Fire Extinguishing Research Articles

Study on preparation and thermal insulation properties of curing foam

The thermal insulation performance of curing foam is a critical factor affecting fire extinguishing efficiency. In this study, sodium dodecyl sulfate was used as the foaming agent, and then combined with foam stabilizers, foam thickeners and inorganic powders to prepare the curing foam extinguishing agents. The result demonstrated that the addition of PEG and Xanthan gum could prolonge the 50 % drainage time of foam solution to 1.98 times compared with the foam solution without foam additives. The composite powders imparts an excellent thermal insulation and high-temperature stability to curing foam, especially the mass fractionratio of loess to cement equals to 4:6 and the water cement ratio is 0.7. Moreover, the thermal insulation tests showed that when the test temperature equalled 500 °C, the curing foam could reduce the temperature of the covered surface by 234.2 °C. Compared with the water-based foam, the thermal insulation performance was improved by 58.1 %. Finally, fire extinguishing test showed that the fire extinguishing time of curing foam is 0.47 s and 33.99 s shorter than that of water-based foam and water, respectively. The consumption of water-based foam and water fire extinguishing consumption is 1.46 times and 4.37 times that of curing foam, respectively. The excellent structural stability is due to the addition of Xanthan gum and PEG additives, which provide a more uniform distribution of bubbles and denser pores. At the same time, the mixture of loess and cement acts as a skeleton in curing foam thereby improving the stability of the integral structure and further preventing the heat transfer.

Fire Extinguishing Technology Ssing Borehole Drilling In Closed Fire Zones of Coal Mines

Fire Extinguishing Technology Ssing Borehole Drilling In Closed Fire Zones of Coal Mines

A novel phosphogypsum based self-produced gas expansion slurry for preventing coal spontaneous combustion

In order to solve the coal spontaneous combustion disaster in the upper layer goaf during the slicing mining process, a slurry that can expand by self-produced gas was developed using phosphogypsum and sodium bicarbonate as raw materials. The effect of different factors on the performance of phosphogypsum based self-produced gas expansion slurry (PSES) was analyzed. The optimal ratio and conditions of PSES were determined through orthogonal experiments. The thermal insulation performance and cooling and fire extinguishing performance of PSES were studied. Finally, it was applied in Luwa coal mine in Shandong province. The research results indicated that the optimal experimental conditions and ratios for PSES were phosphogypsum content of 56 wt%, sodium bicarbonate content of 21 wt%, water temperature of 25 ℃, and mixing time of 65 s. Under these conditions, the expansion performance of the slurry was good, and the setting time and compressive strength can meet the requirements for sealing the coal and rock cracks in the goaf. Under the same heat source, the thicker the slurry, the better its thermal insulation effect. Under the same thickness, the higher the heat source temperature, the shorter the effective insulation time(EIT). After the slurry was injected into the cracks of the broken coal, it wrapped around the broken coal from bottom to top. The temperatures of A-layer, B-layer, and C-layer of the coal pile decreased in sequence. After half an hour of grouting, the temperatures at all points dropped below 50 ℃ without any reignition phenomenon. After injecting PSES into the coal spontaneous combustion dangerous area in the upper layer goaf, the concentrations of CO and O2 in the monitoring borehole decreased to a safe range, and the generated CO2 concentration finally stabilized at around 4.6 %. It showed that PSES can seal the coal and rock cracks in the goaf, suppress the coal spontaneous combustion, and guarantee the lower layer working face can be mined.

The Impact of Persuasive Communication, Transformational Leaderships, and Work Interest on Work Ethic

The Yogyakarta City Fire Department is located on Jl. Muja Muju. Umbulharjo, Yogyakarta City, is an implementing element of the government that has the responsibility of assisting the community in handling fires and rescues. In addition to extinguishing fires, firefighters are also trained to carry out evacuations such as accidents, natural disasters, and other emergency evacuations. So the importance of competent and qualified human resources (HR) is needed to support the work ethic and activities so that the mission of the company or an organization can succeed. This study aims to prove and collect empirical evidence that Persuasive Communication, Transformational Leadership, and Work Interest affect the Work Ethic of Employees of the Fire and Rescue Service of Yogyakarta City. By conducting this study, the researcher hopes that the results of this study can be an evaluation in improving the performance and work ethic of the relevant agencies. This type of quantitative research with 67 respondents, using a purposive sampling method. Data was collected using a questionnaire and Likert scale as a measurement. The results of the study partially and simultaneously all variables, namely Persuasive Communication, Transformational Leadership, and Work Interest, have a positive and significant effect on the Work Ethic.

Study on preparation and properties of steel slag based composite gel for mine fire prevention and extinguishing

A novel fire-preventing composite gel, mainly made from steel slag (SS) and silica fume (SF), was created for a coal mine’s spontaneous combustion. The gelation mechanism of the steel slag-based composite gel (SSG) was investigated using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and field emission scanning electron microscopy (SEM). The findings suggest that SSG is generated through the processes of hydration and geopolymerization involving SS and SF. And in the alkaline milieu of a 1.5 M water glass solution, SSG manifests enhanced strength and water retention capacities. Moreover, the fire prevention and extinguishing performance of the SSG was analyzed and verified using low-temperature oxidation, thermogravimetry, and low temperature nitrogen adsorption experiment (LTNA). The SSG has proven highly effective in suppressing spontaneous coal combustion by inhibiting CO production, raising the coal oxidation temperature, and reducing the contact area between oxygen and the coal body.

Perancangan Jalur Evakuasi Kebakaran PT. PCC dengan Metode Algoritma Dijkstra

Fires can occur at any time, therefore a mechanism is needed to evacuate the building in the event of a disaster. Generally, public facilities provide instructions and evacuation routes for exiting the building. PT. PCC has its headquarters in Australia. As for PT. PCC also opened a new factory located in Gresik Regency, East Java. The new factory does not yet have adequate fire evacuation routes. Even though inside the building there are materials and equipment that are flammable. Based on this, this research aims to design fire evacuation routes in PT buildings. PCC Gresik. The type of research used in this research is quantitative research. The method that the author applies is the Djikstra Algorithm to determine the shortest proposed route. The design of the evacuation route has 2 gathering points, namely at the front and back. There are 22 evacuation route signs, 6 exit signs, 2 gathering point signs, 2 emergency telephone signs and 10 Light Fire Extinguisher (APAR) signs. Evacuation route signs, exit signs and Light Fire Extinguisher (APAR) signs are planned to be installed on the walls. Assembly point signs and emergency telephone signs are installed on poles.

Analysis of the Influence of Nozzle Structure of Dry Powder Fire Extinguishing System on Supersonic Jet Characteristics

Analysis of the Influence of Nozzle Structure of Dry Powder Fire Extinguishing System on Supersonic Jet Characteristics

Experimental study of the strategy of C6F12O and water mist intermittent spray to suppress lithium-ion batteries thermal runaway propagation

Extinguished lithium-ion battery fires can experience temperature rebound and re-ignition, necessitating proper fire extinguishing and cooling measures for battery safety. This study introduces a novel approach that integrates C6F12O and water mist as a strategy to prevent the spread of thermal runaway in lithium-ion batteries, evaluating the fire-suppression and cooling ability under various intermittent spray modes. The findings demonstrate that the strategy has a stronger suppression effect compared to continuous water spray and could prevent the spread of thermal runaway. C6F12O can extinguish fires in just 1 s. During the cooling phase, the cooling capacity generally decreases with increasing cycle period and duty cycle. Among different cycle periods, C6F12O combined with intermittent water mist spray (DC = 0.5, Pt = 2 s) exhibited the most effective cooling, significantly reducing peak temperature and providing the highest heat suppression. In terms of duty cycles, C6F12O combined with intermittent water mist spray (DC = 0.1, Pt = 20 s) achieved the longest cooling duration, lowering the temperature of Cell #3 to below 50 °C. The combination of C6F12O and intermittent water mist spray rapidly extinguishes flames, maximizes the cooling impact of water mist, and ultimately hinders the propagation of thermal runaway.

Development of a Graded Early Warning Index System and Identification of Critical Temperatures for Coal Spontaneous Combustion Using Composite Gas Characteristics.

Conventional single gas alarm method and coal spontaneous combustion three-stage alarm method have become increasingly inadequate to meet complex underground conditions. To address this issue, this study focuses on the coal in the goaf of the Z109 working face in the Donggucheng Mine as the research object. Through program-controlled heating experiments, the production of carbon monoxide and hydrocarbon gases during the coal oxidation process was determined, and the variation characteristics of gas ratios with temperature were further analyzed. The coal spontaneous combustion process was subdivided into seven small stages, and a quantitative composite parameter coal spontaneous combustion grading warning system was formulated. Based on its characteristics, measures to be taken under different warning levels were proposed, and it was determined that 120, 140, and 160 °C are the key temperatures for coal spontaneous combustion prevention and control in the Z109 working face of Donggucheng Mine. By using numerical simulation, the optimal nitrogen injection position for the working face was determined and the on-site fire prevention and extinguishing measures were optimized, providing insights into the establishment of a coal mine spontaneous combustion warning system.

Research on the technology of uniformly injecting nitrogen into the porous long pipes in the gob of the gob-side entry retaining mining mode with roof cutting and pressure relief

The implementation of the Gob-Side Entry Retaining Mining Mode with Roof Cutting and Pressure Relief (GERRCPR) results in the gob connecting to the retaining roadway, creating an open space that causes significant air leakage and increases the risk of spontaneous combustion. A study was conducted during the implementation of the GERRCPR in the Xiaonan Coal Mine N1-1502 working face to investigate spontaneous combustion characteristics, along with fire prevention and extinguishing measures. To analyze gob airflow, Computational Fluid Dynamics (CFD) was employed to collect data on airflow conditions, O2 concentration, and temperature. Based on this, this study focuses on exploring the effects of nitrogen injection treatment under various rates and positions to optimize parameters for buried pipe nitrogen injection. Results indicated that within the GERRCPR, air leakage in the gob increased, leading to an increase in O2 concentration, expansion of the oxidation zone, and an elevated risk of spontaneous combustion. Air leakage primarily occurred from the retaining roadway and the working face near the intake-air roadway, peaking at a retaining roadway length of 500 m, with a flow rate of 226 m3/min. Following nitrogen injection treatment, the oxidation zone was significantly reduced, with optimal treatment achieved at a nitrogen injection depth of 70 m and a rate of 600 m3/h. Field monitoring data showed that the inertization measure of using porous long pipes, a nitrogen injection spacing of 30 m, and a nitrogen injection rate of 600 m3/h significantly decreased the O2 concentration within the gob. This reduction meets safety production requirements and outperforms the effectiveness of traditional buried-pipe nitrogen injection methods, thereby validating the simulation accuracy. Understanding the laws governing spontaneous coal combustion in the GERRCPR and enacting preventive measures for nitrogen injection can improve safety standards in mining operations. This proactive approach can effectively prevent spontaneous coal combustion accidents, resulting in substantial social benefits.

Experimental study on the selection of coal-to-oil gasification ash slag gel gelling agent

The gasification ash slag (GAS) is a solid waste that is difficult to degrade and causes serious environmental pollution. In this study, a new type of mine fire prevention and extinguishing gel material was prepared from gasified ash as a base material for spontaneous combustion control of coal in the mining airspace. To better enhance the gel fire prevention process pipeline conveying efficiency, and fire extinguishing performance, the selection of seven gelling agent formulation gasification slag gel, through the thermal stability, water retention, and rheological experiments preferred the best performance of the gelling agent. Thermal stability experiments showed that the thermal decomposition of the gel was divided into three stages: water loss, gel decomposition, and secondary decomposition of decomposition products, and the analysis of the initial decomposition temperature and mass loss rate yielded the best thermal stability of CB-GAS; Water retention experiments show that XG-GAS still retains 72.33 % of water at the 11 h in high-temperature environment, which is the best water retention performance; The rheological experiments showed that the viscosity of the gel decreased continuously with the increase of shear stress, and the analysis of the parameters yielded the best rheological properties of CB-GAS. Combining the four performance indicators, the hierarchical analysis method was used to calculate the influence weight value of the indicators and carry out comprehensive scoring, which resulted in the best performance of the gasification ash fireproofing gel prepared with the optimal gelling agent CB, followed in order by XG, CMC, HPG, MC, SA, and HPMC. This study provides an important reference for gel grouting fireproofing.

Management of natural disasters in the environment PT. Mutiara Masyhur Sejahtera, with the formation of an emergency response team

Background: Sidoarjo Regency, East Java, is often hit by tornadoes that cause material losses and injuries, especially at PT. Mutiara Masyhur Sejahtera located at Jalan Kahuripan Raya No. 9-11, Entalsewu, Buduran, Sidoarjo. This phenomenon encourages the need to improve disaster preparedness and response. Method: This study uses a qualitative descriptive approach with primary data collection through direct observation and in-depth interviews with the company's Project Manager. Secondary data covering organizational structure and number of employees are also used. Data is analyzed through a reduction process to ensure relevant and accurate information. Findings: Although PT. Mutiara Masyhur Sejahtera already has fire protection equipment, such as Light Fire Extinguishers (APAR), but there is no system or policy that regulates emergency response management for fires or other disasters. Forming an Emergency Response Team and creating Procedures and Work Instructions (IKA) regarding Emergency Response are needed as a reference when an emergency occurs. Conclusion: To improve disaster preparedness, companies must equip themselves with an occupational safety and health management system (SMK3) that regulates all compliance related to K3 aspects. This aims to prevent work accidents and occupational diseases, reduce the negative impact of disasters and improve overall work safety. Novelty/Originality of this study: This study presents a new approach to improving disaster preparedness in the private sector, especially for companies operating in disaster-prone areas such as Sidoarjo. This study proposes the integration of an occupational safety and health management system (OHSMS) with a particular focus on disaster emergency response management, which can be a model for other companies in improving disaster resilience.

Tuning stability, rheology, and fire-extinguishing performance of advanced firefighting foam material by inorganic nanoparticle flame retardants

HypothesisNanoparticle-stabilized foams are extremely stable, and flame retardant inorganic nanoparticles should be able to add sealing capacity of firefighting foams on flammable liquid fuels, and hence enhance fire extinguishment performance on liquid fuel fire. In practice, how do flame retardant nanoparticles resist the destructive effect of oil molecules on foam and tune foam properties? ExperimentsWe have prepared a nanoparticle-enhanced foam comprising of hydrocarbon surfactant, short-chain fluorocarbon surfactant, and nanoparticles. The interactions among nanoparticles and surfactant molecules were characterized by using dynamic surface tension and conductivity. Stability, rheology, and oil resistivity on liquid fuel of the nanoparticle-enhanced foam were evaluated systematically. Fire suppression effectiveness of the foams was verified based on a standard experiment. FindingsFoam stability and oil resistivity were enhanced due to self-assembled network structures formed by jammed aggregates composed by nanoparticles and surfactants in Plateau borders and bubble films, providing structural recoverability and enhanced viscoelasticity within foam. Foams containing nano-SiO2, nano-CaCO3, nano-Al(OH)3, and nano-Mg(OH)2 show difference in fire extinguishment due to different ability to enhance foam properties. Foam containing nano-Al(OH)3 shows the strongest adaptation and could shorten fire extinguishing time by 2 times and prolong burn-back time by 2.3 times compared with commercial product.

Suppression effects of different extinguishing agents on vent gases fires from lithium-ion batteries after thermal runaway: A comprehensive experimental and numerical study

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 CO2, N2, 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 CO2 and N2. 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.

RELATIVE IMPORTANCE INDEX OF LEADING INDICATORS FIRE PROTECTION SYSTEMS IN HIGHER EDUCATION BUILDINGS IN KOTA BANDA ACEH

Fire can cause material loss and also cause physical disabilities and even fatalities for building users. Fires that occur as a result of human activity must be overcome by increasing human awareness themselves. However, fires caused by natural factors or errors in the electrical system can be overcome by having a fire prevention system or safety system. The aim of the research is to identify the main indicators of fire protection systems in educational buildings in Banda Aceh City. A closed questionnaire and Likert scale survey of respondents using educational buildings was conducted to collect data. Next, the data is processed using the frequency index analysis method and the Relative Importance Index (RII). The results of the frequency index analysis provide an overview of the percentage level of occurrence of the fire protection system variable, namely the acid detector, at 91.294%. Based on the results of the RII analysis, five main indicators were found that influence the safety system, namely light fire extinguishers (0.929), smoke detectors (0.913), water transmitters (0.911), standpipes (0.894), and fire hydrant systems (0.892). Meanwhile, the main variable for the fire protection system is the active protection system with a RII value of 0.889.

Analisis Disiplin Kerja Pada CV Arsana Sentosa

The purpose of this research is to understand the process of employee discipline at CV. Arsana Sentosa, identify barriers in the implementation of employee discipline, and find ways to overcome these barriers. The method used is qualitative descriptive analysis. The analysis results show that the implementation of Standard Operational Procedures (SOP) at CV. Arsana Sentosa provides significant benefits if done properly according to their functions. If employee discipline at CV. Arsana Sentosa decreases, the profit obtained will also decrease, even leading to losses. From previous discussions, it can be concluded that the implementation of discipline at CV. Arsana Sentosa, particularly in the use of fire extinguisher cylinders, has a significant impact if employees implement discipline well. This can be seen from the discipline system at CV. Arsana Sentosa, which is in line with the applicable regulations. However, there are still things that need to be improved, such as employees needing to have principles in managing time and being perfectionists without delaying tasks.

3D Hand Motion Generation for VR Interactions Using a Haptic Data Glove

Recently, VR-based training applications have become popular and promising, as they can simulate real-world situations in a safe, repeatable, and cost-effective way. For immersive simulations, various input devices have been designed and proposed to increase the effectiveness of training. In this study, we developed a novel device that generates 3D hand motion data and provides haptic force feedback for VR interactions. The proposed device can track 3D hand positions using a combination of the global position estimation of ultrasonic sensors and the hand pose estimation of inertial sensors in real time. For haptic feedback, shape–memory alloy (SMA) actuators were designed to provide kinesthetic forces and an efficient power control without an overheat problem. Our device improves upon the shortcomings of existing commercial devices in tracking and haptic capabilities such that it can track global 3D positions and estimate hand poses in a VR space without using an external suit or tracker. For better flexibility in handling and feeling physical objects compared to exoskeleton-based devices, we introduced an SMA-based actuator to control haptic forces. Overall, our device was designed and implemented as a lighter and less bulky glove which provides comparable accuracy and performance in generating 3D hand motion data for a VR training application (i.e., the use of a fire extinguisher), as demonstrated in the experimental results.

Comparative study on fire suppression of NCA18650 lithium-ion battery by several fire extinguishing agents

Comparative study on fire suppression of NCA18650 lithium-ion battery by several fire extinguishing agents

Combustion and extinction characteristics of an ethanol pool fire perturbed by low–frequency acoustic waves

To study combustion and extinction characteristics of flames perturbed by acoustic waves, the evolution of the shape of the pool fire, mass loss rate (ma′) of fuel, and mechanisms of extinction of the flames under acoustic perturbations were studied. Moreover, based on parameters of combustion characteristics of flames, parametric models of ma′ and flame extinction were developed. The research results demonstrate that the shapes of unperturbed flames change during combustion, however, when perturbed by acoustic waves, the flame shapes become irregular and the flame fronts become disorderly. Compared with the combustion of unperturbed flames, ma′ is increased under acoustic perturbation. There are upper and lower limits for the change of ma′, so the models of upper and lower limits of ma′ in the concentrated area were established. Low–frequency acoustic waves tend to extinguish the pool fire, and the increased distance of acoustic response and acoustic source power can promote flame extinction. A linear relationship between flame extinction and acoustic frequency was semi-quantitatively characterized by a modified Damköhler (Da*) number. Based on the critical oscillation–induced displacement for extinguishing a pool fire, local acoustic parameters were characterized, and a critical model for local displacement during the extinction of the pool fire was established.

СРЕДСТВА ПОЛУЧЕНИЯ И ПЕРСПЕКТИВЫ ПРИМЕНЕНИЯ КОМПРЕССИОННОЙ ПЕНЫ В ПОЖАРОТУШЕНИИ

The subject of the article is modern fire extinguishing technologies based on compression foam. The purpose of the study is to study the means of obtaining and the prospects for using compression foam in fire fighting. Methods: analysis and synthesis, modeling. The results obtained indicate that compression foam has a number of advantages compared to water and conventional air-aspirated foam, so it can be used to extinguish fires in many industries and areas. A diagram of the production of compression foam is presented (the foam concentrate acts as a foaming agent) and a diagram of an autonomous installation for the production of compression foam. It is noted that one of the significant advantages of CAFS is the ability to create a finished product that matches a specific type of fuel or a specific situation. The characteristics of the SmartCAFS product have been defined. A typology of the use of compression foam depending on the type of incident is presented. The results of fire resistance tests of various foams are presented. It is concluded that fire suppression systems using compression foam have significant advantages, such as minimizing the spread of fire, the volume of water required to cover large areas, costs and placement, and the integration of CAFS with digital technologies.