• Title/Summary/Keyword: Flammable materials

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Study on the Limiting Oxygen Index of Curtain Exposed to High Temperature (고온에 노출된 커튼의 한계산소지수에 관한 연구)

  • Kim, Hwang-Jin
    • Fire Science and Engineering
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    • v.32 no.5
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    • pp.1-5
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    • 2018
  • Curtains are used for shading in windows. Since most curtains are made of flammable materials and are installed vertically, curtains can be an important factor in fire spreading. Accordingly, it is important to predict fire behaviors in studies on the combustion characteristics of flammable interior decorations, such as curtains. In this study, to analyze the combustion characteristics of six kinds of curtains, which are widely used interior decorations, the oxygen index was measured at room temperature and higher temperature. As a result of the experiment, the oxygen index at higher temperature of all specimens was about 3%~7.5% lower than that at room temperature and difference of 0.2% of oxygen index show big differences in combustion phenomenon of specimens. Therefore, when flame retardancy is evaluated with the oxygen index value of flammable interior decorations, the oxygen index value at higher temperature should be sufficiently considered.

Sensitivity Characteristics on the Composition Change of the Gas Sensing Materials based on $In_2O_3$ Semiconductor. ($In_2O_3$계 반도성 가스감지재료의 조성변화에 따른 감도특성)

  • 정형진;유광수
    • Journal of the Korean Ceramic Society
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    • v.22 no.4
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    • pp.54-60
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    • 1985
  • Gas sensing materials for detecting flammable gases such as $CH_4$, $C_3H_8$ and n-$C_4H_{10}$ were developed by util-izing $In_2O_3$ as the principal sensing material. The sensing materials were formulated by mixing $In_2O_3$ powder with one or two other chemicals such as $SnO_2$, $Y_2O_3$ and $Al_2O_3$ with a small addition of $PdCl_2$ as a catalyst. Sample of sensor were fabricated by coating each of the mixtures on a ceramic tube impregnating ethylsili-cate and firing at 75$0^{\circ}C$ Each material mixture was evaluated by measuring and comparing gas sensitivity(resistance in air/resistance with gas) to flammable gases such as $CH_4$, $C_3H-8$ and n-$C_4H_{10}$. It was found that among fifteen compositions tested three compositions as follows show the highest gas sensitivity and thus are very feasible for commercialization as the gas sensors ; o49.5 $In_2O_3$+50 Al2O3_0.5 PdCl2(wt%) o $20In_2O_3+29$ $SnO_2+50$ $Al_2O_3+1$ $PdCl_2$(wt%) o40 $In_2O_3$+9 $Y_2O_3+50$ $Al_2O_3+1$ $PdCl_2$(wt%)

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A Study on the Assessment of Hazardous Properties of the Chemicals (화학물질의 위험성평가에 관한 연구)

  • Lee, Bong-Woo;Park, Chul-Woo;Song, Haak;Choi, Jeong-Soo
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2008.11a
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    • pp.262-269
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    • 2008
  • Chemical products have had an favorable influence on our everyday life, and contributed very much to the development of human culture. According to the rapid change of industry and the development of scientific technique the using chemical products are increasing more and more. Chemical products can have any hazardous property such as flammability or explosiveness. There are occurring many accidents in the international trade due to the different classification and labelling of chemicals produced in various countries. The main purpose of this work is the development of global standard test methods for the chemicals, and the classification and labelling in building block approach by means of the basic technical data. Oxidizing solids, combustible solids, spontaneously combustible materials, water-prohibitive materials, flammable liquids, self-reactive materials and oxidizing liquids have been tested. The results have been classified according to the hazard material safety regulation and the UN regulation, and summarized in a data-base.

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Manufacturing Polymer/clay Nanocomposites Using a Supercritical Fluid Process

  • Jung, Hyun-Taek;Yoon, Ho-Gyu;Lim, Soon-Ho
    • International Journal of Precision Engineering and Manufacturing
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    • v.9 no.4
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    • pp.63-65
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    • 2008
  • The increased interest in reducing the environmental effects caused by releasing organic compounds and aqueous waste has motivated the development of polymeric materials in supercritical fluids. Recently, supercritical fluids have been used in material synthesis and processing because of their special properties, such as high diffusivity, low viscosity, and low surface tension. Supercritical carbon dioxide is the most attractive because it is non-toxic, non-flammable, and has moderate critical temperature and critical pressure values. Supercritical carbon dioxide can also swell most polymers. In this study, we prepared polymer/clay nanocomposites using supercritical fluids. Cloisites 10A, 15A, 25A, and 30B used in this study are montmorillonites modified with a quaternary ammonium salt. The nanocomposites of polymer/clay were characterized by X-ray diffraction, thermogravimetric analysis, and differential scanning calorimetry.

Development and Performance Evaluation of Non-flammable Mineral Foam Board Using Waste Glass (폐유리를 활용한 불연 무기물 발포 보드 개발 및 성능평가)

  • Kim, Hyen-Soo;Choi, Won-Young;Kim, Sang-Heon;Choi, Seung-Hwan;Park, Soon-Don
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.8 no.1
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    • pp.17-25
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    • 2020
  • In this study, non-flammable mineral foam board using waste glass that can be produced to standardized specifications were developed and evaluated for the performance. In addition to the physical and mechanical performance, the environmental properties such as insulation, non-combustibility, gas hazard, sound absorption, etc. were tested to verify the use as interior and exterior building materials. Through the structural review, the validity was verified for the application of the office and restaurant building.

A Study on the Ignition Hazard of Flammable Mixtures by Radio-Frequency Spark (고주파 스파크에 의한 가연성 혼합가스의 점화위험성에 관한 연구)

  • Choi, Sang-Won;Lee, Gwan-Hyung;Moon, Jung-Gi
    • Proceedings of the KIEE Conference
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    • 1996.07c
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    • pp.1913-1916
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    • 1996
  • With a progress of electrical and electronic technology, radio-frequency circuits including high frequency components are widely applied to various industrial installations. Some of them are used in hazardous locations where explosive or flammable gases exist. As a result, ignition of such gases may be induced by a spark discharge when the radio frequency circuits are switched on or off. The purpose of this study is to investigate the ignition hazards of acetylene-air and ethylen-air mixtures experimentally based on the IEC 79-3 publication. In this experiment, we used a high frequency resistive circuit which consists of a co-axial cable, a $10{\Omega}$, $20{\Omega}$, $30{\Omega}$, $40{\Omega}$ or $50{\Omega}$ resistor and a power amplifier with frequency range up to almost 1 MHz. Experimental results show that the ignition of the acetylene-air and ethylen-air mixtures due to spark discharge depends primarily on the frequency of the power source in the resistive circuit: the minimum ignition voltage increases gradually with the increase of the frequency.

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Proposal for Ignition Source and Flammable Material Safety Management through 3D Modeling of Hazardous Area: Focus on Indoor Mixing Processes (폭발위험장소 구분도의 3D Modeling을 통한 점화원 및 가연물 안전관리 방안 제안: 실내 혼합공정을 중심으로)

  • Hak-Jae Kim;Duk-Han Kim;Young-Woo Chon
    • Journal of the Society of Disaster Information
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    • v.20 no.1
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    • pp.47-59
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    • 2024
  • Purpose: This study aims to propose measures for the prevention of fire and explosion accidents within manufacturing facilities by improving the existing classification criteria for hazardous locations based on the leakage patterns of flammable liquids. The objective is to suggest ways to safely manage ignition sources and combustible materials. Method: The hazardous locations were calculated using "KS C IEC 60079-10-1," and the calculated explosion hazard distances were visualized in 3D. Additionally, the formula for the atmospheric dispersion of flammable vapors, as outlined in "P-91-2023," was utilized to calculate the dispersion rates within the hazardous locations represented in 3D. Result: Visualization of hazardous locations in 3D enabled the identification of blind spots in the floor plan, facilitating immediate recognition of ignition sources within these areas. Furthermore, when calculating the time taken for the Lower Explosive Limit (LEL) to reach within the volumetric space of the hazardous locations represented in 3D, it was found that the risk level did not correspond identically with the explosion hazard distances. Conclusion: Considering the atmospheric dispersion of flammable liquids, it was concluded that safety management should be conducted. Therefore, a method for calculating the concentration values requiring detection and alert based on realistically achievable ventilation rates within the facility is proposed.

Fabrication and Characterization of Hexagonal Tungsten Oxide Nanopowders for High Performance Gas Sensing Application (육방정계 텅스텐옥사이드 나노분말의 합성과 고성능 가스센서응용을 위한 성능 평가)

  • Park, Jinsoo
    • Journal of Powder Materials
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    • v.26 no.1
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    • pp.28-33
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    • 2019
  • The gas sensor is essential to monitoring dangerous gases in our environment. Metal oxide (MO) gas sensors are primarily utilized for flammable, toxic and organic gases and $O_3$ because of their high sensitivity, high response and high stability. Tungsten oxides ($WO_3$) have versatile applications, particularly for gas sensor applications because of the wide bandgap and stability of $WO_3$. Nanosize $WO_3$ are synthesized using the hydrothermal method. As-prepared $WO_3$ nanopowders are in the form of nanorods and nanorulers. The crystal structure is hexagonal tungsten bronze ($MxWO_3$, x =< 0.33), characterized as a tunnel structure that accommodates alkali ions and the phase stabilizer. A gas detection test reveals that $WO_3$ can detect acetone, butanol, ethanol, and gasoline. This is the first study to report this capability of $WO_3$.

Development of Non-flammable exterior design Molding using Cellular Light-weight Concrete (CLC를 활용한 공동주택 불연성능 외벽몰딩 개발)

  • Kwon, Hae-Won;Gong, Min-Ho;Lee, Chang-Yong;Jeong, Gab-Cheol
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2020.06a
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    • pp.54-55
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    • 2020
  • Recently, "The rules on the standards of evacuation and fire protection of buildings" require that non-burnable materials such as non-combustible and semi-non-combustible materials be used as the materials applied to the building's exterior walls, but styrofoam, which is a combustible material, has been applied a lot and became a social issue. In this study, we developed a non-combustible outer wall molding to secure construction and economic feasibility and free expression using CLC(CLC: Cellular Light-weight Concrete).

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Offsite Risk Assessment on Flammable Hazard Site (가연성물질 저장설비의 사고시 사업장외에 미치는 영향평가)

  • Lee, Dong Hoon;Park, Kyo Shik;Kim, Tae Ok;Shin, Dong Min;Shin, Seo Yun
    • Korean Journal of Hazardous Materials
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    • v.3 no.1
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    • pp.52-58
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    • 2015
  • Since the HF release in 2012 in Korea, it became one of the most significant to evaluate consequence to the vicinity of industry facilities handling hazardous materials. BTX plant is selected to assess off-site risk to check whether the facility satisfies the Chemical Control Law by Korea Government. Accident scenarios were listed using process safety information. The scenarios having effect to the off-site were selected and assessed further according to guideline provided by Korea government. Worst case and alternative scenarios including other interested scenarios were evaluated using ALOHA. Each evaluated scenario was assessed further considering countermeasures. The results showed that the facility handling chloric acid is safe enough and needed no further protections at the moment.