• Title/Summary/Keyword: Smoke lay

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Distribution of Heat and Smoke Related to Openings in Hise-Rise Apartment Building Fires (고층 공동주택의 개구특성에 따른 화재시 열.연기유동에 관한 연구)

  • 이지희
    • Fire Science and Engineering
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    • v.15 no.2
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    • pp.59-79
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    • 2001
  • The paper proposes alternatives for fire safety in architectural planning through heat-smoke distribution related to openings so that we decrease casualty and property loss by fire and lay a great emphasis on building high-rise apartments with consideration of fire safety in Korea. An analysis program(HFA-Heat Fluid Analysis) is built to perform simultaneously numerical analysis and experimental analysis on rooms, units and buildings. In consequence, on the first, fire prevention methods are required to be set up related to openings for design rooms since the flow of heat and smoke is influenced by the type of openings in high-rise apartments. Second, the numerical analysis showed that different planning types cause to show differences in the spreading time of heat and smoke to design the units of high-rise apartments. On the third, each unit building showed different fire behavior depending on openings by numerical analysis and small scaled experiment on heat and smoke flow.

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Prevalence and Factors Associated with Smoking Intentions among Non-smoking and Smoking Adolescents in Kota Tinggi, Johor, Malaysia

  • Hock, Lim Kuang;Ghazali, Sumarni Mohamad;Cheong, Kee Chee;Kuay, Lim Kuang;Li, Lim Hui;Huey, Teh Chien;Ying, Chan Ying;Yen, Yeo Lay;Ching, Fiona Goh Swee;Yi, Khoo Yi;Lin, Chong Zhuo;Ibrahim, Normala;Mustafa, Amal Nasir
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.10
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    • pp.4359-4366
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    • 2014
  • Intention to smoke is a valid and reliable factor for predicting future smoking habits among adolescents. This factor, however, has received inadequate attention in Malaysia. The present paper elaborates the prevalence and factors associated with intent to initiate or to cease smoking, among adolescent nonsmokers and smokers in Kota Tinggi, Johor, Malaysia. A total of 2,300 secondary school students aged 13-16 years were selected through a two-stage stratified sampling method. A set of standardized questionnaires was used to assess the smoking behavior among adolescents and the inter-personal and intra-personal factors associated with smoking intention (intention to initiate smoking or to cease smoking). Multivariable logistic regression was used to identify factors related to smoking intention. The prevalence of intention to smoke in the future or to cease smoking among non-smoking adolescents and current smokers were 10.7% and 61.7% respectively. Having friends who smoke, social influence, and poor knowledge about the ill effects on health due to smoking showed significant relationships with intention to smoke in the future among non-smokers. Conversely, perceived lower prevalence of smoking among peers, weak contributory social influence, and greater awareness of the ill effects of smoking are factors associated with the intention to cease smoking sometime in the future. The study found that prevalence of intention to initiate smoking is low among non-smokers while the majority of current smokers intended to cease smoking in the future. Existing anti-smoking programmes that integrate the factors that have been identified in the current study should be put in motion to reduce the prevalence of intention to initiate smoking and increase the intention to cease smoking among adolescents.

Experimental Study of Fire Characteristics by Isocyanate Functional Parameter (이소시아네이트 관능기 매개인자에 의한 화재 특성의 실험적 연구)

  • Lee, Jae-Geol;Han, Kyoung-Ho;Jo, Hyung-Won;Yoon, Do-Young
    • Journal of the Korean Institute of Gas
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    • v.26 no.3
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    • pp.27-37
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    • 2022
  • With the recent increase in the spread of ESS (Electric Storage System), the damage to human life and property is also rapidly increasing due to continuous fires caused by ESS. In the manufacture of urethane sandwich panels used in ESS, it is necessary to improve the flame retardant performance. In this study, in order to realize the flame retardant properties of flexible polyurethane foam, the effect of the tissue density of the product due to the change of the isocyanate functional group parameter that changes the physical properties of the product on the fire performance was studied. The product was manufactured by changing the density of the urethane structure, and combustion performance tests, gas toxicity tests, and smoke density tests were performed. As a result, it was confirmed that the total amount of heat released had excellent performance when the isocyanate functional group was high, and had no correlation with the maximum heat release rate. When the value of the isocyanate functional group was 2.7 or more, the collapse of the shape could be prevented. In the gas hazard test, the performance was increased when the isocyanate functional group was relatively high, so a flame retardant for the Char system, which had a dense structure and easy to form a carbonized film, was added. confirmed to be. Therefore, as a result of this study, it is thought that it will be possible to lay the foundation for the development of a flame retardant to replace the cheap urethane sandwich panel used in the past.

Flame Retardant Properties of Basalt Fiber Reinforced Epoxy Composite with Inorganic Fillers (무기 필러가 첨가된 현무암섬유 강화 에폭시 복합재료의 난연 특성)

  • Mun, So Youn;Lee, Su Yeon;Lim, Hyung Mi
    • Composites Research
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    • v.32 no.6
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    • pp.368-374
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    • 2019
  • Basalt fiber reinforced epoxy composites with inorganic filler (BFRP-F) such as Mg(OH)2 (magnesium hydroxide), Al(OH)3 (aluminum hydroxide), Al2O3 (aluminum oxide) and AlOOH (boehmite) were prepared by hand lay-up and hot pressing. The combustive properties of BFRP-F were improved comparing with basalt fiber reinforced epoxy composite (BFRP) without inorganic filler. At a 30 wt% resin content, the limited oxygen index (LOI) of BFRP is 28.9, which is higher than that of epoxy (21.4), and the LOI of BFRP-F is higher than that of BFRP. The BFRP-F showed the lower peak heat release rate (PHRR), total heat release (THR) and total smoke release rate (TSR) than those of BFRP. We confirmed that the flame retardant properties of the composite were improved by the addition of inorganic filler through the dehydration reaction and oxide film formation.

Estimation of fire Experiment Prediction by Utility Tunnels Fire Experiment and Simulation (지하공동구 화재 실험 및 시뮬레이션에 의한 화재 설칠 예측 평가)

  • 윤명오;고재선;박형주;박성은
    • Fire Science and Engineering
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    • v.15 no.1
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    • pp.23-33
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    • 2001
  • The utility tunnels are the important facility as a mainstay of country because of the latest communication developments. However, the utilities tunnel is difficult to deal with in case of a fire accident. When a cable burns, the black smoke containing poisonous gas will be reduced. This black smoke goes into the tunnel, and makes it difficult to extinguish the fire. Therefore, when there was a fire in the utility tunnel, the central nerves of the country had been paralyzed, such as property damage, communication interruption, in addition to inconvenience for people. This paper is based on the fire occurred in the past, and reenacting the fire by making the real utilities tunnel model. The aim of this paper is the scientific analysis of the character image of the fire, and the verification of each fire protection system whether it works well after process of setting up a fire protection system in the utilities tunnel at a constant temperature. The fire experiment was equipped with the linear heat detector, the fire door, the connection water spray system and the ventilation system in the utilities tunnel. Fixed portion of an electric power supply cable was coated with a fire retardant coating, and a heating tube was covered with a fireproof. The result showed that the highest temperature was $932^{\circ}c$ and the linear heat detector was working at the constant temperature, and it pointed at the place of the fire on the receiving board, and Fixed portion of the electric power supply cable coated with the fire retardant coating did not work as the fireproof. The heating tube was covered with the fireproof about 30 minutes.

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Study on the Fire Risk Prediction Assessment due to Deterioration contact of combustible cables in Underground Common Utility Tunnels (지하공동구내 가연성케이블의 열화접촉으로 인한 화재위험성 예측평가)

  • Ko, Jaesun
    • Journal of the Society of Disaster Information
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    • v.11 no.1
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    • pp.135-147
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    • 2015
  • Recent underground common utility tunnels are underground facilities for jointly accommodating more than 2 kinds of air-conditioning and heating facilities, vacuum dust collector, information processing cables as well as electricity, telecommunications, waterworks, city gas, sewerage system required when citizens live their daily lives and facilities responsible for the central function of the country but it is difficult to cope with fire accidents quickly and hard to enter into common utility tunnels to extinguish a fire due to toxic gases and smoke generated when various cables are burnt. Thus, in the event of a fire, not only the nerve center of the country is paralyzed such as significant property damage and loss of communication etc. but citizen inconveniences are caused. Therefore, noticing that most fires break out by a short circuit due to electrical works and degradation contact due to combustible cables as the main causes of fires in domestic and foreign common utility tunnels fire cases that have occurred so far, the purpose of this paper is to scientifically analyze the behavior of a fire by producing the model of actual common utility tunnels and reproducing the fire. A fire experiment was conducted in a state that line type fixed temperature detector, fire door, connection deluge set and ventilation equipment are installed in underground common utility tunnels and transmission power distribution cables are coated with fire proof paints in a certain section and heating pipes are fire proof covered. As a result, in the case of Type II, the maximum temperature was measured as $932^{\circ}C$ and line type fixed temperature detector displayed the fire location exactly in the receiver at a constant temperature. And transmission power distribution cables painted with fire proof paints in a certain section, the case of Type III, were found not to be fire resistant and fire proof covered heating pipes to be fire resistant for about 30 minutes. Also, fire simulation was carried out by entering fire load during a real fire test and as a result, the maximum temperature is $943^{\circ}C$, almost identical with $932^{\circ}C$ during a real fire test. Therefore, it is considered that fire behaviour can be predicted by conducting fire simulation only with common utility tunnels fire load and result values of heat release rate, height of the smoke layer, concentration of O2, CO, CO2 etc. obtained by simulation are determined to be applied as the values during a real fire experiment. In the future, it is expected that more reliable information on domestic underground common utility tunnels fire accidents can be provided and it will contribute to construction and maintenance repair effectively and systematically by analyzing and accumulating experimental data on domestic underground common utility tunnels fire accidents built in this study and fire cases continuously every year and complementing laws and regulations and administration manuals etc.