• Fire Science and Engineering
• /
• v.28 no.2
• /
• pp.20-25
• /
• 2014

In this study, the extinguishing performance evaluation of wetting agent for wood crib was conducted by using a scale model equipment that we designed. To confirm the optimal conditions of the experiment, a test was changed amount of fire extinguishing water and the number of timber. As a result, the discrimination of the fire extinguishing performance was seen only when 20 pieces of wood and the extinguishing water of 100 mL were used. After evaluating the extinguishing performance of domestic and foreign wetting extinguishing agents under these conditions, a reignition was occurred in only when we used water. In addition, the discrimination of extinguishing performance was seen through the temperature distribution according to the time of watering. Based on the results of this experiment, this study is expected to be able to use as a basis on presenting a method of optimized performance evaluation of wetting extinguishing agent.

• Fire Science and Engineering
• /
• v.26 no.6
• /
• pp.1-6
• /
• 2012

There are specific indications about additional gas for the unencloseable openings of the carbon dioxide extinguishing systems. But there are no indications for other gas extinguishing systems including clean agent extinguishing systems only have the principle when it need, apply it. Therefore, this study suggested applying the equation of additional gas for the unencloseable openings of the carbon dioxide to all of the other fire suppression gas that we are use.

• Fire Science and Engineering
• /
• v.15 no.1
• /
• pp.34-40
• /
• 2001

Fire extinguishing efficiency of mixed gaseous agents were investigated by the cup-burner test and predicting by the model of flame extinguishing concentration. The binary mixed agents that tested were carbon dioxide/HFC-23, carbon dioxide/HCFC-22, carbon dioxide/HFC-227ea, carbon dioxide/HFC-125, carbon dioxide/FIC-13I1, Hexafluoropropylene/HFC-23 and ternary mixed agents were carbon dioxide/HFC-23/HFC-l34a, carbon dioxide/HFC-23/HFC-227ea, carbon dioxide/HFC-23/HFC-125. A model which contains the flame extinguishing concentration and composition of pure components predicted the flame extinguishing concentration of mixture well. This model was superior when each component of the mixture exhibit physical fire extinguishing performance.

• Journal of the Society of Disaster Information
• /
• v.15 no.3
• /
• pp.402-408
• /
• 2019

Purpose: The study want to verify application the medium expantion foam extinguisher of expantion foam rate and fire extinguishing Performance test because the medium expansion system can maintain the discharge distance less affected by air currents, and the foam agent can be used efficiently. Method: For the study, the medium-expansion testing apparatus was manufactured and with synthetic surfactant foam agent of (class B) fire extinguishing model, and Fire Performance was analyzed for foam expansion rate and the fire agent consumption was measured and analyzed. Results: We measured the medium-spray testing apparatus and found that the expansion rate was 26.1 times. The test results of a 20-unit fire extinguishing model show that the extinguishing time is faster than the high and low foam expansion. It has been analyzed that it is possible to apply a hand-operated with a hose reel or medium expansion apparatus. Conclusion: Considering that the foaming agent and the extinguishing performance of the medium foam ratio are excellent, It is necessary to introduce the technical standards of medium foam agent for the introduction of hand-operated equipment, such as hose reel or portable medium foam apparatus.

• Journal of the Korean Society of Safety
• /
• v.28 no.6
• /
• pp.23-28
• /
• 2013

In order to improve extinguishing performance of water mist, many studies of additives have been conducted. In this study, viscosity agent which has the ability to improve extinguishing performance by adhering to the surface on fire was used and fluorine-free surfactant was also added to water to enhance water's wetting ability. This study aimed to verify optimal concentration of extinguishing of additives according to fire source and extinguishing performance by comparison with pure water. In case of wood crib fire, the results show that flame suppression and extinguishing time of sodium alginate 0.4 wt.% are 3.4 times and 2.2 times shorter than those of pure water in 0.2 MPa respectively. It seems that large amount of water adhere to surface on fire, thus cooling effect on surface was enhanced. Also water consumption of sodium alginate 0.4wt.% is up to 65% lower than that of pure water. In case of heptane fire, extinguishing time of cocobetaine 0.1 wt.% is 9.7 times shorter than that of pure water in 0.2 MPa. It is thought that because cocobetaine can block oxygen and suppress oil mist by making emulsion film on fire surface due to a low surface tension. On the other hand, water consumption of cocobetaine 0.1 wt.% is 92% lower than that of pure water.

• Fire Science and Engineering
• /
• v.16 no.3
• /
• pp.77-83
• /
• 2002

We measured flame extinguishing concentration and flue gas composition in the n-heptane fuel cup-burner system using inert gas agents such as nitrogen, argon, carbon dioxide and their mixtures. The flame extinguishing concentration of binary gaseous mixture was well predicted by model which contains the flame extinguishing concentration and composition of pure components. The higher average specific gravity of the mixed inert gas agents, the more excellent flame extinguishing performance. And the structure of enclosed space also affects the fire extinguishing. The composition of carbon dioxide in the flue gas was decreased with increasing extinguishing agent used. Nitrogen monoxide production is not related with increasing nitrogen, but increased at rapid mass flow rate of air in the cup-burner.

• Fire Science and Engineering
• /
• v.28 no.4
• /
• pp.1-7
• /
• 2014

Several complex devices and equipments are installed in the car's engine room, including various kind of oils or other flammable materials. So re-ignition is very likely to take place in it. In addition, it is restrictive for the driver or the occupant to open the bonnet and to spray the fire extinguisher in the engine room due to the high possibility of explosion. Therefore, a fire extinguishing system, which can detect a fire and inject the fire extinguishing agent to extinguish it, and fire extinguishing agents including HFC-227ea, which can stand the high temperature within the engine room and hold the viscosity sufficient to keep it in the kind of foam, were developed and tested. And the suffocation effect and the cooling effect come from the fire extinguishing principle of the foam fire extinguishing agent and the inhibiter catalyst effect come from the one of HFC-227ea was led simultaneously, and fire extinguishing agents without the secondary damage caused by residuals after the fire extinguishment like a case of the powder fire extinguishing agent, were developed. And experiments using a vehicle collision after the discharge is complete, foreign material can be removed without extinguishing the advantage that experimental results obtained.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
• /
• 1996.11a
• /
• pp.57-61
• /
• 1996

Our goal was to make a cost-effective automatic fire extinguishing system for the engine compartment use of automobiles. We designed this system for the engine compartment. This system consists of 1)foam extinguisher, 2)four nozzles, 3)a pipe arrangement, and 4)an extinguishing device which is equipped with a glass bulb as detector. First and foremost, the extinguishing device was carefully designed to keep the system cost to a minimum. Second, a AFFF foam extinguisher was used because no other fire-fighting agents proved effective against fire in the engine compartment. The AFFF(Aqueous Film Forming Foam) agent which was used in the extinguisher is the 3M company's Light Water. We sought, however, to make other foams by using Halon 1301 and Halon alternatives such as HCFC Blend A, HFC-227ea. We selected these alternatives instead of air in order to raise the expansion ratio of the AFFF agent. By these means we discovered that it is possible to increase the expansion ration of the AFFF agent up to 44:1. We then demonstrated that our automatic fire extinguishing system is the most effective and lowest cost-system yet devised for passenger cars.

• Journal of the Korean Society of Safety
• /
• v.30 no.4
• /
• pp.79-85
• /
• 2015

Onboard fire extinguishing system is important to protect cargo and human lives and every oil tanker has foam type fire extinguishing system. Because of environmental problem, agent which contains materials such as Perfluorinated compounds are regulated and the development of the environmental friendly agent is required. The protein foam has less environmental pollution problem and has an excellent fire extinguish performance to oil fire. In the research, bivalency metal salts were added as stabilizer to increase fire resistance and stability of the foam. Ferrous sulfate, Iron chloride and Nickel chloride were used and to adjust to vessel, sea water was applied. As a stabilizer increased, the expansion ratio was raised. However 25% drainage time was decreased over 2.0 wt.% which is knowable that the foam brokes easily. The amount of generated foam was measured to check fluidity of foam and it appeared that when $FeSO_4$ 1.2 wt.% was added, the amount of generated foam reached large and also the 25% drainage time was high. To evaluate the fire extinguishing performance for oil fire, the small scale oil fire test was executed. When $FeSO_4$ 1.2 wt.% was added, fire extinguishing time was in its shortest which informs fluidity of foam and stability are important factors on fire extinguishing efficiency.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.34 no.1
• /
• pp.14-17
• /
• 2024

Objectives: This is a case of air exposure assessment conducted after researchers complained of headaches and odor due to residual substances from fire extinguishing agents spread throughout the laboratory due to a malfunction of the fire extinguishing facility. Methods: A component analysis was conducted on the residual substances of a fire extinguishing agent spread in a laboratory using Py-GC-MS (pyrolysis gas chromatography mass spectrometry) at the research institute's own central equipment research center. As a result of the component analysis, several types of substances were detected. Among these, five types of substances subject to work environment measurement in the aromatic hydrocarbon series, which can affect headaches and odor, were selected as substances subject to exposure assessment in the air, and the measurement and analysis methods of the target substances were conducted in accordance with the KOSHA Guide for each substance. Conclusions: The measurement results showed that all 5 types of substances were not detected at locations A, B, and C. This is believed to be the result of the residual substances in the fire extinguishing agent being measured when approximately two months had elapsed after being exposed to the test bench, and the substances already exposed had volatilized and disappeared. In this survey, it is believed that the measurement process is more important than the measurement results.