• Fire Science and Engineering
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• v.27 no.3
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• pp.47-51
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• 2013

The explosion limit is one of the major combustion properties used to determine the fire and explosion hazards of the flammable substances. The explosion limit of organic acids have been shown to be correlated the heat of combustion and the chemical stoichiometric coefficients. In this study, the lower explosion and upper explosion limits of organic acids were predicted by using the heat of combustion and chemical 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 organic acids.

• Journal of the Korean Institute of Gas
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• v.10 no.1 s.30
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• pp.19-25
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• 2006

Explosion limit is one of the major physical properties used to determine the fire and explosion hazards of the flammable substances. Explosion limits are used to classify flammable materials according to their relative flammability. Such a classification is important for the safe handling, storage, transportation of flammable substances. In this study, the lower explosion limits(LEL) of the flammable mixtures predicted with the appropriate use of the vapor composition and the heat of combustion of the individual components which constitute mixture. The values calculated by the proposed equations were a good agreement with literature data within a few percent. From a given results, It is to be hoped that this methodology will contribute to the estimation of the explosive properties of flammable mixtures with improved accuracy and the broader application for other flammable substances.

• Fire Science and Engineering
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• v.25 no.2
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• pp.114-119
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• 2011

Explosion limit and flash point are the major combustion properties used to determine the fire and explosion hazards of the flammable substances. In this study, in order to predict upper explosion limits (UEL) for acids and ketones, the upper flash point of these were measured under the VLE (vaporliquid equilibrium) state by using Setaflash closed cup tester (ASTM D3278). The UELs calculated by Antoine equation by using the experimental upper flash point are usually lower than the several reported UELs. From the given results, using the proposed experimental and predicted method, it is possible to research the upper explosion limits of the other flammable substances.

• 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.

• Korean Chemical Engineering Research
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• v.56 no.6
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• pp.811-818
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• 2018

A fire and explosion accident caused by a liquefied petroleum gas (LPG) welding and cutting torch gas leak occurred 10 m underground at the site of reinforcement work for bridge columns, killing four people and seriously injuring ten. We conducted a comprehensive investigation into the accident to identify the fundamental causes of the explosion by analyzing the structure of the construction site and the properties of propane, which was the main component of LPG welding and cutting work used at the site. The range between the lower and upper explosion limits of leaking LPG for welding and cutting work was examined using Le Chatelier's formula; the behavior of LPG concentration change, which included dispersion and concentration change, was analyzed using the fire dynamic simulator (FDS). We concluded that the primary cause of the accident was combustible LPG that leaked from a welding and cutting torch and formed a explosion range between the lower and upper limits. When the LPG contacted the flame of the welding and cutting torch, LPG explosion occurred. The LPG explosion power calculation was verified by the blast effect computation program developed by the Department of Defense Explosive Safety Board (DDESB). According to the fire simulation results, we concluded that the welding and cutting torch LPG leak caused the gas explosion. This study is useful for safety management to prevent accidents caused by LPG welding and cutting work at construction sites.

• Journal of the Korean Society of Safety
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• v.29 no.3
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• pp.39-45
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• 2014

For the safe handling of n-hexadecane, the lower flash points and the upper flash point, fire point, AITs(auto-ignition temperatures) by ignition delay time were experimented. Also lower and upper explosion limits by using measured the lower and upper flash points for n-hexadecane were calculated. The lower flash points of n-hexadecane by using the Setaflash and the Pensky-Martens closed testers were measured $128^{\circ}C$ and $126^{\circ}C$, respectively. The lower flash points of the Tag and the Cleveland open cup testers were measured $136^{\circ}C$ and $132^{\circ}C$, respectively. The fire points of the Tag and the Cleveland open cup testers were measured $144^{\circ}C$. respectively. This study measured relationship between the AITs and the ignition delay times by using ASTM E659 apparatus for n-hexadecane. The experimental AIT of n-hexadecane was $200^{\circ}C$. The calculated lower and upper explosion limit by using measured lower $128^{\circ}C$ and upper flash point $180^{\circ}C$ for n-hexadecane were 0.42 Vol.% and 4.70 Vol.%.

• Journal of the Korean Society of Safety
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• v.28 no.4
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• pp.53-57
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• 2013

For the safe handling of n-pentadecane, the lower flash points and the upper flash point, fire point, AITs(auto-ignition temperatures) by ignition delay time were experimented. Also lower and upper explosion limits by using measured the lower and upper flash points for n-pentadecane were calculated. The lower flash points of n-pentadecane by using closed-cup tester were measured $118^{\circ}C$ and $122^{\circ}C$. The lower flash points and fire point of n-pentadecane by using open cup tester were measured $126^{\circ}C$ and $127^{\circ}C$, respectively. This study measured relationship between the AITs and the ignition delay times by using ASTM E659 apparatus for n-pentadecane. The experimental AIT of n-pentadecane was $195^{\circ}C$. The calculated lower and upper explosion limit by using measured lower $118^{\circ}C$ and upper flash point $174^{\circ}C$ for n-pentadecane were 0.54 Vol.% and 6.40 Vol.%.

• Fire Science and Engineering
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• v.12 no.4
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• pp.13-19
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• 1998

We investigated the weight loss according to temperature using Thermal Gravimetric Analysis(TGA) in order to find the thermal hazard of carbon black(Hi-Black 10, Hi-Black 50L) dusts, and the properties of dust explosion in variation of the surface functional groups and specific surface area of their dust with the same particle size. Using Hartman's dust explosion apparatus which estimate dust explosion by electric ignition after making dust disperse by compressed air, dust explosion experiments have been conducted by varying concentration and size of carbon black dust. The explosion pressure of both carbon black increased as the specific surface area increased. The results indicated that Hi-Block 50L of which specific surface area was larger three to four times than that of Hi-Black 10 was much easier of dust explosion.

• Fire Science and Engineering
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• v.12 no.3
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• pp.3-9
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• 1998

We investigated the weight loss according to temperature using TGA in order to find the thermal hazard of brand-new activated-carbon and disused activated-carbon dusts, and the properties of dust explosion in variation of the specific surface area of their dust with the same particle size. Using hartman's dust explosion apparatus which estimate dust explosion by electric ignition after making dust disperse by compressed air, dust explosion experiments have been conducted by varying concentration and size of activated carbon dust. The explosion pressure of both activated carbon increased as the specipic surface area increased. The results indicated that brand-new activated-carbon of which specific surface area was larger three to four times than that of disused activated-carbon was much easier of dust explosion.

• Fire Science and Engineering
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• v.22 no.3
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• pp.228-233
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• 2008

Detonation limit is one of the major physical properties used to determine the fire and explosion hazards of the flammable substances. In this study, the lower detonation limits (LDL) and the upper detonation limits (UDL) of the flammable substances predicted with the appropriate use of the heat of combustion and the stoichiometric coefficient. The values calculated by the proposed equations were a good agreement with literature data within a few percent. From a given results, It is to be hoped that this methodology will contribute to the estimation of the detonation limits of for other flammable substances.