• 한국안전학회지
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• 제31권4호
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• pp.42-47
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• 2016

The combustible properties(flash point, explosion limit and autoignition temperature) are the important safety items which are considered in the typical MSDS(material safety data sheet). In this study, for the safe handling of n-butyl methacrylate(n-BMA) being used in various ways in the chemical industry, the flash point and the autoignition temperature(AIT) of n-butyl methacrylate was experimented. And, the lower explosion limit of n-butyl methacrylate was calculated by using the lower flash point obtained in the experiment. The flash points of n-butyl methacrylate by using the Setaflash and Pensky-Martens closed-cup testers measured $44^{\circ}C$ and $51^{\circ}C$, respectively. The flash points of n-butyl methacrylate by using the Tag and Cleveland open cup testers are measured $53^{\circ}C$. The AIT of n-butyl methacrylate by ASTM 659E tester was measured as $295^{\circ}C$. The lower explosion limit by the measured flash point $44^{\circ}C$ was calculated as 0.85 vol.%. It was possible to predict lower explosion limit by using the experimental flash point or flash point in the literature.

• Korean Chemical Engineering Research
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• 제56권6호
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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.

• 한국안전학회지
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• 제22권5호
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• pp.65-70
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• 2007

This paper is estimation of structure damage caused by VCE(Vapor Cloud Explosion) in enclosure. As we estimate the influence of damage which occur at gas facility in factory. We can utilize the elementary data of safety distance. In this study, the influence of over-pressure caused by VCE in enclosure was calculated by using the Hopkinson's scaling law and the accident damage was estimated by applying the influence on the adjacent structure into the probit model. As a result of the damage estimation conducted by using the probit model, both the damage possibility of explosion overpressure to structures of 20 meters away and to glass bursting of 80 meters away was nearly zero in open space explosion.

• 한국안전학회지
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• 제31권5호
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• pp.42-48
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• 2016

The usage of the correct combustion properties of the treated substance for the safety of the process is critical. For the safe handling of n-nonane being used in various ways in the chemical industry, the flash point and the autoignition temperature(AIT) of n-nonane was experimented. And, the explosion limit of n-nonane was calculated by using the flash point obtained in the experiment. The flash points of n-nonane by using the Setaflash and Pensky-Martens closed-cup testers measured $31^{\circ}C$ and $34^{\circ}C$, respectively. The flash points of n-nonane by using the Tag and Cleveland open cup testers are measured $37^{\circ}C$ and $42^{\circ}C$. The AIT of n-nonane by ASTM 659E tester was measured as $210^{\circ}C$. The lower explosion limit by the measured flash point $31^{\circ}C$ was calculated as 0.87 vol%. And the upper explosion limit by the measured upper flash point $53^{\circ}C$ was calculated as 2.78 vol%. It was possible to predict lower explosion limit by using the experimental flash point or flash point in the literature.

• 한국안전학회지
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• 제32권5호
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• pp.25-31
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• 2017

The flash point, explosion limits, autoignition temperature(AIT) are important combustible properties which need special concern in the chemical safety process that handle hazardous substances. For the evaluation of the flammable properties of n-butylacetate, this study was investigated the explosion limits of n-butylacetate in the reference data. The flash points, fire points and AIT by the ignition delay time of n-butylacetate were experimented. The lower flash points of n-butylacetate by using the Setaflash and Pensky-Martens closed-cup testers were $24^{\circ}C$ and $26^{\circ}C$, respectively. The flash points of n-butylacetate using the Tag and Cleveland open cup testers are measured $31^{\circ}C$ and $40^{\circ}C$, respectively. And the fire points of n-butylacetate by the Tag and Cleveland open cup testers were measured $32^{\circ}C$ and $41^{\circ}C$. The AIT of n-butylacetate measured by the ASTM 659E tester was measured as $411^{\circ}C$. The lower explosion limit of lower flash point $24^{\circ}C$, which was measured by the Setaflash tester, was calculated to be 1.40 vol%. Also, the upper explosion limit of upper flash point $67^{\circ}C$ the Setaflash tester was calculated to be 12.5 vol%.

• 한국안전학회지
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• 제34권5호
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• pp.37-45
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• 2019

The characteristic of fire and explosion related to electrostatic discharge is that it is difficult to reproduce the electrostatic charge and discharge phenomenon in addition to the large human and material damage. Therefore, in order to prevent accidents and disasters related to electrostatic in fire and explosion hazard areas, it is important to manage the level of electrostatic in a safe manner from the perspective of system between industrial facilities and human bodies. Rule 325 of the Occupational Safety and Health Regulations, "Prevention of Fire / Explosion due to Electrostatic", requires the use of grounding, conductive materials, humidification and electrification in order to prevent the risk of disaster caused by static explosion and electrostatic in the production process. In order to comply with these measures, related technologies, standards and systems are needed from the viewpoint of preventive measures related to electrostatic in fire and explosion hazard areas, but in Korea, it is still insufficient. Therefore, technical, institutional and managerial measures are needed as a precautionary measure to improve the level of ESD safety in fire and explosion hazard areas and prevent electrostatic related injury. In Korea, we analyzed the current status and characteristics of electrostatic related disaster by using the statistics of industrial accident and fire statistics of the Ministry of Employment and Labor. We also analyzed the current status and characteristics of electrostatic related disasters in Japan using JNIOSH accidents and disasters investigation cases and JNIOSH fire accident data of Japan Fire Bureau. The purpose of this study is to compare and analyze the current status of electrostatic related accidents and disasters in Korea and Japan in order to improve the safety management of electrostatic in fire and explosion hazard areas. In order to prevent accidents and disasters in the industrial field, The technical, institutional, and managerial measures to manage the level of electrostatic in a safe state were derived from the system point of view.

• 전기학회논문지
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• 제67권3호
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• pp.474-478
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• 2018

The use of metals such as aluminum and titanium and the related industrial facilities have been continuously increasing to meet the requirements of the improvement of high-tech products due to the development of industry, and explosion of metal dust. Semiconductor process Metal dust is essential, but research is insufficient. The purpose of this study is to identify risk by analyzing the quantitative risk such as maximum explosion pressure and minimum explosion concentration applied international test standard in order to select the semiconductor process facilities handling dust and to predict possible risk of accidents.

• 대한안전경영과학회지
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• 제12권2호
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• pp.75-82
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• 2010

Gas turbines for power generating operate in a very high temperature condition and use natural gas for fuel. For this reason, many cases of damage happen at hot gas parts which are severely affected by high temperature gas and many cases of explosion occur by fuel gas. So a lot of efforts should be made to prevent hot gas parts damage and gas explosion accidents. Though there are many damage cases and explosion accidents, it is very difficult to find out the root causes of hot gas parts damage caused by gas explosion due to gas leakage in the heat exchanger for air cooling and gas heating. To prevent gas turbine from damage caused by gas explosion, removal of leakage gas from gas turbine is inevitably required before firing the gas turbine and installing alarm systems is also required for detecting gas leakage at stop valve to turbine while shut down.

• 한국안전학회지
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• 제17권4호
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• pp.126-132
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• 2002

By using the reference data, the empirical equations which describe the interrelationships of explosion properties and physical properties of n-chlorinated hydrocarbons have been derived. The properties which have been correlated are the lower and upper explosive limits, the stoichiometric coefficients, the heats of combustion, the carbon numbers. Also, the new equations using the mathematical and statistical methods for predicting the temperature dependence of lower explosive limits(LEL) of chlorinated hydrocarbons on the basis of the literature data are proposed. The fire and explosion properties calculated by the proposed equations in this research were a good agrement with literature data within a few A.A.P.E.(Average Absolute Percent Error) and A.A.D.(Average Absolute Deviation.) From a given explosive properties, by using the proposed equations, it is possible to predict to the fire and explosion characteristics for the other chlorinated hydrocarbons.

• 한국안전학회지
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• 제29권5호
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• pp.60-66
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• 2014

Depending on the progress of the industrial advances, the use of the thermal oil system in the utility system has been increased, which became an important part in the operation of the plant. However, fire or explosion have occurred due to lack of risk awareness and safety management, more frequently than we know. In this study, by using a questionnaire, actual conditions of safety management in thermal oil system is surveyed and analyzed, it is composed of general, a safety status of the thermal oil system component and the stage of recognition and management in the thermal oil system. These results of this study can be used as basic data to the safety management and the accident prevention of fire or explosion in the workplace.