• Fire Science and Engineering
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• v.15 no.4
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• pp.34-40
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• 2001

The spontaneous ignition of hydroxypropyl methyl cellulose(HPMC) was investigated at constant ambient temperature in the oven and minimum ignition temperature of dust clouds with Godbret-Creenwald Furnace respectively, In the experiments of the vessel filled with sample. the larger the vessel was the lower the spontaneous ignition temperature and ambient temperature was calculated from the Frank-Kamenetskii thermal ignition theory. The minimum ignition temperature for the dust cloud state was found under 21% oxygen concentration. At the experiment with the change of oxygen concentration, HPMC was not ignite at 10% $O_2$and so the limiting oxygen concentration was obtained at 10%.

• Journal of the Korean Society of Safety
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• v.16 no.3
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• pp.83-88
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• 2001

This study was preformed by measuring the minimum ignition temperature of MBS according to the change of sample vessel size and the minimum ignition temperature of MBS dust cloud The minimum ignition temperature of MBS product decreased as the vessel size was large, and it was obtained in the range from $120.5^{\circ}C$ to $94.5^{\circ}C$ and the apparent activation energy was obtained with 32.94Kcal/mol. The minimum ignition temperature of MBS dust cloud was measured by using Godbert-Greenwald furnace and it was obtained at $407^{\circ}C$ with the sample of 0.4g in the air and the ignition of dust cloud was not occurred below 13% oxygen concentration.

• Journal of the Korean Society of Safety
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• v.7 no.4
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• pp.45-53
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• 1992

Sponataneous ignition characteristics for granulated activated carbon were observed by performing experiments at constant ambient temperature and varying the ambient temperature sinusoidally. In case of varying the ambient temperature sinusoidally, the amplitudes of temperature were 5$^{\circ}C$, 1$0^{\circ}C$ and 15$^{\circ}C$ respectively, and the period in each amplitude was varied at an interval of 30minutes from zero to 3hours. As the results of experiments at a constant ambient temperature, the critical spontaneous ignition temperature of the sample decreased as the sample vessel size increased. Apparent activation energy of the sample calculated from the Frank-Kamenetskii's thermal Ignition theory was 38.82［kca1/mo1］ In case of varying the ambient temperature sinusoidally, the critical spontaneous ignition tempera-ture was lower than that at the constant ambient temperature, and the minimum critical spontaneous ignition temperature decreased with the amplitude of heating sinusoidal curve. At the same amplitude, the critical spontaneous ignition temperature decreased until it reached the minimum point and then in-creased as the period increased.

• Journal of the Korean Society of Safety
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• v.19 no.1
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• pp.137-140
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• 2004

The minimum ignition temperature at which the dust cloud can spontaneously ignite is considered to be very important in industries to prevent explosion occurring in hot surfaces. This paper has dealt with the experimental study of the determination of minimum ignition temperature of Hydroxy Propyl Methyl Cellulose (HPMC) dust cloud. We have used the Godbert-Greenwald Furnace Apparatus to determine the ignition temperature and limiting oxyten concentration for dust could. The experimental determinations on the minimum ignition temperature were carried out with various particle size with nominal diameters 45, 75 and 106${\mu}m$. The limiting oxygen concentration of dust cloud was determinated for the smaller size(45${\mu}m$) HPMC. Minimum ignition temperature of dust cloud was at 364$^{\circ}C$ for the concentration of 2.5g/L in the air and became higher with the increasing of nitrogen concentration. It was also found that the ignition didn't occur when the oxygen concentration was below 10%, and limiting oxygen concentration is at 11%.

• Journal of the Korean Institute of Gas
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• v.17 no.5
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• pp.69-74
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• 2013

The study was conducted experimentally on characteristic of thermal decomposition and minimum ignition temperature of magnesium dusts. For this purpose, three different Mg dusts of mean diameter (38, 142, $567{\mu}m$) were used. Experimental investigations were conducted by using TGA(Thermo gravimetric analysis) and MIT(Minimum Ignition Temperature) apparatus made in accordance with IEC 61241-2-1 standard. As the results, temperature of weight gain in Mg dust layers increased with increasing of heating rates in air and, under the same heating rate condition, minimum ignition temperature increased with particle size. Also the MIT of suspended Mg dust clouds tended to increase with increasing of mean diameter.

• Journal of the Korean Solar Energy Society
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• v.36 no.2
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• pp.73-78
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• 2016

This study investigates the main factors of fire prevention, such as spontaneous ignition and flash point, while using Diehylene Glycol (DEG) as the antifreeze for automobile and industrial machines. Our results show the flash point of $142^{\circ}C$ and the minimum ignition temperature of $388^{\circ}C$ in the range of $130{\mu}{\ell}{\sim}150{\mu}{\ell}$. By increasing temperature to ignite in 1 second, an instantaneous ignition temperature of the sample is $569^{\circ}C$ in the sample amount of $140{\mu}{\ell}$.

• Journal of the Korea Safety Management & Science
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• v.11 no.1
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• pp.43-49
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• 2009

This study set three kinds of situation and observed the various states such as carbonization by experimenting damages by fire of electric iron. The results of this study are as follows: The fire did not occurred when the unpowered iron over mattress and cotton shirts was com busted completely by external flame because the temperature of surface of soleplate and mattress did not reach the minimum ignition energy and when the powered electric iron over mattress and cotton shirts was left for an hour with its temperature dial set to high because the temperature of combustibles did not reach the minimum ignition energy. The fire occurred when the electric iron in which the outer box, bi-metal switch, and temperature fuse were removed over mattress and cotton shirts was powered by through heater terminal, and then the electric iron, mattress, and cotton shirts were combusted by the fallen combustibles because the temperature of combustibles reached to the minimum ignition energy with the help of active transfer of heat.

• Fire Science and Engineering
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• v.11 no.2
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• pp.3-10
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• 1997

Attempts are being made to investigate temperatures dependence of minimum ignition energy (MIE) based on concept of quantity of heat and thermal ignition theory. Regression equations for predicting MIE by means of temperature variations on the basis of statistical and mathematical methods are proposed. This study is undertaken to learn what proposed method is satisfactory hydrocarbons(propane and pentane). The proposed method has been tested and compared sucessfully with previously reported data in various journal.

• Fire Science and Engineering
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• v.28 no.4
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• pp.8-13
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• 2014

In order to improve safety for hydrogen network infrastructure, the ignition temperature by hot wire was investigated for different hydrogen compositions in pipelines. The result shows that minimum temperature for ignition decreased with decreasing hydrogen composition. The minimum temperature was confirmed at a hydrogen composition of approximately 10 vol.%. The one of the reasons is supposed that buoyancy force should generate the convection of gas mixture. It was also found that humidity had a little effect on ignition temperature, flame temperature.

• Journal of the Korean Society of Safety
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• v.32 no.2
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• pp.66-71
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• 2017

The autoignition temperature (AIT) is crucial combustible characteristics which need attention in chemical process that handle hazardous materials. The AIT, also to as minimum spontaneous ignition temperature(MSIT), is the lowest temperature of a hot surface at which the substance will spontaneously ignite without any obvious sources of ignition such as a spark or flame. The AIT may be used as combustion property to specify operating, storage, and materials handling procedures for process safety. This study measured the AITs of n-propanol+acetic acid system from ignition delay time(time lag) by using ASTM E659 apparatus. The AITs of n-propanol and acetic acid which constituted binary system were $435^{\circ}C$ and $212^{\circ}C$, respectively. The experimental AITs of n-propanol+acetic acid system were a good agreement with the calculated AITs by the proposed equations with a few A.A.D.(average absolute deviation). In the case of n-propanol and acetic acid system, the minimum autoignition temperature behavior (MAITB), which is lower than the lower AIT, is shown among the two pure substances constituting the mixture.