-specific factors and pre-fire floristic composition are more influential. Randomly assigned plots based on previous land use and fire severity were analyzed for floristic attributes. To quantify and classify cover changes, a supervised classification methodology based on the random forest algorithm was applied to Sentinel-2 data. The results showed no clear link between fire severity and recovery; instead, local factors like soil and topography, along with dominant pre-fire species, influenced recovery. Acacia and eucalyptus communities grew faster and increased the occupied area but exhibited lower diversity than native vegetation communities. Supervised classifications achieved high accuracy (Kappa > 0.90), showing increased shrubland areas and expansion of eucalyptus and acacia. The study highlights the methodology’s effectiveness and potential for broader applications in future research. Full article

Small-scale model experiments were conducted to examine the effectiveness of a point smoke exhaust system in an asymmetrical V-shaped tunnel. Using a design fire power of 20 MW as a reference, the study explored the optimal smoke exhaust rate for the point exhaust system in tunnels. Additionally, the impact of different slope combinations and various smoke vent opening configurations on the smoke control efficiency was analyzed when the fire source was positioned at the slope transition point of the V-shaped tunnel. The results indicate that an exhaust rate of approximately 140–160 m³/s is effective in controlling smoke for a 20 MW fire. In V-shaped tunnels, when three exhaust vents are symmetrically opened on both sides of the fire source, smoke diffusion on the large slope side remains uncontrolled. To address this issue, increasing the number of smoke exhaust vents on the large slope side can enhance smoke control. However, when the slope difference between the two sides of an asymmetrical V-shaped tunnel is excessively large—especially when the large side has a very high inclination—effective smoke control becomes significantly more challenging. Full article

Effective evacuation is vital for minimizing casualties during disasters. This study employed the Web of Science (WOS) database to perform a bibliometric analysis of the evacuation literature. VOSViewer (v1.6.20) and CiteSpace (v6.3.R1) software were used to visualize publication trends, international collaboration networks, keyword co-occurrence, clustering, and keyword bursts. The findings indicate that three research focuses are foundational to advancing the field of evacuation research, with shifts in these areas reflecting the dynamic nature of the field’s transition. Four key research themes outline the core content of the field’s investigation. Furthermore, this study identifies three key research phases in evacuation: the theoretical model development and foundational research phase, the behavioral dynamics and advanced simulation phase, and the data-driven intelligence and practical application phase. Future directions of evacuation research are discussed. This study provides a comprehensive analytical framework that deepens the understanding of the evacuation field. Full article

Wildfires, a natural part of the wildland life cycle, are experiencing a decades-long trend of increased frequency, duration, and magnitude, resulting in increased risk of fatalities and property damage. Fire suppression methods are adapting accordingly, including the increased use of aerial firefighting. Aerial firefighting, conducted in coordination with ground crews, provides real-time reconnaissance of a wildfire and performs strategic drops of retardant to contain and/or suppress the fire. These flight operations require airport and air traffic control infrastructure. The purpose of this report is to provide statistics on the U.S. aerial firefighting fleet, flight operations, and airport utilization and equipment in 2024. This information, which is not readily available, may be of use to airport planners, air navigation service providers, and policy makers. Thirty-four (34) Very Large/Large Air Tankers (VLAT/LATs) were under contract with the United States Forest Service (USFS) Multiple Award Task Order Contracts (MATOCs) in 2024. The aircraft, ranging in age from 27 to 57 years, performed 11,219 retardant drop and reposition flights. Flights operated on 88% of the days with an average of 35 flights per day and a maximum of 200 flights per day. The number of flights per aircraft across the fleet was not uniform (average 288 flights, max 465 flights). Consistent with firefighting practices, the flights operated under Visual Flight Rules (VFR), mostly in the afternoons, with an average retardant drop flight duration of 34 min. Two hundred and seven (207) airports supported at least one departure, with 14 airports supporting 50% of the departures. Eighty-six (86%) percent of the airports were towered and 84% had precision approach procedures. All but two military airports were public airports that are part of the National Plan for Integrated Airport System (NPIAS) and eligible for Airport Improvement Plan (AIP) funding. Runway length and weight bearing are limitations at several airports. Furthermore, operations are no longer limited to airports west of the Rockies, with increased operations in the mid-west and east coast. Full article

Battery electric buses (BEBs) are widely regarded as a safe and sustainable alternative to internal combustion vehicles. However, the lithium-ion batteries that power them present safety risks. This paper provides a comprehensive overview of the safety of battery electric buses, highlighting current challenges, relevant regulations and proposed solutions to enhance safety. There are significant shortcomings in the fire safety regulations for buses, especially concerning qualification methods for bus interiors. Enclosed spaces and structures represent the most critical risks for these transport systems. The presence of large vehicles, such as BEBs, in tunnels could increase the risk of transitioning from deflagration to detonation. Fires involving such vehicles produce more soot than fires from internal combustion engine buses (ICEBs) and have slightly higher toxicity levels. High-pressure water spraying systems are not yet an effective solution, as not all the heat is removed if the thermal runaway has already been triggered for several minutes, and their action remains largely limited to the outside of the battery pack. Another critical issue is cybersecurity. Managing and protecting BEBs from cyber threats is complex and requires robust strategies. Full article

The objective of this study was to understand the characteristics of gas migration in a mine system network domain during a period of reversal ventilation. Combining field experiments with the TF1M3D simulation program, we analyzed gas migration and distribution during reversal ventilation in the JIU LI coal mine. The results showed that, after implementation of the airflow reversal process for the entire mine, the gas in the return roadways flowed back to the working face and accumulated with the gas emitted from the working face to form a gas concentration peak, after which the gas concentration gradually decreased in a stepwise manner and finally reached a stable state that was maintained until the end of the reversal ventilation. The peak gas concentration and the peak areas of the gas concentration curve during the airflow reversal were positively correlated with the time of airflow stoppage operation. The gas concentration peak affected the safety of the mine airflow reversal process; therefore, countermeasures and technical plans should be made in advance. The TF1M3D simulation results were consistent with the field experiment results. Full article

Polylactic acid (PLA) is a biodegradable polymer served as thermal management material, and the heat transfer performance is closely related to its pore structure theoretically, but it is unclear how the structure affects its heat transfer. Therefore, a novel approach is proposed to address this issue by numerical simulations at low complexity and cost; three series of porous PLA are investigated with various structures in pore shape, size, and interval by fire dynamic simulation (FDS) and theoretical modeling, respectively. Meanwhile, the relationship between the hole structure and heat release rate (HRR) is developed by defining a new characteristic shape factor (Sc). It demonstrates that adjusting the pore structure of PLA significantly alters its heat transfer, evidenced by significant variations in HRR and smoke density. Additively, the approach for evaluating heat transfer is elucidated, encompassing the hole closure, vortex heat dissipation effect, and narrow variable speed effect. It provides some theoretical basis for designing porous thermal management materials. Full article

This study aims to evaluate the effectiveness of helicopters in fighting forest fires in Türkiye. The increasing frequency and severity of forest fires, especially with climate change, require more effective aerial response methods. Helicopters play a critical role due to their operational advantages, such as maneuverability, rapid access, and water-carrying capacity. In this study, the types of helicopters used in Türkiye are analyzed, and their operational efficiency is evaluated using Data Envelopment Analysis (DEA). The results reveal that certain models show high efficiency, but some helicopters have room for improvement in terms of fuel consumption and technical performance. A balanced use of both Bambi Bucket and internal water tank systems in fighting forest fires in Türkiye and investing in domestic production is recommended. Full article

Fire has been proven to threaten human lives and buildings significantly. Extensive research is being conducted globally to reduce fire risks, particularly in high-rise buildings that incorporate steel for structural support, timber for decorative elements, and cladding for insulation. Traditional passive fireproofing materials, such as concrete coverings, gypsum boards, and cementitious coatings, often lack aesthetic appeal. Intumescent coatings offer a promising solution to this issue. These coatings require a thin layer on the substrate to protect from fire, and the thin layer expands up to many times its original thickness when exposed to fire, forming an insulating char that acts as a barrier between fire and the substrate. This barrier prevents the steel from reaching critical temperature and helps maintain its integrity during a fire incident. Hence, intumescent coatings are a great choice for passive fire protection of load-bearing steel, wooden structures, timber, and cementitious buildings. Although some research articles discuss intumescent coating types, application methods, fabrication processes, cost-effectiveness, bonding performance, toxicity, and various uses, a comprehensive study encompassing all these topics still needs to be conducted. This review paper explores different types of intumescent coatings, their formulation and manufacturing methods, their application processes, and their use on various substrates. It also covers the key intumescent coating materials and their interactions during fire. Challenges and issues, such as fire protection time, char-forming temperature, and toxicity, are discussed. Full article

With the development of society and the advancement of technology, the application of electricity in modern life has become increasingly widespread. However, the risk of electrical fires has also significantly increased. This paper thoroughly investigates the causes, classifications, and challenges of electrical fires in special environments, and summarizes advanced detection and extinguishing technologies. The study reveals that the causes of electrical fires are complex and diverse, including equipment aging, improper installation, short circuits, and overloading. In special environments such as submarines, surface vessels, and aircraft, the risk of electrical fires is higher due to limited space, dense equipment, and difficult rescue operations. This paper also provides a detailed analysis of various types of electrical fires, including cable fires, electrical cabinet fires, transformer fires, battery fires, data center fires, and residential fires, and discusses their characteristics and prevention and control technologies. In terms of detection technology, this paper summarizes the progress of technologies such as arc detection, video detection, and infrared thermography, and emphasizes the importance of selecting appropriate technologies based on specific environments. Regarding extinguishing technologies, this paper discusses various means of extinguishing, such as foam extinguishing agents, dry powder extinguishing agents, and fine water mist technology, and highlights their advantages, disadvantages, and applicable scenarios. Finally, this paper identifies the limitations in the current field of electrical fire prevention and control, emphasizes the importance of interdisciplinary research and the development of advanced risk assessment models, and outlines future research directions. Full article

This study investigates the physical interactions and between forest fires and the atmosphere, which often lead to conditions favourable to instability and the formation of pyrocumulus (PyCu). Using the coupled atmosphere–fire spread modelling framework, WRF-SFIRE, the Portuguese October 2017 Quiaios wildfire, in association with tropical cyclone Ophelia, was simulated. Fire spread was imposed via burnt area data, and the fire’s influence on the vertical and surface atmosphere was analysed. Simulated local atmospheric conditions were influenced by warm and dry air advection near the surface, and moist air in mid to high levels, displaying an inverted “V” profile in thermodynamic diagrams. These conditions created a near-neutrally unstable atmospheric layer in the first 3000 m, associated with a low-level jet above 1000 m. Results showed that vertical wind shear tilted the plume, resulting in an intermittent, high-based, shallow pyroconvection, in a zero convective available potential energy environment (CAPE). Lifted parcels from the fire lost their buoyancy shortly after condensation, and the presence of PyCu was governed by the energy output from the fire and its updrafts. Clouds formed above the lifted condensation level (LCL) as moisture fluxes from the surface and released from combustion were lifted along the fire plume. Clouds were primarily composed of liquid water (1 g/kg) with smaller traces of ice, graupel, and snow (up to 0.15 g/kg). The representation of pyroconvective dynamics via coupled models is the cornerstone of understanding the phenomena and field applications as the computation capability increases and provides firefighters with real time extreme fire conditions or predicting ahead of time. Full article

Due to the high saturated vapor pressure of low-boiling-point flammable liquids, it is difficult to make fire extinguishers for storage tanks containing them. Air foam extinguishing technology has been recommended by several standards. However, the effectiveness of air foam against low-boiling-point flammable liquid is still limited due to a lack of experimental data. To validate the reliability of air foam, fire-extinguishing measures for three low-boiling-point flammable liquids including propylene oxide, n-pentane, and condensate oil were carried out for the first time in this work. The results show that air foam fails the fire extinguishment of the studied liquids even at higher supply intensities. To address the challenge of fire extinguishment in storage tanks containing low-boiling-point flammable liquids, a novel method using heptafluoropropane (HFC227ea) phase change foaming to substitute air was proposed in this work. The experimental system of HFC227ea foam fire extinguishment was constructed. In addition, two low-boiling-point flammable liquids propylene oxide and n-pentane were selected as the research subjects, the fire extinguishment measures were conducted. The results show that the proposed method can realize rapid and effective extinguishment of flames for the studied liquids. Full article