• Journal of the Korean Society of Safety
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• v.22 no.5
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• pp.84-89
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• 2007

The lower explosion limit(LEL) is one of the major combustion properties used to determine the fire and explosion hazards of the combustible substances. In this study, the lower explosion limits of the ester compounds were predicted by using the normal boiling points and the flash points based on the liquid thermodynamic theory. As a results, the A.A.P.E.(average absolute percent error) and the A.A.D.(average absolute deviation) of the reported and the calculated the LEL for the ester are 8.80 vol% and 0.18 vol%, respectively and the coefficient of correlation was 0.965. From a given results, by the use of the proposed methodology, it is possible to predict the lower explosion limits of the other flammable materials.

• Journal of the Korean Society of Safety
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• v.24 no.5
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• pp.28-33
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• 2009

The thermochemical parameters for safe handling, storage, transport, operation and process design of flammable substances are explosion limit, flash point, autoignition temperatures(AITs), minimum oxygen concentration(MOC), heat of combustion etc.. Also it is necessary to know explosion limit at high temperature and pressure. For the safe handling of benzene, lower explosion limit(LEL) at $25^{\circ}C$, the temperature dependence of the explosion limits and flash point were investigated. And the AITs for benzene were experimented. By using the literatures data, the lower and upper explosion limits of benzene recommended 1.3 vol% and 8.0 vol%, respectively. This study measured relationship between the AITs and the ignition delay times by using ASTM E659-78 apparatus for benzene, and the experimental AIT of benzene was $583^{\circ}C$. The new equations for predicting the temperature dependence of the explosion limits of benzene is proposed. The values calculated by the proposed equations were a good agreement with the literature data.

• Fire Science and Engineering
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• v.26 no.4
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• pp.63-69
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• 2012

Explosion limit is one of the major combustion properties used to determine the fire and explosion hazards of the flammable substances. In this study, the lower explosion limit (LEL) and upper explosion limit (UEL) of organic halogenated hydrocarbons were predicted by using the heat of combustion and chemical stoichiometric coefficients. The calculated explosion limits by the proposed equations agreed with literature data within a few percent. From the given results, using the proposed methodology, it is possible to predict the explosion limits of the other organic halogenated hydrocarbons.

• Journal of the Korean Institute of Gas
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• v.15 no.4
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• pp.44-50
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• 2011

Explosion limit is one of the major combustion properties used to determine the fire and explosion hazards of the flammable substances. In this study, the lower explosion limit(LEL) and upper explosion limit(UEL) of ethers were predicted by using the heat of combustion and stoichiometric coefficients. The values calculated by the proposed equations agreed with literature data within a few percent. From the given results, using the proposed methodology, it is possible to predict the explosion limits of the other flammable ethers.

• Journal of the Korean Institute of Gas
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• v.16 no.5
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• pp.7-13
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• 2012

An experimental study has been done to investigate the explosion characteristics of aluminum powders with different sizes and concentrations in a 20 L spherical explosion vessel. Two different sizes of aluminum powder were used : $15.1{\mu}m$ and $34.8{\mu}m$ with a volume mean diameter. The results revealed that $15.1{\mu}m$ Al powder has a Lower explosion limit (LEL) of $40g/m^3$, a maximun explosion pressure ($P_{max}$) of 9.8 bar and a maximum rate of pressure rise ($[dP/dt]_{max}$) of 1852 bar/s, in $34.8{\mu}m$ Al powder, LEL of $70g/m^3$, $P_{max}$ of 7.9 bar and $[dP/dt]_{max}$ of 322 bar/s. The LEL of Al powders tended to increase with the increase of particle size. Also, it was found that the flame velocity calculated from the powder with $15.1{\mu}m$ was about 5 times higher than that of the powder of $34.8{\mu}m$.

• Journal of the Korean Society of Safety
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• v.19 no.3 s.67
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• pp.65-69
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• 2004

This study was performed with Hartmann type dust explosion apparatus and Godbert-Greenwald furnace apparatus in order to research the effect of temperature and humidity affecting LEL, minimum ignition temperature of Hydroxy Propyl Methyl Cellulose. The experimental determinations in the range between $20^{\circ}C\;and\;60^{\circ}C$ of temperature was not affected $LEL(180g/m^3)$ but LEL showed $200g/m^3\;and\;250g/m^3\;at\;80^{|circ}C\;and\;100^{\circ}C$. As the change of humidity LEL was $180g/m^3\;for\;50\%,\;200g/m^3\;for\;60\%\;and\;250g/m^3\;for\;70\%$ but dust explosion didn't occur over $80\%$. The ignition temperature of HPMC dust clouds was increased as increasing of humidity. So, the minimum ignition temperatures at $50\%,\;60\%,\;70\%\;80\%$ of humidity was $363^{\circ}C,\;375^{\circ}C,\;397^{\circ}C,\;405^{\circ}C$.

• Journal of the Korean Society of Safety
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• v.33 no.4
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• pp.8-14
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• 2018

In the industrial chemical process involving combustible materials, reliable safety data are required for design prevention, protection and mitigation measures. The accurate combustion properties are necessary to safely treatment, transportation and handling of flammable substances. The combustion parameters necessary for process safety are lower flash point, upper flash point, fire point, lower explosion limit(LEL), upper explosion limit(UEL)and autoignition temperature(AIT) etc.. However, the combustion properties suggested in the Material Safety Data Sheet (MSDS) are presented differently according to the literatures. In the chemical industries, tetralin which is widely used as a raw material of intermediate products, coating substances and rubber chemicals was selected. For safe handling of tetralin, the lower and flash point, the fire point, and the AIT were measured. The LEL and UEL of tetralin were calculated using the lower and upper flash point obtained in the experiment. The flash points of tetralin by using the Setaflash and Pensky-Martens closed-cup testers measured $70^{\circ}C$ and $76^{\circ}C$, respectively. The flash points of tetralin using the Tag and Cleveland open cup testers are measured $78^{\circ}C$ and $81^{\circ}C$, respectively. The AIT of the measured tetralin by the ASTM E659 apparatus was measured at $380^{\circ}C$. The LEL and UEL of tetralin measured by Setaflash closed-cup tester at $70^{\circ}C$ and $109^{\circ}C$ were calculated to be 1.02 vol% and 5.03 vol%, respectively. In this study, it was possible to predict the LEL and the UEL by using the lower and upper flash point of tetralin measured by Setasflash closed-cup tester. A new prediction method for the ignition delay time by the ignition temperature has been developed. It is possible to predict the ignition delay time at different ignition temperatures by the proposed model.

• Journal of the Korean Society of Safety
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• v.30 no.2
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• pp.21-26
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• 2015

For the safe handling of o-cresol, this study was investigated the explosion limits of o-cresol in the reference data. The flash points and AITs(auto-ignition temperatures) by ignition delay time were experimented. The lower flash points of o-cresol by using closed-cup tester were experimented in $77^{\circ}C$ and $80^{\circ}C$. The lower flash points of o-cresol by using open cup tester were experimented in $86^{\circ}C$ and $87^{\circ}C$. This study measured relationship between the AITs and the ignition delay times by using ASTM E659 tester for o-cresol. The AIT of o-cresol was experimented as $495^{\circ}C$. The lower explosion limit(LEL) by the measured the lower flash point for o-cresol was calculated as 1.27 Vol%.

• Korean Chemical Engineering Research
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• v.55 no.2
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• pp.190-194
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• 2017

The combustion properties for the prevention of the fire and explosion in the work place are flash point, explosion limit, autoignition temperature (AIT) etc.. The using of the corrective combustion properties of the MSDS (Material Safety Data Sheet) of the handling substance for the chemical process safety is very important. For the safe handling of benzyl alcohol which is widely used in the chemical industry, the flash point and the AIT were measured. And, the lower explosion limit (LEL) of benzyl alcohol was calculated by using the lower flash point which obtained in the experiment. The flash points of benzyl alcohol by using the Setaflash and Pensky-Martens closed-cup testers measured $90^{\circ}C$ and $93^{\circ}C$, respectively. The flash points of benzyl alcohol by using the Tag and Cleveland open cup testers are measured $97^{\circ}C$ and $100^{\circ}C$. The experimental AIT of benzyl alcohol by ASTM 659E tester was measured as $408^{\circ}C$. The LEL of benzyl alcohol measured by Setaflash closed-cup apparatus was calculated as 1.17 vol% at $90^{\circ}C$. In this study, it was to possible predict the LEL by using the lower flash point of benzyl alcohol which measured by Setaflash closed-cup tester.

• Fire Science and Engineering
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• v.28 no.2
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• pp.64-68
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• 2014

For the safe handling of cyclohexanol, this study was investigated the explosion limits of cyclohexanol in the reference data. The flash points and auto-ignition temperatures (AITs) by ignition delay time were experimented. The lower flash points of cyclohexanol by using closed-cup tester were experimented in$60^{\circ}C{\sim}64^{\circ}C$. The lower flash points of cyclohexanol by using open cup tester were experimented in $66^{\circ}C{\sim}68^{\circ}C$. This study measured relationship between the AITs and the ignition delay times by using ASTM E659 tester for cyclohexanol. The AIT of cyclohexanol was experimented as $297^{\circ}C$. The lower explosion limit (LEL) and the upper explosion limit UEL) by the measured the lower flash point and the upper flash point of cyclohexanol were calculated as 0.95 Vol% and 10.7 Vol%, respectively.