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In the article, a state analysis of the organic carbon-containing additives use in fire fighting has been carried out. Negative environmental effects when using fluorine-containing short- and long-chain surfactants, which can act as both a fire extinguishing agent and its decomposition product, have been noted. As an important direction for further evolution in the field of fire extinguishing agents, the use of oxysilanes and gel systems based on liquid glass as environmentally friendly compounds has been noted. The prospects and environmental friendliness of the use of acoustic effects in extinguishing fires have been noted. The addition of small amounts of inorganic and organic compounds is regarded as an inexpensive and effective method to increase the fire fighting properties of water. In this work, the ecological characteristics of a number of organic compounds used in fire fighting as thickeners of aqueous solutions and the reduction of their surface tension were studied. Alginic acid has been shown to be the most environmentally friendly water additive among the investigated organic carbon-containing compounds used in fire fighting. [ABSTRACT FROM AUTHOR]

Firefighter hoods must provide protection from elevated temperatures and products of combustion while simultaneously being comfortable and limiting interference with firefighting movement or completion of fireground activities. This study was to quantify the impact of hood design (traditional knit hood vs. several models of particulate-blocking hoods) on wearability measures such as range of motion, noise production and hearing threshold. Firefighters' perceptions of wearability were also collected. In a controlled laboratory environment, 24 firefighters performed movement and hearing tests. Wearing particulate-blocking hoods resulted in decreased rotational range of motion, and thicker hoods reduced hearing ability. Design, but not necessarily the number of layers, affected noise production by the hood during head movement. Practitioner summary: Particulate-blocking hoods resulted in reduced rotational range of motion relative to the traditional design and the no-hood condition. Hoods with additional layers resulted in decreased hearing ability. Noise production was increased in designs of particulate-blocking hoods with a membrane-based blocking layer independent of the number of layers. [ABSTRACT FROM AUTHOR]

Relevant studies in the fields of fire safety, occupational health and firefighter clothing were analyzed in this study to address the high injury rate among firefighters during fire rescue and the complexity of factors affecting skin burns. The findings indicate that the degree of skin burns in firefighters is primarily influenced by the heat source (heat flux, type), firefighter clothing (fabric, pattern) and the under-clothing air gap (thickness, characteristics). Since skin burns cannot be directly measured, internal skin heat transfer and burn prediction models are commonly employed to assess the impact of external factors on skin burns. These models can predict the safe working distance or time for firefighters. Investigating the influencing factors and prediction models of skin burns among firefighters holds significant value in enhancing operating procedures, optimizing firefighter clothing design and effectively preventing skin burns. [ABSTRACT FROM AUTHOR]

Ultrafine KAl(OH)2CO3 dry powder (UDWP), as a novel high-temperature-resistant ultrafine dry powder fire extinguishing agent, has garnered significant attention in the field of aviation fire protection. However, its development has been hindered by its hydrophilicity, which leads to hygroscopicity, and its tendency for re-ignition due to oil deposition. Therefore, this study employs perfluorodecyltrimethoxysilane (PFDTMS) to modify the surface of UDWP, resulting in hydrophobic and oleophobic M-UDWP. The thermal stability and hydrophobicity of M-UDWP ensure its long-term stable storage in aircraft equipment compartments, thereby reducing aircraft maintenance costs. Additionally, its oleophobicity provides excellent anti-re-ignition performance, protecting aircraft power compartments from secondary fire damage. Energy-dispersive X-ray spectroscopy (EDS), Fourier-transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS) analyses indicate that the PFDTMS modifier was successfully grafted onto KAl(OH)2CO3. Furthermore, M-UDWP exhibits a three-stage thermal decomposition process. The first-stage decomposition can be regarded as a single-step reaction, and the calculated kinetic parameters provide accurate predictions. Thermogravimetric analysis-Fourier transform infrared spectroscopy-mass spectrometry (TG-FTIR-MS) results reveal that M-UDWP significantly produces H2O and CO2 during thermal decomposition, which is one of its core fire extinguishing mechanisms. For the combustion of #RP-3 and #RP-5 aviation kerosene, commonly found in aircraft engine nacelles, the extinguishing times required by M-UDWP are 243 ms and 224 ms, respectively, with minimum extinguishing concentrations (MEC) of 25.9 g/m3 and 23.4 g/m3, respectively. The study of M-UDWP's thermal stability aids in understanding its storage stability under high-temperature conditions and its fire extinguishing mechanisms in fire zones. Moreover, the research findings suggest that M-UDWP has the potential to replace Halon 1301 in aircraft engine nacelles. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Electrochemistry is the property of Journal of Electrochemistry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Surface properties of three fluorocarbon surfactants with different carbon chain lengths were studied at low pressures of 94.6, 74.1 and 61.0 kPa, respectively. The results showed that the saturation adsorption capacity and the critical micelle concentration (CMC) decreased, while the average molecular area (AS) and the surface tension at CMC (γCMC) of fluorocarbon surfactants increased with decreasing pressure. The surface tension (γ) decreased with the decrease of pressure when the concentration of fluorocarbon surfactants was low. However, γ tended to be stable and increased with the drop of pressure when the concentration of surfactants was close or reach to CMC. In addition, the foaming and spreading performance of fluorocarbon surfactants decrease with the decrease of pressure, and the combination of fluorocarbon and hydrocarbon surfactants is beneficial to the improvement of performance (mixed systems: foam expansion E>6, 25% drainage time t25%>241 s, 1/2 defoaming time t1/2>851 s, spreading amount Vs>223 μL, spreading time ts<2 s). Further fire extinguishing experiment found that the influence of low pressure environment on fuel combustion characteristics is the key factor to determine fire extinguishing performance, while the influence of aqueous film‐forming foam (AFFF) performance is small. And AFFF based on the environmental‐friendly surfactant C4F9SO2NH(CH2)2N+(CH3)2CH2BrCH2OH (FC‐4) is an effective fire extinguishing agent under low pressure. [ABSTRACT FROM AUTHOR]

To study the influences of fire extinguishing agents on the mechanical performance of concretes after high temperatures, specimens of different curing ages were heated to different temperatures at 5 °C/ min and 10 °C / min heating rates, and then they were maintained at different constant temperatures of 200 °C, 400 °C, 600 °C and 800 °C for one hour. The mass loss rate of specimens of different curing ages and heating temperatures were tested. Specimens were moved into a tempered glass frame. Water, Halon 1211, CO2 and HFC-227ea were used to treat these specimens. The results showed that the mass loss rates of the specimen with 7 d and 14 d curing age were significantly higher than that in 28 d curing age at 400 °C . Fire extinguishing agents did not affect the compressive strength of the specimens at room temperature. Water, Halon 1211, and HFC-227ea could reduce compressive strength of the specimens after high temperature treatment at 400 °C and 600 °C . However, water cooling treatment at 600 °C could increase the compressive strength of the specimen with 7 d and 14 d curing age by 9.14% and 9. 18%. Curing age did not affect the experimental results of Halon 1211 and HFC-227ea, and the compressive strength of the specimen was relatively low at 800 °C, which could not reflect the influence of different treatment methods on the compressive strength. Water, Halon 1211, and HFC-227ea fire extinguishing agents could reduce the splitting tensile strength of concrete at 400 °C. CO2 had no influence on the compressive strength and splitting tensile strength of concrete. [ABSTRACT FROM AUTHOR]

Ammonium phosphate fire extinguishing agents, due to their excellent cost-effectiveness and suitability for forest fires, have become one of the most commonly used fire suppressants for forest fire control. Among them, NH 4 H 2 PO 4 fire extinguishing agent is the most widely applied. In this study, NH 4 H 2 PO 4 (>90%) as the main component of dry powder fire extinguishers was selected as the suppressant to investigate the reaction mechanism of NH 4 H 2 PO 4 interacting with red pine wood pyrolysis gas flames. Initially, we constructed a Bunsen burner experimental system suitable for NH 4 H 2 PO 4 /red pine wood pyrolysis gas/air. Although experimental methods yield the most intuitive empirical conclusions, measuring only the laminar flame speed of red pine wood pyrolysis gas/NH 4 H 2 PO 4 /air mixture does not adequately analyze the inhibitory mechanism of NH 4 H 2 PO 4 on red pine wood pyrolysis gas flames. Additionally, due to limitations in experimental equipment and methods, it is not feasible to extend equivalence ratios and NNH 4 H 2 PO 4 doses to large or small working conditions. Therefore, in this study, we utilized Chemkin software to construct theoretical models of flames under different conditions and performed calculations. We comprehensively analyzed the kinetic regulatory mechanisms of NH 4 H 2 PO 4 interacting with red pine wood pyrolysis gas flames from aspects such as chemical inhibition, sensitivity of elementary reactions, elementary reaction yields, and chemical reaction pathways. • The laminar flame velocity of NH 4 H 2 PO 4 interacting with the pyrolysis gas flame of red pine was measured. • A comprehensive analysis of the dynamic regulation mechanism of NH4H2PO4 interaction with pyrolysis gas flame of red pine. • The inhibition mechanism of phosphorus-containing active substances on pyrolysis gas flame of red pine wood was elucidated. • Provide theoretical and experimental reference for development of more efficient fire extinguishing agents for forest fires. [ABSTRACT FROM AUTHOR]

Flowability greatly affects the application of ultrafine dry powder fire extinguishing systems, while hydrophobicity and acute inhalation toxicity are concerns for fire extinguishing agents. In the present study, we examined the impact of hydrophobic fumed silica on the hydrophobicity and flow properties of ammonium dihydrogen phosphate as the base. Our findings revealed that incorporating 6 wt.% of hydrophobic fumed silica resulted in optimal flowability, accompanied by a hydrophobicity angle of 126.48°. The excessive inclusion of hydrophobic fumed silica impeded powder flow within the ammonium dihydrogen phosphate particles. Furthermore, the investigations indicated that the incorporation of a small quantity of bentonite (0.5 wt.%) amongst the three functional additives—bentonite, magnesium stearate, and perlite—offered further enhancements in powder flowability. In fire extinguishing experiments' total flooding conditions (1 m3), the designed UDPA exhibited a minimum required extinguishing concentration of merely 41.5 g/m3, which is better than the publicly reported value. Moreover, observations on the well-being of mice subjected to nearly three times the extinguishing concentration at 60 s, 10 min, and 3 days, respectively, demonstrated the absence of acute inhalation toxicity associated with the designed UDPA. Collectively, the developed ultrafine dry powder fire extinguishing agent displayed promising performance and possesses broad applicability. [ABSTRACT FROM AUTHOR]

The research and development of alternatives to long-chain fluorocarbon surfactants are desperately needed because they are extremely toxic, difficult to break down, seriously harm the environment, and limit the use of conventional aqueous film-forming foam fire extinguishing agents. In this study, mixed surfactant systems containing the short-chain fluorocarbon surfactant perfluorohexanoic acid (PFHXA) and the hydrocarbon surfactant sodium dodecyl sulfate (SDS) were investigated by molecular dynamics simulation to investigate the microscopic properties at the air/water interface at different molar ratios. Some representative parameters, such as surface tension, degree of order, density distribution, radial distribution function, number of hydrogen bonds, and solvent-accessible surface area, were calculated. Molecular dynamics simulations show that compared with a single type of surfactant, mixtures of surfactants provide superior performance in improving the interfacial properties of the gas–liquid interface. A dense monolayer film is formed by the strong synergistic impact of the two surfactants. Compared to the pure SDS system, the addition of PFHXA caused SDS to be more vertically oriented at the air/water interface with a reduced tilt angle, and a more ordered structure of the mixed surfactants was observed. Hydrogen bonding between SDS headgroups and water molecules is enhanced with the increasing PFHXA. The surface activity is arranged in the following order: PFHXA/SDS = 1:1 > PFHXA/SDS = 3:1 > PFHXA/SDS = 1:3. These results indicate that a degree of synergistic relationship exists between PFHXA and SDS at the air/water interface. [ABSTRACT FROM AUTHOR]

The task related to using inorganic compounds for extinguishing flames is to enable their inhibitory capacity during operation within wide limits. Therefore, the object of the current research was aqueous solutions of inorganic salts, on which the effectiveness of inhibitory properties during interaction with n-heptane flame was established. It has been proven that increasing the mass flow rate of water by 1.5 mg/s reduces the intensity of OH-radicals radiation from 70 % to 30 % and lowers the flame temperature by 90 °C. However, it was found that when potassium salts are given, the intensity of OH-radicals radiation decreases by more than 6 times, potassium chloride and sulfate reduce the intensity of OH-radicals radiation by more than 2.8 times. Among ammonium salts, salts of dihydrogen phosphate and ammonium hydrogen phosphate reduce the relative intensity of radiation of OH radicals by more than 1.3 times. Sodium salts include nitrates and sodium chloride, which reduce the relative radiation intensity of OH radicals by more than 1.6 times. This is manifested, first of all, in the enrichment of the combustible environment with fuel. When determining the flame temperature of flammable liquids, it was established that n-heptane has the most stable and highest flame temperature, which is 1768 °C. When adding inorganic compounds to the flame of n-heptane, nitrate salt, and potassium chloride, the flame temperature increased by less than 20 °C. However, ammonium salts increased the flame temperature to over 140 °C, despite the presence of water. The practical significance is that the results were taken into account during the design and development of extinguishing agents for extinguishing fires. Therefore, there are reasons to assert the possibility of regulating flame extinguishing processes by using inorganic compounds capable of inhibiting active flame radicals. [ABSTRACT FROM AUTHOR]

As the use of Li-ion batteries is spreading, incidents in large energy storage systems (stationary storage containers, etc.) or in large-scale cell and battery storages (warehouses, recyclers, etc.), often leading to fire, are occurring on a regular basis. Water remains one of the most efficient fire extinguishing agents for tackling such battery incidents, and large quantities are usually necessary. Since batteries contain various potentially harmful components (metals and their oxides or salts, solvents, etc.) and thermal-runaway-induced battery incidents are accompanied by complex and potentially multistage fume emissions (containing both gas and particles), the potential impact of fire run-off waters on the environment should be considered and assessed carefully. The tests presented in this paper focus on analyzing the composition of run-off waters used to spray NMC Li-ion modules under thermal runaway. It highlights that waters used for firefighting are susceptible to containing many metals, including Ni, Mn, Co, Li and Al, mixed with other carbonaceous species (soot, tarballs) and sometimes undecomposed solvents used in the electrolyte. Extrapolation of pollutant concentrations compared with PNEC values showed that, for large-scale incidents, run-off water could be potentially hazardous to the environment. [ABSTRACT FROM AUTHOR]

A new non-toxic, clean, and effective dry water (DW) nanomaterial is synthesized, and its extinguishing performance is characterized for pool fire. The nanomaterial reaches up to 93% water content due to its special core–shell structure. Phytic acid (PA) is used to functionalize DW to obtain DW/PA because of its biocompatibility and phosphorus-rich properties. The results of the Fourier transform infrared, X-ray photoelectron spectroscopy, thermal gravity analyzer, and optical microscope successfully verify the preparation of DW/PA samples. The DW/PA samples are cylindrical particles with a length of 100–200 μm and have excellent fluidity, with a repose angle of about 29°. The centrifugation and water loss rate tests indicate that the samples have appropriate mechanical stability and are suitable for storage in closed spaces. The extinguishing efficiency of DW/PA samples is characterized using a fire-extinguishing experiment designed by international standards. The average extinguishing time and consumption of DW/PA samples are reduced by 77.08% and 77.67%, respectively, comparing with commercial ABC dry powder-extinguishing agents. Moreover, fire-extinguishing efficiency is positively correlated with PA content. According to experimental results and established theories, the extinguishing mechanism of DW/PA samples is discussed and divided into three parts: chemical inhibition, the cooling effect, and the asphyxiation effect. [ABSTRACT FROM AUTHOR]

Four types of modified dry water samples(DW)with different components were developed and ready for use in oil leakage incidents. The fire extinguishing experiment platform was constructed to investigate the fire extinguishing effectiveness of several DW groups on oil fires. The characterization and analysis were performed using an optical microscope, a laser particle size analyzer, and a thermogravimetric analyzer. The findings demonstrate that the prepared DW has a robust core-shell structure and its interior water content can range from 80% to 90%. The volume density of the fire extinguishing agents and gels can be increased, which helps the agent reach the flame root more effectively and boost the efficacy of fire extinguishing. In the fire extinguishing test, the pure water DW1 fire is extinguished in 49 s, whereas the fire is extinguished in 17 s when DW4 is added with potassium oxalate and gel agent. This represents a 65.3% reduction in fire extinguishing time, fully utilizing the role of physical and chemical inhibition and significantly cutting down on fire extinguishing time. The findings have significant implications for the petrochemical industry's use of dry water extinguishing agents. [ABSTRACT FROM AUTHOR]

Image recognition methods for the partial inspection of fire safety equipment – a study considering machine learning techniques and the integration of expert knowledge This paper explores the potential application of artificial intelligence (AI) and computer vision in the context of Building Information Modeling (BIM) for documenting fire safety equipment. Detection algorithms, particularly current You Only Look Once (YOLO) models, are utilized to automatically identify fire safety equipment such as fire extinguishers, fire blankets, smoke detectors, and fire alarms in images. The results demonstrate high detection accuracy in both images. Future work aims to expand automated detection by directly integrating it into BIM models. In addition, the importance of expert knowledge in determining the extinguishing agent type of a fire extinguisher is addressed to verify and, if necessary, correct the prediction of an AI‐based fire safety inspection. The developed AI applications aim to increase the level of automation in fire safety inspections to improve the safety of buildings in the operational phase. [ABSTRACT FROM AUTHOR]

Fit of fire boots is a crucial factor in the safety and performance of firefighters on the hostile fireground. Firefighters have reported that ill-fitting fire boots restrict their lower body movement and sometimes cause very dangerous situations by falling off behind the wearer. By using computed tomography, this study demonstrates the potential to quantify and visualize the fit of fire boots, which previously relied on subjective feedback from the wearers. The high-resolution three-dimensional (3D) models of two fire boot products allowed a detailed observation and measurement of the internal space of the boots. Also, the boot's internal dimension was compared to the foot measurement of local firefighters, showing the significant differences between the two boots. Lastly, simulation wrapping the 3D scanned foot with the boot revealed large void spaces around the toe box and ankle, as well as the narrower ball width of the boot than the foot. [ABSTRACT FROM AUTHOR]

Objective: The aim of the study is to determine the physiological effects of breathing apparatus and ascent strategies during a simulated 120-m vertical high-rise firefighting ascent. Methods: Twenty-eight firefighters completed four high-rise firefighting trials wearing standard- or extended-duration breathing apparatus with continuous ascent (SDBA-C/EDBA-C) or with breaks (SDBA-B/EDBA-B). Task time, heart rate, ratings of perceived exertion, core body temperature, and thermal comfort were recorded at predetermined elevations. Results: Task time took significantly longer during the EDBA-C compared with SDBA-C trial. Heart rate (at 40, 80, and 100 m) was significantly lower in trials following breaks compared with the continuous trials. Core body temperature rose by 0.11°C every 10 m of ascent. During the SDBA trials, 89% to 96% of firefighters activated their low air alarm compared with only 7% in EDBA. Conclusions Firefighters should wear EDBA beyond 80 m of ascent and are encouraged to take regular breaks. [ABSTRACT FROM AUTHOR]

The water mist (WM) is currently an important environmentally friendly fire extinguishing agent, offering a distinct advantage in efficiently cooling and inhibiting the thermal runaway (TR) behavior of lithium battery (LIB). Numerous studies have explored the additives of WM to extinguish LIB fires more efficiently. However, the inhibition mechanism of WM containing additives on TR of LIB has not been revealed clearly, and the principle of adding additives remains to be further studied. In this study, three types of non-ionic surfactants are examined and their effects on the maximum temperature during TR and the cooling time of WM are compared. The results indicate that foam induced by the additives has certain advantages in mitigating LIB TR. Further the defoamer is used to modify the foaming performance of the additive solution, and it is found that an appropriate increase in the brittleness of the foam can greatly decrease the highest temperature of the battery during TR moment. These findings can serve as a valuable reference for future applications of WM with additives in the design of battery fire suppression systems. [ABSTRACT FROM AUTHOR]

So far too long, people have been working hard to develop fire prevention measures to deal with lithium ion battery (LIB) fires. LIB fires have a high calorific value, a rapid burning and spread speed and a high risk of re-ignition and explosion. Under thermal runaway, LIB fires develop from the inside out, preventing fire extinguishing agents from entering the interior of LIB, thus resulting in low extinguishing efficiency or even failure of the extinguishing agents. Based on the principle of 'isolation and stifling', fire-blocking blanket can effectively inhibit the spread of fire, suppress the combustion intensity and reduce the smoke emission. This paper digs into the detailed performance requirements of fire blanket to block LIB fires. By conducting laboratory tests to mimic LIB fires, the candidate materials including fiber materials, woven textile and woven fabrics with organic coatings are systematically investigated. Performance of the materials are evaluated, including fire resistance, thermal insulation, tensile strength at break and blast resistance, respectively. The testing results help to screen out the best material for LIB fire blanket, and high-silica glass fiber coated by polyurethane has the best thermal and mechanical properties among all materials tested. This paper also presents a three-layer structured design of blanket, which can pass all the tests proposed. [ABSTRACT FROM AUTHOR]

Copyright of Safety & Fire Technology (2657-8808) is the property of Centrum Naukowo-Badawcze Ochrony Przeciwpozarowej and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A portable lab scale test setup (1 × 1 × 0.72 m3) with apparatus and procedure has been illustrated to test the fire extinguishability of fire retardant materials (FRMs) as water additives on class A fires. The main objective was to use selected commercial, eco‐friendly FRM powders such as hydroxides, carbonates, and clays as water additive‐based fire extinguishing agents for suppressing solid fires. FRM powders, namely, Mg(OH)2, Ca(OH)2, CaCO3, and MMT‐Clay were added to water and were mist sprayed on a wooden fire (class A) to test their fire‐suppressing ability. A comparison involving tests with only water (without any additives) was also recorded. The solutions made with FRM additives in water showed promising results in suppressing the fire in comparison to systems with only water as an extinguishing agent. Heat sink materials, such as hydroxides and clays depicted commendable performances in retarding the burning process and almost doubled the capability of fire suppression with low loading. Their heat‐absorbing nature resisted the increase in temperature and slowed down the burning process causing an increase in the total burning time of the crib and avoiding reignition. Whereas, carbonates (CaCO3) showed a faster flame out by the release of CO2 gas, which diluted the oxygen content in the surroundings. The article concludes with a discussion of the requirements for the ideal water mist additive‐based fire extinguishing agent and a recommendation that future work include validation of the laboratory‐scale method based on a comparison with full‐scale suppression data for the same additives. [ABSTRACT FROM AUTHOR]

The rheological characteristics of struvite-based fire extinguishing powder mixtures are comparatively analyzed when using hydrophobic silicon dioxide as a functional filler, obtained during a single-stage synthesis by various methods. Infrared spectroscopy, scanning electron microscopy, low-temperature nitrogen sorption–desorption, and other methods are used to investigate the influence of the synthesis method on the textural and structural properties of hydrophobic functional fillers of fire extinguishing powder mixtures. It is revealed that the key factor affecting the rheological properties of such mixtures is the uniform distribution of the functional filler over the surface of the particles of a fire extinguishing component (struvite). It is proven that the struvite-based powder composition and the developed functional filler are highly effective for fire extinguishment. [ABSTRACT FROM AUTHOR]

Efficient fire extinguishing is a safety prerequisite for protecting the environment from fire damage. Understanding the effect of fire extinguishing agent on flame in complex environment is basic work for efficient fire extinguishing. We investigate the impact of HFC-125 on the extinguishment of propane-air highly stretched diffusion flames. Flame thickness is measured using the proportional method. Parameters such as dimensionless flame stand-off distance and flame stretch rate are calculated. Low concentrations of HFC-125 initially increase the flame thickness, but as the concentration increases further, the flame thickness decreases and the flame suppression effect of HFC-125 intensifies. HFC-125 reduces the amount of carbon soot generated and accelerates the transition from yellow to blue flame. Within a specific concentration range, N 2 has a minimal effect on flame structural parameters compared to HFC-125. High concentration of N 2 forms a high bright blue flame, while HFC-125 reacts with the flame to form a blue-violet flame. Compared to HFC-125, HFC-227ea can significantly reduce flame thickness and increase dimensionless flame stand-off distance, exhibiting a notable suppression effect. Furthermore, high concentrations of HFC-125 substantially reduce the critical flame stretch rate and provide a lower extinguishing concentration in counterflow diffusion flames than in the cup burner. [ABSTRACT FROM AUTHOR]

The object of this study is a class B fire, which is extinguished with sprayed water. The subject of the study is the characteristics of class B fires when they are extinguished with sprayed water. Diffusion burning of a flammable liquid is considered as such a fire, and its extinguishing is carried out by cooling the flame. Heat and oxygen balance equations are used to build a mathematical model describing the fire extinguishing process. The components of the heat balance equation are the power of heat during heat release due to the chemical reaction of liquid combustion and the power of heat dissipated to the environment. The second component takes into account heat removal due to radiation, convection, and evaporation. The component of removed heat due to evaporation takes into account the Sreznevsky constant. The mathematical model that describes the process of extinguishing a class B fire is built in the class of models belonging to differential equations with constant coefficients. Analytical expressions were obtained for these static and dynamic coefficients, which include thermophysical, kinematic, and geometric parameters of the flame and fire extinguishing agent. To determine these characteristics, the constructed mathematical fire model was transformed using the integral Laplace transform. The dynamic characteristics of the fire were obtained in the time domain – the transient function of the fire, and in the frequency domain – the amplitude-frequency and phase-frequency characteristics of the fire. It is shown that the parameters of these dynamic characteristics should be determined experimentally. Experimental methods for determining parameters of dynamic fire characteristics have been devised. The presence of dynamic characteristics of class B fire makes it possible to spread the proven methods of the theory of control systems to design effective fire extinguishing systems [ABSTRACT FROM AUTHOR]

Objectives. Postural imbalance can result from hyperthermia-mediated muscular fatigue and is a major factor contributing to injuries from falling. The objective of this study was to investigate the effect of exercise-induced hyperthermia and the impact of cooling on postural balance while wearing fire-fighters' protective clothing (FPC) in a hot environment. Methods. A portable force platform measured postural balance characterized by postural sway patterns using center of pressure metrics. Twelve healthy, physically fit males were recruited to stand on the force platform once with eyes open and once with eyes closed before and after treadmill exercise (40% ...O2max) inside an environmental chamber under hot and humid conditions (30 °C and 70% relative humidity) while wearing FPC. Subjects participated in two randomly assigned experimental phases: control and cooling intervention. Results. A significant increase in physiological responses and postural balance metrics was observed after exercising in the heat chamber while wearing FPC. Cooling resulted in a significant effect only on postural sway speed after exercise-induced hyperthermia. Conclusions. Hyperthermia can negatively alter postural balance metrics, which may lead to an increased likelihood of falling. The utilization of body cooling reduced the thermal strain but had limited impact on postural balance stability. [ABSTRACT FROM AUTHOR]

With the implementation of the green energy development strategy, new energy vehicles and related industries have been experiencing rapid growth, leading to an expansion in the market scale of the lithium-ion battery (LIB) industry. While the high energy density of LIB is being pursued, the risk of thermal runaway (TR) cannot be underestimated. Water mist (WM) is currently considered an efficient and environmentally friendly fire extinguishing agent, highly favored for its exceptional cooling capabilities. In this study, an alternative WM control strategy is proposed that capitalizes on the distinct advantages of varying particle sizes of WM during different cooling stages and integrates them to enhance overall cooling effectiveness. The experimental results demonstrate that the utilization of WM with mixed particle sizes not only reduces the peak temperature of TR, but also significantly shortens the cooling time. Compared to using WM with a single particle size, this method greatly reduces water consumption and enhances its utilization rate. This finding can offer valuable suggestions for the future implementation of WM in battery fire suppression systems design. [ABSTRACT FROM AUTHOR]

Sodium bicarbonate and potassium bicarbonate are commonly used as the bases of dry powder fire extinguishing agents. However, the choices of particle diameter and base are still not obvious, bringing difficulties to the design of fire extinguishing agents. Through the study on thermal decomposition kinetics, it was found that the smaller the particle size, the faster the decomposition rate of dry powder agents. For instance, if the D90 of sodium bicarbonate is reduced from 46.2 to 1 μm, the decomposition rate triples. As determined by thermal decomposition experiments, the residues after a fire could be bicarbonates, carbonates, and mixtures. The residue solutions' pH shows that carbonates are more alkaline than bicarbonates, and potassium salts are more alkaline than sodium salts. The corrosion tests on four common metals reveal that the residues of potassium bicarbonate after a fire could accelerate the electrochemical corrosion of metal surfaces, especially aluminum alloys. This research identifies the ideal particle diameter and supports the choice of alkali metal salts for the design of dry powder agents. [ABSTRACT FROM AUTHOR]

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Thermosensitive hydrogels have been receiving attention in the development of fire extinguishing agents due to their stimuli responsivity. Conventional hydrogels are limited by their slow response rate, and their wettability has not been studied systematically. In the present study, a concentrate of a thermosensitive porous system has been successfully synthesized by adding Na2CO3/CH3COOH as a foaming agent into the mixture of hydroxypropyl methylcellulose (HPMC)/polyethylene glycol (PEG)/chitosan (CS). The systems with different concentrations were obtained by diluting the concentrate with water. Thermosensitivity, surface tension and contact angle were characterized. In addition, spreadability, wettability and adhesivity were investigated systematically. Results showed that the systems with a concentration greater than 15 wt% exhibited outstanding performance of thermosensitivity and coagulability. A total of 20 wt% of the system has the best spreadability and wettability on the wood surface, most likely due to favorable contributions brought by both adequate viscosity and hydrophilicity. The adhesive force and surface-free energy of the pre-gel droplet that reached deposition on the wood surface decreased by 46.78% and 20.71%, respectively. The gel has a great capacity of water retention over a long period of time, which makes this porous gel the best system when it comes to its wettability and adhesiveness towards the chosen wood surface. The equilibrium surface tension decreased by 45.50% compared with water. HPMC/PEG/CS thermosensitive porous hydrogel with excellent wettability presented wide-ranging possibilities for the further development of fire suppression agents of fast phase-transition thermosensitive hydrogel. [ABSTRACT FROM AUTHOR]

Efficient and environmentally friendly means for fire extinguishing can reduce extreme economic losses from fires and protect people's lives and property. A separate problem is extinguishing oil products on the water surface. Dry water is a new type of environmentally friendly fire extinguishing agent. It is a powder with a water content of more than 90 %, so it has excellent fire extinguishing properties. The purpose of this work was to obtain dry water fire extinguishing powders based on pyrogenic hydrophobic methyl silica with bentonite and to study their fire extinguishing properties in case of extinguishing gasoline on water surface. To obtain dry water fire extinguishing powders, there were used distilled water, Dashukovsky bentonite (Ukraine), and pyrogenic methyl silica (AM-300 brand, Ssp = 300 m² /g, particle size 5–7 nm) (Kalush, Ukraine). Dry water fire extinguishing powder was prepared by mixing the components at a speed of 15000 rpm for 10 s. Were made samples containing 10 wt. % methyl silica, 3, 6, 10, and 15 wt. % bentonite and the corresponding amount of water. The bulk density was 0.423, 0.453, 0.459, and 0.464 g/cm³ for samples of 3, 6, 10, and 15 wt. % bentonite, respectively. Optical microscopy has shown that the particles of the dry water powder have a clearly visible core-shell structure. Dry water fire extinguishing powder is a polydisperse system - most of the particles are single fine particles with a size of 1 micron or less, and there are also agglomerates with a size of more than 5 microns. As a result of the mechanical destruction of individual bentonite particles during high-speed mixing of components, bentonite particles are destroyed, therefore, individual bentonite particles are surrounded by a hydrophobichydrophilic mixture of hydrophobic silica nanoparticles and bentonite nanoparticles formed during exfoliation. The study of the fire-extinguishing properties of the dry water powder was carried out by spraying it onto a layer of burning gasoline A92 on water surface. The time to complete extinguishing of the fire and the consumption of the substance per unit area of burning were determined. It has been determined that the time for extinguishing gasoline and the consumption of dry water fire extinguishing powder for extinguishing it depend on the concentration of bentonite and are for 3, 6, 10, and 15 wt. % 9, 7, 6, and 9 s and 0.333, 0.309, 0.284, and 0.260 g/cm³, respectively. The developed dry water fire extinguishing powders are environmentally friendly, have good fire extinguishing properties, and can be used to extinguish oil products on the surface of water bodies. [ABSTRACT FROM AUTHOR]

As the industrial revolution progresses, carbon dioxide (CO2) and sulfur dioxide (SO2) are major concerns because they are the main contributors to greenhouse gases. The concentration of these harmful gases in the industry is very high, which is emitted by workers and industrial materials. Therefore, it is required to maintain a safe percentage of CO2, SO2, and other harmful gases in the air of industry and ensure safety from fire accidents. This paper presents a compressor driven system that could capture harmful gases including CO2 and SO2 from the polluted air of different industries and households. The captured and separated CO2 works as a fire extinguishing agent to safeguard fire accidents for large industries and households. Thus, this system ensures a protected working place and a healthy atmosphere for industrial workers. Besides, this system can be applied in place of the exhaust gas recirculation (EGR) system in small industries and for a four-wheeler, internal combustion engine, as this system could capture and separate the harmful carbon dioxide and sulfur dioxide. This paper also presents a developed model of different polymeric membranes to simulate the separation of carbon dioxide after the post-combustion process. Computational Fluid Dynamics (CFD) has been performed by COMSOL 5.5 to observe the carbon dioxide separation by polymeric membranes like polycarbonate (0.07 mol/m3) and polytetrafluoroethylene (0.1 mol/m3) polymeric membranes for specific pore sizes which is comparable to experimental data (0.05 mol/m3). [ABSTRACT FROM AUTHOR]

An issue related to the use of foaming agents to extinguish fires involving flammable liquids is to ensure the efficiency of vapor insulation of flammable liquid and the foam stability during operation. Therefore, the object of research was a change in the insulating properties of the foaming agent film when interacting with a polar combustible substance. It has been proven that the presence of foaming agent on a flammable liquid leads to the formation of an insulating film on the surface resistant to the combustion temperature of the liquid, due to which re-ignition shifts towards longer time. A film of foaming agent was formed on the surface of the flammable liquid by leaking from the screen, which led to the insulation of the surface. The measured contact area of the foaming film with the electrode was more than 6.2·10-3 m2, which indicates the formation of a barrier for temperature, which collapses over time. According to experimental data on changes in electrical resistance, the critical contact area of the foaming film with the electrode was calculated, at which the film is destroyed. Based on the derived dependences, the change in the process of mass transfer of the foaming film to a flammable liquid was calculated, equal to about 800 s. The maximum possible mass transfer of the foaming agent into the flammable liquid and the reduction of insulation capacity were evaluated. The peculiarities of foam supply to the surface of alcohol through the screen are that the quenching time was about 156 s while the critical intensity of the supply of the working solution of the foaming agent was 0.054 dm3/(m2·s). And the time interval before re-ignition was about 470 s, which is enough to cool the fire site. Thus, there is reason to assert the possibility of targeted control over the processes of extinguishing polar flammable liquids with a foaming agent. [ABSTRACT FROM AUTHOR]

As an excellent fire extinguishing agent, FK-5-1-12 has been widely used in industry. This article studies the fire extinguishing performance of FK-5-1-12 on a full-size battery box experimentally, triggered into thermal runaway by heating a lithium iron phosphate battery. By analyzing the extinguishment, reignition, as well as temperature changes on the battery surface and in the vicinity of the safety valve, the efficacy of the extinguishing agent under real circumstances of a lithium iron phosphate battery fire was investigated, using different loading of FK-5-1-12. The performance of FK-5-1-12 is analyzed and evaluated in combination with the flame extinguishing effect and the cooling effect. [ABSTRACT FROM AUTHOR]

It is necessary to develop novel and efficient alternatives to fluorocarbon surfactant and prepare fluorine-free environmentally-friendly fire extinguishing agent. The carboxyl modified polyether polysiloxane surfactant (CMPS) with high surface activity was synthesized via the esterification reaction using hydroxyl-containing polyether modified polysiloxane (HPMS) and maleic anhydride (MA) as raw materials. The process conditions of the esterification reaction were optimized by orthogonal tests, and the optimum process parameters were determined as follows: reaction temperature of 85 °C, reaction time of 4.5 h, isopropyl alcohol content of 20% and the molar ratio of HPMS/MA of 1/1. The chemical structure, surface activity, aggregation behavior, foam properties, wetting properties and electron distribution were systematically investigated. It was found that the carboxyl group was successfully grafted into silicone molecule, and the conjugated system was formed, which changed the interaction force between the molecules and would affect the surface activity of the aqueous solution. The CMPS exhibited excellent surface activity and could effectively reduce the water's surface tension to 18.46 mN/m. The CMPS formed spherical aggregates in aqueous solution, and the contact angle value of CMPS is 15.56°, illustrating that CMPS had excellent hydrophilicity and wetting performance. The CMPS can enhance the foam property and has good stability. The electron distribution results indicate that the introduced carboxyl groups are more inclined towards the negative charge band, which would be conducive to weak the interaction between molecules and improve the surface activity of the solution. Consequently, new foam fire extinguishing agents were prepared by using CMPS as a key component and they exhibited excellent fire-fighting performance. The prepared CMPS would be the optimal alternative to fluorocarbon surfactant and could be applied in foam extinguishing agents. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries (LIBs) are widely used in electrochemical energy storage and in other fields. However, LIBs are prone to thermal runaway (TR) under abusive conditions, which may lead to fires and even explosion accidents. Given the severity of TR hazards for LIBs, early warning and fire extinguishing technologies for battery TR are comprehensively reviewed in this paper. First, the TR reaction mechanism and hazards of LIBs are discussed. Second, the TR early warning and monitoring methods of LIBs are summarized in five aspects consisting of acoustic, heat, force, electricity, and gas. In addition, to reduce the fire and explosion hazards caused by the TR of LIBs, the highly efficient extinguishing agents for LIBs are summarized. Finally, the early warning technology and fire extinguishing agent are proposed, which provides a reference for the hazard prevention and control of energy storage systems. [ABSTRACT FROM AUTHOR]

A strain of bacteria M1, defluorinating perfluorooctanesulfonic acid (PFOS), was isolated from soil taken from the territory for testing fire extinguishing agents. The analysis of cultural, morphological, physiological and biochemical characters, the 16S rRNA gene sequencing allowed us to identify strain M1 as Ensifer adhaerens. The uniquely skill of the isolated strain to utilize PFOS in a mineral liquid medium for 5 days of cultivation was shown. It was found that E. adhaerens M1 transforms perfluorooctanesulfonic acid into perfluoroheptanoic acid, releasing 152 mg/L of free fluoride ions from 1,000 mg/L of PFOS. The data obtained allow us to recommend E. adhaerens M1 as potential treatment agent of the environment from organofluorine compounds. [ABSTRACT FROM AUTHOR]

BACKGROUND: Chemical accidents have imposed casualties and high economic and social consequences to Iranian industries and society. OBJECTIVE: This study investigated the effect of risk factors involved in occurrences of the chemical accidents and predicted the time of occurrences in Iranian chemical factories. METHODS: A cross-sectional study was implemented in 574 chemical facilities with more than 25 employees from 2018 to 2020. Collecting data instruments were 2 checklists with 15 and 25 three-point Likert scale questions, respectively. Chi square and Monte Carlo tests assessed the relationships between independent risk factors and dependent hazardous chemical accidents. Cox semi-parametric and log-normal parametric models were used to predict the upcoming time of chemical accidents based on the impacts of risk factors understudy. Data analyses were performed using Stata and R software. RESULTS: The results showed that safety data sheets, labeling, fire extinguishing system, safe chemicals storage, separation, loading, transportation and training were statistically significant with occurrences of the chemical accidents (P-value < 0.05). Loading and transportation were mostly related to chemical incidents and reduced significantly the expected time of chemical events (P-value = 0.028). CONCLUSION: Establishing a comprehensive chemical accidents dataset and strict governmental supervision on chemical safety regulations are suggested to decrease the chemical accidents at regional and local levels in chemical plants. [ABSTRACT FROM AUTHOR]

Woodland fires are a major issue worldwide. The aviation method of extinguishing forest fires is one of the main ones. However, the use of the latter is carried out according to the results of experiments, bench or flight tests in the absence of models that adequately describe the mechanisms for suppressing the combustion of forest combustible materials with specific fire extinguishing compositions (solutions, emulsions or suspensions). Therefore, the task of studying the evaporation and interaction of single drops with the surfaces of combustible materials is relevant and practically significant in the field of fire hazards. The paper presents the experimental research findings on the evaporation of specialized composition droplets for extinguishing fires under different heat supply schemes. The compositions under study included a group of widely used fire extinguishing agents: water; flame retardant FR-Les (5% solution); FR-Les (20% solution); bentonite slurry (1%); bentonite slurry (5%); bischofite solution (5%); bischofite solution (10%); fire extinguishing agent OS-5 (5% solution); fire extinguishing agent OS-5 (10% solution); fire extinguishing agent OS-5 (15% solution); foaming agent emulsion (1%); foaming agent emulsion (5%); fire retardant (5% solution). Specialized composition droplets were heated using conductive, convective and radiant heating. Empirical coefficients were obtained. [ABSTRACT FROM AUTHOR]

Coal fires, most of which are triggered by the spontaneous combustion of coal, cause a huge waste of resources and release poisonous and harmful substances into the environment, seriously threatening the safety of industrial production. Gel flame retardant plays a core role in coal fire prevention and extinguishing. Most gel flame retardants used in coal fires possess good sealing and oxygen isolation properties, but it is difficult for them to flow deep into fire areas due to their low fluidity. Some fire extinguishing agents with good fluidity lack leak-blocking performance. In order to simultaneously improve the fluidity, leakage sealing, and oxygen isolation effects of coal fire extinguishing colloids, a novel, pH-sensitive, sol-gel transition colloid was prepared using low methoxyl pectin (LMP), calcium bentonite (Ca-Bt), sodium bentonite (Na-Bt), and water as the main components. When the initial sol-state colloid absorbed acid gas products from coal combustion, the pH value decreased and a large amount of Ca2+ in Ca-Bt precipitated, thus immediately growing calcium bridges with LMP molecules that formed a three-dimensional network structure for gelation. The optimum ratio of the new colloid was determined through X-ray diffraction, tube inversion, shock shear-temperature scanning, and genetic algorithm. By testing the fire extinguishing performance of the colloid, the findings proved that the product had good oxygen isolation performance, strong adhesion ability, high thermal stability, and strong inhibition effects on coal combustion. [ABSTRACT FROM AUTHOR]

Thermal runaway initiated in an individual cell may transfer heat to adjacent cells, and cause thermal runaway propagation. Thus, mitigation and prevention of thermal runaway propagation using extinguishing agents are significant. In this work, fire and extinguishing tests on 117 Ah LIBs with Li(Ni 0.8 Co 0.1 Mn 0.1)O 2 (NCM)/graphite electrodes are investigated. The suppression effects of different extinguishing agents including HFC-227ea, C 6 F 12 O and water spray on thermal runaway propagation in confined space were compared. Results show that thermal runaway propagation can occur in LIBs module even with thermal management measures. When activated immediately after the thermal runaway of the first cell, each agent can extinguish the LIBs module fire. However, the cooling capacity of extinguishing agent is the key factor to suppress thermal runaway propagation. The heat dissipation of HFC-227ea, C 6 F 12 O and water spray in fire extinguishing test is 24.8 kJ, 111 kJ and 459.8 kJ, respectively. Thus, HFC-227ea can hardly suppress the thermal runaway propagation. Although C 6 F 12 O can not prevent thermal runaway propagation, it can decrease the battery temperature, slow down the heat transfer rate and prolong the propagation time. While water spray has the best cooling effect, which can prevent thermal runaway propagation. [ABSTRACT FROM AUTHOR]

Gas chromatography (GC), ion chromatography (IC), and gas chromatography–mass spectrometry were used to investigate the thermal degradation of hexafluoropropane (HFC-236fa) fire suppression agent between 500 and 850 °C (GC–MS). The results show that the pyrolysis characteristics of HFC-236fa can only occur when the temperature is above 600 °C. The gas products of HFC-236fa pyrolysis mainly contain CHF3, CF2 = CHF, CF3C ≡ CCF3, and (CF3)2C = CF2. The concentration of each component is different with different pyrolysis temperatures and residence times. Moreover, the possible decomposition mechanism of HFC-236fa was proposed based on density functional theory, which was achieved via obtaining the activation energy and the details of dissociation pathways. By under the experimental studies and theoretical calculation, the pyrolysis of HFC-236fa was investigated. [ABSTRACT FROM AUTHOR]

During the thermal runaway process of lithium-ion batteries, the release of vaporized electrolyte and combustible gases can lead to the formation of a jet flame, posing a significant fire or explosion risk. In order to deal with the threat of lithium-ion battery vent gas fires to the safety of energy storage power stations, it's crucial to identify effective fire extinguishing agents for lithium-ion battery systems. This study employs a combination of experimental and numerical simulation methods to assess the suppression capabilities of CO 2 , N 2 , and HFC-227ea on vent gas/air premixed flames originating from lithium-ion batteries with various cathode materials. Laminar flame speed of vent gas/air/extinguishing agent premixed flames at specific equivalence ratios were measured using a Bunsen burner device under ambient temperature and atmospheric pressure conditions. Additionally, numerical calculations of laminar flame speed and adiabatic flame temperature were conducted using CHEMKIN-Pro, accompanied by an analysis of the chemical inhibition mechanism of HFC-227ea. The findings reveal that although HFC-227ea may slightly elevate the adiabatic flame temperature at lower equivalence ratios, its overall fire extinguishing efficacy surpasses that of CO 2 and N 2. These results offer valuable insights for selecting appropriate fire extinguishing agents for energy storage power stations, thereby enhancing the safety standards of energy storage systems. [ABSTRACT FROM AUTHOR]

To address the instability and limited fire-suppression effectiveness of foam agents, a three-phase gel foam incorporating α-olefin sulfonate (AOS), alkylphenol ethoxylates (OP-10), modified bentonite, and cellulose gel was developed. The foam formula was optimized by using response surface method. Combined with Zeta potential and FTIR, the intrinsic interaction between materials was analyzed. The foam decay process, liquid discharge regularity, and viscosity change under different additives were compared. The enhancement of its fire extinguishing ability was explored. Results show that: The optimized foam achieves optimal foaming volume and half-life. Surfactant adsorption reduces the surface charge of particles and stabilizes their dispersion in liquid membrane. Cellulose is wound between particles to form a stable absorbent skeleton and delay decay of foam. Foam adheres stably to solids and covers them with barrier, inhibiting wood burning. The time to extinguish wood stack fire was 84 s, a 36.84% improvement over Class A foam extinguishing agents. [Display omitted] • A new three-phase-gel foam fire extinguishing agent was developed by using particle-gel crosslinking technology. • The mechanism of particle-gel crosslinking and stabilization was elucidated. • The foam extinguishing capability was characterized in the field. [ABSTRACT FROM AUTHOR]

The environmentally friendly fluorine-free fire extinguishing agent based on the silicone surfactant was developed in order to solve the environmental hazards and bio-accumulative of traditional aqueous film-forming foam (AFFF). The carboxyl modified polyether polysiloxane surfactant (CMPS) was an efficient alternative to fluorocarbon surfactant, which was firstly synthesized via the esterification reaction using hydroxyl-containing polyether modified polysiloxane (HPMS) and maleic anhydride (MA) as raw materials. Then the surface activity, foam properties, micellar morphology of the CMPS and four hydrocarbon surfactants, as well as their mixture are evaluated by surface tension, Ross-Miles and cryo-transmission electron microscopy (Cryo-TEM). And the suitable key amount of CMPS and hydrocarbon surfactants added to the extinguishing agent were optimized by orthogonal tests. Moreover, the effect of foam stabilizer on the surface activity, foam property and fire extinguishing performance of fire extinguishing agent are also analyzed. Consequently, a new environmentally friendly fluorine-free fire extinguishing agent was prepared and the surface tension, the interfacial tension, foam properties, bubble morphology, spreading behavior and fire extinguishing mechanism were systematically characterized. The Cryo-TEM results illustrate that the intense interaction among silicone and hydrocarbon molecules exists in the the mixture of CMPS and hydrocarbon surfactants, which is produced through the change of micellar morphology, i.e. microscopic larger spheroidal micelles of CMPS transited to smaller spheroidal micelles and wormlike micelles in the mixed system. The surface tension of synthesized foam extinguishing agent is 22.3 mN/m and the spread coefficient is 0.9 mN/m, which has excellent surface activity and spreading property. The prepared foam extinguishing agent exhibits superior fire-fighting property, which can be attributed to the high surface activity, good foam property and superior foam stability. The research results of this paper lay a theoretical foundation for the research and development of efficient environmentally friendly foam extinguishing agent. [Display omitted] • CMPS was successfully synthesized via esterification reaction. • CMPS surfactant has superior surface activity, foaming ability and foam stability. • The percent of CMPS and hydrocarbon surfactants were optimized by orthogonal tests. • Synergistic effect between CMPS and hydrocarbon improves extinguishing performance. • Foam stabilizer affects the physical-chemical property and extinguishing performance. [ABSTRACT FROM AUTHOR]