Search Results (57)

This study presents the design and validation of an integrated fire safety system that leverages edge AI, hybrid sensing, and precision suppression to overcome the latency and collateral limitations of conventional smoke detection and sprinkler systems. The proposed platform features a dual-mode sensor array for early fire recognition, motorized ventilation units for rapid smoke extraction, and a 360° directional nozzle for targeted agent discharge using a residue-free clean extinguishing agent. Experimental trials demonstrated an average fire detection time of 5.8 s and complete flame suppression within 13.2 s, with 90% smoke clearance achieved in under 95 s. No false positives were recorded during non-fire simulations, and the system remained fully functional under simulated cloud communication failure, confirming its edge-resilient architecture. A probabilistic risk analysis based on ISO 31000 and NFPA 551 frameworks showed risk reductions of 75.6% in life safety, 58.0% in property damage, and 67.1% in business disruption. The system achieved a composite risk reduction of approximately 73%, shifting the operational risk level into the ALARP region. These findings demonstrate the system’s capacity to provide proactive, energy-efficient, and spatially targeted fire response suitable for high-value infrastructure. The modular design and SmartThings Edge integration further support scalable deployment and real-time system intelligence, establishing a strong foundation for future adaptive fire protection frameworks. Full article

When lithium-ion batteries experience thermal runaway, a large amount of heat rapidly accumulates inside, causing the internal pressure to rise sharply. Once the pressure exceeds the battery’s safety valve design capacity, the valve activates and releases flammable gas. If ignited in a high-temperature environment, the escaping gas can cause a jet fire containing high-temperature substances. Effectively controlling the internal temperature of the jet fire, especially rapidly cooling the core area of the flame during the jet process, is important to prevent the spread of lithium-ion battery fires. Therefore, this work proposes a strategy of a synergistic effect using microcapsule fire extinguishing agents and fine water mist to achieve an external barrier and an internal attack. The microcapsule fire extinguishing agents are prepared by using melamine–urea–formaldehyde resin as the shell and 1,1,1,2,2,3,3,4,4-nonafluoro-4-methoxybutane (C₅H₃F₉O) and 1,1,2,2,3,3,4-heptafluorocyclopentane (C₅H₃F₇) as the composite core. During the process of lithium-ion battery thermal runaway, the microcapsule fire extinguishing agents can enter the inner area of the jet fire under the protection of the fine water mist. The microcapsule shell ruptures at 100 °C, releasing the highly effective composite fire suppressant core inside the jet fire. The fine water mist significantly blocks the transfer of thermal radiation, inhibiting the spread of the fire. Compared to the suppression with fine water mist only, the time required to reduce the battery temperature from the peak value to a low temperature is reduced by 66 s and the peak temperature of the high-temperature substances above the battery is reduced by 228.2 °C. The propagation of the thermal runaway is suppressed, and no thermal runaway of other batteries around the faulty unit will occur. This synergistic suppression strategy of fine water mist and microcapsule fire extinguishing agent (FWM@M) effectively reduces the adverse effects of jet fires on the propagation of thermal runaway (TR) of lithium-ion batteries, providing a new solution for efficiently extinguishing lithium-ion battery fires. Full article

The ability of a fire extinguisher to suppress fires varies by the rated performance of the unit. Safety guidance in the United States indicates that the occupant should consider the performance rating of the extinguisher when deciding to use it with a fire. The present study investigated whether individuals are aware of the connection between the suppression performance of fire extinguishers and the intensity of fires the unit can extinguish. Across five experiments, participants were presented with fire extinguishers that varied in suppression performance (smaller, medium, and larger) and judged whether the extinguisher could extinguish a developing room fire that increased in intensity. The fire intensity at which they stopped attempting to use the extinguisher (threshold) was calculated. No significant differences in threshold were observed by suppression performance condition when suppression information about the single extinguisher at hand was presented. This included when information was provided about the amount of agent, the distance and duration of discharge, and with the water equivalent the extinguisher was rated. However, when trained on the differences in suppression performance between extinguishers and provided with corresponding containers of water, thresholds did vary by performance rating. We discuss how providing information about variations in suppression performance may be necessary to highlight differences in extinguisher ratings. Full article

Fire blight, a devastating bacterial disease caused by Erwinia amylovora, has posed significant challenges to apple and pear production for over a century. This study introduces a gliding filamentous bacterium, the strain NSD29, isolated from natural forest soil in Xinjiang, China, as a biological control agent for managing this disease. Comprehensive characterization based on morphological, physiological, biochemical, 16S rRNA gene, and whole-genome analyses identified the strain NSD29 as Herpetosiphon llansteffanensis. The train NSD29 demonstrated potent predatory activity against E. amylovora in vitro. Its biocontrol efficacy was subsequently evaluated on detached leaves, inflorescences, young fruit, and shoots of fragrant pear under controlled greenhouse conditions. Results indicated that applying H. llansteffanensis NSD29 significantly inhibited lesion expansion on pear leaves and young fruit, achieving protective efficacies of 75.2% and 72.0%, respectively. Furthermore, pre-treatment spraying with NSD29 effectively reduced the incidence of blossom blight, with a control efficacy of 61.2%. On detached pear shoots, the application of NSD29 fermentation broth suppressed lesion expansion, demonstrating substantial protective (86.8%) and curative (75.6%) efficacies. This research provides the first evidence for the potential of Herpetosiphon species in the biological control of plant diseases, highlighting H. llansteffanensis NSD29 as a promising candidate for developing strategies to combat fire blight. Full article

It is well known that the safety concerns surrounding lithium-ion batteries (LIBs), such as fire and explosion, are currently a bottleneck problem for the large-scale usage of energy storage power stations. The study of water-based fire-extinguishing agents used for LIBs is a promising direction. How to choose a suitable water-based fire-extinguishing agent is a significant scientific problem. In this study, a comprehensive evaluation model, including four primary indexes and eleven secondary indexes was established, which was used in the scenario of an electrochemical energy storage power station. The model is only suitable for assessing water-based fire extinguishing for suppressing lithium iron phosphate battery fire. Based on the comprehensive evaluation index system and extinguishing experiment data, the analytic hierarchy process (AHP) combined with fuzzy TOPSIS was used to evaluate the performances of the three kinds of water-based fire-extinguishing agents. According to the results of the fuzzy binary contrast method, the three kinds of fire-extinguishing agents could be ranked as follows: YS1000 > F-500 additive > pure water. The study provided a method for choosing and preparing a suitable fire-extinguishing agent for lithium iron phosphate batteries. Full article

The Energy Storage System (ESS) market is rapidly expanding as global environmental policies are pushing for renewable energy with an increasing momentum. However, due to the thermal runaway phenomenon specific to lithium-ion batteries (LIBs), ESSs are prone to catching fire, and initial suppression is difficult under current countermeasures. In this study, we introduce a liquid-immersed battery (LImB) ESS, in which the battery cells are fully submerged in a liquid agent. The full-immersion structure of the ESS with the particular thermal properties of the liquid agent blocks fire propagation. Moreover, the immersion system improves thermal management efficiency during normal operation. These enhanced thermal management performances of the LImB ESS were validated under various conditions at an independent energy station. These findings suggest that the liquid-immersed battery system paves the way for safe and efficient ESS operation by enhancing thermal management and fire suppression. Full article

With the safety and reliability of the electrical equipment used in information systems becoming more important, prefabricated fire-extinguishing devices using heptafluoropropane as the extinguishing agent have broad application prospects. However, few studies have focused on the vaporization performance of heptafluoropropane in the context of fire suppression and the safe distance for electrical equipment. This study proposes a numerical simulation model to analyze the vaporization and cooling performance of sprayed heptafluoropropane. First, experimental measurements with no fire source are performed to verify the numerical model. Through numerical and experimental methods, the temperature, concentration, and velocity distribution of the sprayed heptafluoropropane are analyzed to improve its vaporization performance and determine the safe distance. Finally, heptafluoropropane spraying with a fire source is simulated, allowing for the discussion of its cooling effect and fire-extinguishing performance. The results illustrate that the mass ratio of liquid and gas phases in the sprayed heptafluoropropane are 20.2% and 79.8%, respectively. Heptafluoropropane spraying reduced the average temperature in the protective room, with the final value reaching 270 K. The mass fraction of the heptafluoropropane maintained a value of 0.1 at a distance of 0.8 m in front of the nozzle axis. The main findings of this research indicate the temperature variation and fluid flow performance associated with heptafluoropropane spraying, as well as providing a reference value for a safe distance from the nozzle. Full article

Wildfire activity in the western U.S. has highlighted the importance of effective management to address this growing threat. The Lookout Mountain Thinning and Fuels Reduction Study (LMS) is an operational-scale, long-term study of the effects of forest restoration and fuel reduction treatments in ponderosa pine (Pinus ponderosa Dougl. ex Laws.) and mixed-conifer forests in central Oregon, U.S. The broad objectives of the LMS are to examine the effectiveness and longevity of treatments on wildfire risk and to assess the collateral effects. Treatments include four levels of overstory thinning followed by mastication of the understory vegetation and prescribed burning. Stands were thinned to residual densities of 50, 75, or 100% of the upper management zone (UMZ), which accounts for site differences as reflected by stand density relationships for specific plant communities. A fourth treatment combines the 75 UMZ with small gaps (~0.1 ha) to facilitate regeneration (75 UMZ + Gaps). A fifth treatment comprises an untreated control (UC). We examined the causes and levels of tree mortality that occurred 2–9 years after treatments. A total of 391,292 trees was inventoried, of which 2.3% (9084) died. Higher levels of tree mortality (all causes) occurred on the UC (7.1 ± 1.9%, mean ± SEM) than on the 50 UMZ (0.7 ± 0.1%). Mortality was attributed to several bark beetle species (Coleoptera: Curculionidae) (4002 trees), unknown factors (2682 trees), wind (1958 trees), suppression (327 trees), snow breakage (61 trees), prescribed fire (19 trees), western gall rust (15 trees), cankers (8 trees), mechanical damage (5 trees), dwarf mistletoe (4 trees), and woodborers (3 trees). Among bark beetles, tree mortality was attributed to western pine beetle (Dendroctonus brevicomis LeConte) (1631 trees), fir engraver (Scolytus ventralis LeConte) (1580 trees), mountain pine beetle (Dendroctonus ponderosae Hopkins) (526 trees), engraver beetles (Ips spp.) (169 trees), hemlock engraver (Scolytus tsugae (Swaine)) (77 trees), and Pityogenes spp. (19 trees). Higher levels of bark beetle-caused tree mortality occurred on the UC (2.9 ± 0.7%) than on the 50 UMZ (0.3 ± 0.1%) which, in general, was the relationship observed for individual bark beetle species. Higher levels of tree mortality were attributed to wind on the 100 UMZ (1.0 ± 0.2%) and UC (1.2 ± 1.5%) than on the 50 UMZ (0.2 ± 0.02%) and 75 UMZ (0.4 ± 0.1%). Higher levels of tree mortality were attributed to suppression on the UC (0.5 ± 0.3%) than on the 50 UMZ (0.003 ± 0.002%) and 75 UMZ + Gaps (0.0 ± 0.0%). Significant positive correlations were observed between measures of stand density and levels of tree mortality for most causal agents. Tree size (diameter at 1.37 m) frequently had a significant effect on tree mortality, but relationships varied by causal agent. The forest restoration and fuels reduction treatments implemented on the LMS increased resistance to multiple disturbances. The implications of these and other results to the management of fire-adapted forests are discussed. Full article

Clean agent fire suppression systems are commonly used to protect areas containing valuable or critical equipment, especially in data centers and electrical substations, where traditional fire suppression methods are less effective or pose additional risks. This review evaluates the IG-541 fire suppression system as an alternative to halocarbon-based agents like HFC-227ea and FK-5-1-12, which are being phased out under environmental regulations, focusing on their application in energized electrical fires. IG-541 offers environmental advantages, including zero ozone depletion potential, no global warming potential, and negligible atmospheric lifetime, making it compliant with stringent environmental regulations. This review compares IG-541 with halocarbon agents across parameters such as extinguishing efficacy, safety considerations, environmental impacts, cost impacts, and system design considerations. Key findings underscore IG-541’s effectiveness in reducing fire damage without producing harmful by-products or exacerbating climate change. Furthermore, the study highlights the regulatory frameworks influencing the phase-out of halocarbon agents and the transition toward environmentally sustainable alternatives. While IG-541 emerges as a promising replacement for halocarbon agents, further exploration into its application in varied fire scenarios and energy-intensive environments is recommended to optimize its deployment. Full article

Phosphate resources are non-renewable and are increasingly depleting. Currently, the primary raw material for commercial ABC dry powder fire-extinguishing agents is a processed product derived from the limited reserves of phosphorus ore. Consequently, there is an urgent imperative to innovate and develop novel types of dry powder fire-extinguishing agents. In this work, a simple physical blending process was utilized to modify the abundant and cost-effective hydromagnesite (HM) powder, which has been proven to be a promising dry powder extinguishant with a pronounced physical cooling effect on fire suppression. The HM powder added to 10 wt.% diammonium hydrogen phosphate (DAP) showed a shorter extinguishing time and a lower agent dosage compared with the unmodified powder and commercially available monoammonium phosphate (MAP) in both the liquid and solid fire experiments. Notably, the HM/DAP composite dry powder extinguished fires with the lowest CO concentration, indicating superior environmental friendliness and human safety. These findings indicate the potential of the HM/DAP composite dry powder as a promising candidate for future fire-extinguishing applications. Full article

Fires are classified into five types: A, B, C, D, and F/K, according to the components involved in combustion. Recognizing fire classes is critical, since each kind demands a unique suppression approach. Proper fire classification helps to decrease the risk to both life and property. The fuel type is used to determine the fire class, so that the appropriate extinguishing agent can be selected. This study takes advantage of recent advances in deep learning, employing YOLOv11 variants (YOLO11n, YOLO11s, YOLO11m, YOLO11l, and YOLO11x) to classify fires according to their class, assisting in the selection of the correct fire extinguishers for effective fire control. Moreover, a hybrid model that combines YOLO11n and MobileNetV2 is developed for multi-class classification. The dataset used in this study is a combination of five existing public datasets with additional manually annotated images, to create a new dataset covering the five fire classes, which was then validated by a firefighting specialist. The hybrid model exhibits good performance across all classes, achieving particularly high precision, recall, and F1 scores. Its superior performance is especially reflected in the macro average, where it surpasses both YOLO11n and YOLO11m, making it an effective model for datasets with imbalanced classes, such as fire classes. The YOLO11 variants achieved high performance across all classes. YOLO11s exhibited high precision and recall for Class A and Class F, achieving an F1 score of 0.98 for Class A. YOLO11m also performed well, demonstrating strong results in Class A and No Fire with an F1 score of 0.98%. YOLO11n achieved 97% accuracy and excelled in No Fire, while also delivering good recall for Class A. YOLO11l showed excellent recall in challenging classes like Class F, attaining an F1 score of 0.97. YOLO11x, although slightly lower in overall accuracy of 96%, still maintained strong performance in Class A and No Fire, with F1 scores of 0.97 and 0.98, respectively. A similar study employing MobileNetV2 is compared to the hybrid model, and the results show that the hybrid model achieves higher accuracy. Overall, the results demonstrate the high accuracy of the hybrid model, highlighting the potential of the hybrid models and YOLO11n, YOLO11m, YOLO11s, and YOLO11l models for better classification of fire classes. We also discussed the potential of deep learning models, along with their limitations and challenges, particularly with limited datasets in the context of the classification of fire classes. Full article

Lithium-ion batteries (LIBs) catch fire easily due to thermal runaway (TR). Fires following TR in LIBs pose a serious threat to public safety. Effective extinguishing methods for LIB fires have not been developed. In this work, the effect of a synergistic fire extinguishing method based on liquid nitrogen (LN) is evaluated for the suppression effect of LIB fires. LiNi_xCo_yMn_zO₂ (NCM) LIBs of 106 Ah were used in the experiments. The effects of LN, water and C₆F₁₂O (Perfluorohexanone) were compared separately, as well as the synergistic effects of LN with either water or C₆F₁₂O. The results show that all agents successfully extinguished the flame and prevented the battery from reignition. Spraying LN with water resulted in the highest efficiency, and achieved the lowest peak temperature rebound and rate of rebound. It also maintained low temperatures for twice as long as using LN alone. The results show that the synergistic extinguishing method based on LN offers significant advantages in fire control. This work provides a new perspective on suppressing LIB fires after thermal runaway. Full article

Although astaxanthin (AST) has demonstrated a modulatory effect on voltage-gated Ca²⁺ (Cav) channels and excitatory glutamate neuronal transmission in vitro, particularly on the excitability of nociceptive sensory neurons, its action in vivo remains to be determined. This research sought to determine if an acute intravenous administration of AST in rats reduces the excitability of wide-dynamic range (WDR) spinal trigeminal nucleus caudalis (SpVc) neurons in response to nociceptive and non-nociceptive mechanical stimulation in vivo. In anesthetized rats, extracellular single-unit recordings were carried out on SpVc neurons following mechanical stimulation of the orofacial area. The average firing rate of SpVc WDR neurons in response to both gentle and painful mechanical stimuli significantly and dose-dependently decreased after the application of AST (1–5 mM, i.v.), and maximum suppression of discharge frequency for both non-noxious and nociceptive mechanical stimuli occurred within 10 min. These suppressive effects persisted for about 20 min. These results suggest that acute intravenous AST administration suppresses the SpVc nociceptive transmission, possibly by inhibiting Cav channels and excitatory glutamate neuronal transmission, implicating AST as a potential therapeutic agent for the treatment of trigeminal nociceptive pain without side effects. Full article

Wildfires have short- and long-term impacts on the geoenvironment, including the changes to biogeochemical and mechanical properties of soils, landfill stability, surface- and groundwater, air pollution, and vegetation. Climate change has increased the extent and severity of wildfires across the world. Simultaneously, anthropogenic activities—through the expansion of urban areas into wildlands, abandonment of rural practices, and accidental or intentional fire-inception activities—are also responsible for a majority of fires. This paper provides an overall review and critical appraisal of existing knowledge about processes induced by wildfires and their impact on the geoenvironment. Burning of vegetation leads to loss of root reinforcement and changes in soil hydromechanical properties. Also, depending on the fire temperature, soil can be rendered hydrophobic or hydrophilic and compromise soil nutrition levels, hinder revegetation, and, in turn, increase post-fire erosion and the debris flow susceptibility of hillslopes. In addition to direct hazards, wildfires pollute air and soil with smoke and fire suppression agents releasing toxic, persistent, and relatively mobile contaminants into the geoenvironment. Nevertheless, the mitigation of wildfires’ geoenvironmental impacts does not fit within the scope of this paper. In the end, and in no exhaustive way, some of the areas requiring future research are highlighted. Full article

Polycarbonate/acrylonitrile butadiene styrene (PC/ABS) blends are widely used as engineering plastic alloys; however, they have a low fire safety level. To improve the flame-retardant property of PC/ABS, a zirconium-based metal-organic framework material (UiO-66) was synthesized with zirconium chloride and terephthalic acid and used as a flame-retardant cooperative agent. Its flame-retardant performance and mode of action in the PC/ABS blends were carefully investigated. The results showed that UiO-66 had good thermal stability and delayed the pyrolysis of the materials, thus significantly enhancing the efficiency of intumescent flame retardants. By compounding 7.0 wt% hexaphenyloxy-cyclotri-phosphazene (HPCTP) with 3.0 wt% UiO-66, the PC/ABS blends reached a limiting oxygen index value of 27.0% and V0 rating in the UL-94 test, showing significantly improved resistance to combustion dripping. In addition, UiO-66 enhanced the smoke and heat suppression characteristics of the intumescent flame-retardant materials. Finally, the flame-retardant mode of action in the blends was indicative of UiO-66 having a cooperative effect on the flame-retardant performance of PC/ABS/HPCTP materials. This work provides good ideas for further development of the flame-retardant ABS/PC. Full article