• Title/Summary/Keyword: Flame Time

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A study on the efficiency advancement for evacuation of the crews by ship structural improvement (선박 구조 개선을 통한 승무원의 피난 효율 향상을 위한 연구)

  • Kim, Wonouk;Lee, Myoungho;Kim, Jongsu
    • Journal of Advanced Marine Engineering and Technology
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    • v.38 no.3
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    • pp.342-348
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    • 2014
  • Onshore great fires can normally be extinguished by firefighters using special firefighting equipment and its suitable method. However, offshore fires on the ships are to be extinguished by the crew without any supports from the onshore. Also, crews working on board are exposed to high risk of emergency evacuation due to the complicated structure arrangement of the ships and different accident types such as fire and ship collisions. As most of damage and loss of life in fire are associated with suffocation, shortening of evacuation time is an important factor to improve a survival rate. In this study, visibility in the accommodation area is analyzed by using the temperature and smoke flow which are obtained by the Fire Dynamic Simulator(FDS) as a Three-Dimensional Fire Analysis program to understand the survival rate of the crew upon the fire. The fire doors for most of ships are designed to close automatically when the fire alarm is activated. These automatic closing of the fire doors is a very effective system to delay the spread of flame and smoke flow for the unmanned spaces of the fire protected area. However, if the crew cannot escape within the estimated time, the crew inside the fire protected area will be damaged a lot. In this paper, the comparative analysis between the evacuations by using the fire door from the fire protected area and the suggested fire shielding structure in this study is carried out by the smoke flow rate and the temperature rise rate.

A study on the Application of Optimal Evacuation Route through Evacuation Simulation System in Case of Fire (화재발생 시 대피시뮬레이션 시스템을 통한 최적대피경로 적용에 관한 연구)

  • Kim, Daeill;Jeong, Juahn;Park, Sungchan;Go, Jooyeon;Yeom, Chunho
    • Journal of the Society of Disaster Information
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    • v.16 no.1
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    • pp.96-110
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    • 2020
  • Recently, due to global warming, it is easily exposed to various disasters such as fire, flood, and earthquake. In particular, large-scale disasters have continuously been occurring in crowded areas such as traditional markets, facilities for the elderly and children, and public facilities where various people stay. Purpose: This study aims to detect a fire occurred in crowded facilities early in the event to analyze and provide an optimal evacuation route using big data and advanced technology. Method: The researchers propose a new algorithm through context-aware 3D object model technology and A* algorithm optimization and propose a scenario-based optimal evacuation route selection technique. Result: Using the HPA* E algorithm, the evacuation simulation in the event of a fire was reproduced as a 3D model and the optimal evacuation route and evacuation time were calculated for each scenario. Conclusion: It is expected to reduce fatalities and injuries through the evacuation induction technique that enables evacuation of the building in the shortest path by analyzing in real-time via fire detection sensors that detects the temperature, flame, and smoke.

Evaluation of Combustion Gas for Carbon Oxide of Wood Coated with Bis-(dialkylaminoalkyl) Phosphinic Acids Additives

  • Jin, Eui;Chung, Yeong-Jin
    • Fire Science and Engineering
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    • v.30 no.4
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    • pp.65-72
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    • 2016
  • This study examined the generation of combustion toxic gases of pinus rigida specimens processed with bis-(dimethylaminomethyl) phosphinic acid (DMDAP), bis-(diethylaminomethyl) phosphinic acid (DEDAP), and bis-(dibutylaminomethyl) phosphinic acid (DBDAP). Each pinus rigida plate was coated three times with 15 wt.% flame retardants in an aqueous solution. The specimens were then dried at room temperature. The production of combustion toxic gases was investigated using a cone calorimeter (ISO 5660-1). The first time to peak mass loss rate ($1^{st}-TMLR_{peak}$) processed with the chemical additives decreased to 5.9 from 41.2% compared with the unprocessed specimen. The second time to the peak mass loss rate ($2^{nd}-TMLR_{peak}$) for the processed specimens was decreased 1.8% for DMDAP and 5.3% for DBDAP and increased 1.8% for DEDAP. The peak carbon monoxide ($CO_{peak}$) production was 1.5 to 2.0 times higher than that of the unprocessed plate. The peak carbon dioxide ($CO_{2peak}$) production was reduced 0.01 times for DMDAP and increased 1.15 to 1.19 times for DEDAP and DBDAP compared with the unprocessed specimens. In particular, the oxygen concentration was much higher than 15%, which can be fatal to humans and the resulting hazard can be eliminated. Overall, the combustion toxicity of flammable gas were increased partially by the chemical additives compared with those of the unprocessed plate.

Experimental Study on the Effects of Combustion Products on the Human Body and Suggestion of Law Revision (흡음재의 연소 생성물이 인체에 미치는 영향에 대한 실험적 연구 및 법률 개정 제언)

  • Kang, Jung Ki;Choi, Don Mook
    • Fire Science and Engineering
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    • v.33 no.4
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    • pp.28-34
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    • 2019
  • Regardless of the ignition source, the main factors affecting the spread of flames to the human body are combustibles. The sound absorption material, which is the finishing material used in music institutes and karaoke rooms, consists of polyurethane that generates a large amount of toxic gas with a high amount of combustion gases during a fire. Still, the current law does not require the use of impregnated finishing materials for tutoring services with less than 100 users. In this study, the rate of flame diffusion was measured using the MultiRaelite composite gas measuring instrument (target substance VOC, HCHO, SO2, CO2, CO, HCN, and NO2) for the collection of sound-absorbing materials installed in the actual music academy. The results showed that the toxic gas found in this experiment exceeded the allowable concentration of TWA (Time Weighted Average) and STEL (Short Term Exposure Limit). In addition, a comparative combustion test of the general sound absorber and non-combustion sound absorbing materials on the market showed wide differences in ignition and diffusion. Therefore, based on the results of the experiment, private institutes with less than 100 users should be mandated to use non-combustion sound absorbing materials.

Simple Method in Trace Analysis of Phthalates in Cosmetics : Analytical Conditions and Skills for Better Results (화장품에서 프탈레이트 미량분석을 위한 간편한 분석법 : 향상된 결과를 위한 분석조건과 기술)

  • Kim, Min-Kee;Jung, Hye-Jin;Chang, Ih-Seop
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.34 no.1
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    • pp.51-55
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    • 2008
  • Although phthalates aren't used as an cosmetic ingredient, some cosmetics especially nail lacquer, hair spray, and perfume still have phthalates. This is mainly caused by contamination and carryover during manufacturing process, so analysis of phthalates in those cosmetics has became a very important thing for quality-assurance(Q.A). The main phthalates under debate are diethyl phthalate(DEP), dibutyl phthalate(DBP), and bis(2-ethylhexyl) phthalate (DEHP) in domestic market. Gas chromatography-mass spectrometry(GC-MS) coupled with solvent extraction and concentration has been used for ppm level and sub ppm level analysis of phthalates. It requires much time and cost to use mass spectrometric detector and to prepare the test solution. Moreover analysis of phthalates at low concentrations is difficult because of contamination which results in wrong analytical results. In the present study, we showed a simple method using gas chromatography-flame ionization detector(GC-FID) which has fast analysis time, minimum use of solvent, reduced sample preparation steps for minimizing contamination and quantitative range of $2{\sim}50{\mu}g/g(ppm)$ in products. Consequently, this method will be proper for Q.A analysis in related companies.

Combustive Properties of Medium Density Fibreboards (MDF) Treated with Bis-(Dimethylaminomethyl) Phosphinic Acid and Alkylenediaminoalkyl-Bis-Phosphonic Acids (비스-디메틸아미노메틸 포스핀산과 알킬렌디아미노알킬-비스-포스폰산 유도체에 의해 처리된 중밀도 섬유판의 연소특성)

  • Park, Myung-Ho;Chung, Yeong-Jin
    • Fire Science and Engineering
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    • v.28 no.5
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    • pp.71-79
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    • 2014
  • This study was performed to test the combustive properties of Medium Density Fibreboards (MDFs) treated with chemicals of the bis-(dimethylaminomethyl) phosphinic acid (DMDAP), N,N-dimethylethylenediaminomethyl-bis-phosphonic acid (DMDEDAP), piperazinomethyl-bis-phosphonic acid (PIPEABP), and methylpiperazinomethyl-bis-phosphonic acid (MPIPEABP). MDFs were painted in three times with 15 wt% solution of the bis-(dimethylaminomethyl) phosphinic acid and alkylenediaminoalkyl-bis-phosphonic acids at the room temperature, respectively. After drying MDF treated with chemicals, combustive properties and volatile organic compounds (VOCs) contents were examined by the cone calorimeter (ISO 5660-1), test for flame retardant (NEMA Notice No. 2012034), and gas chromatography (KS M ISO 11890-2), respectively. It was indicated that the MDFs treated with chemicals showed the longer time to combustion time (CT) = (442~492) s than that of virgin plate by reducing the burning rate except for CT treated with DMDAP. In adition, the MDFs treated with chemicals showed both of the higher char area (44.33~61.33) kg/kg and char length (10.33~11.67) cm than those of virgin plate. Especially, the MDFs treated with chemicals showed the higher mean volatile organic compounds (VOCs) (0.188~0.333) g/L than that of virgin plate within the prescribed limits. Thus, It is supposed that the combustion- retardation properties were improved by the partial due to the treated chemicals in the virgin MDF.

Treatment of Heterotopic Calcification with Ulceration in Burn Scar (화상 반흔에서 생긴 궤양을 동반한 이소성 석회화의 치료)

  • Kang, Sang-Gu;Lee, Jong-Wook;Ko, Jang-Hyu;Seo, Dong-Kook;Choi, Jai-Koo;Jang, Young-Chul
    • Archives of Plastic Surgery
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    • v.37 no.4
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    • pp.415-420
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    • 2010
  • Purpose: Heterotopic calcification is a pathological event in which deposits of calcium salts build up, usually in the joint area or soft tissues. It can occur under many conditions and in some rare cases may develop in burn scars. In particular, ulcerations in burn scars accompanied by heterotopic calcification are difficult to treat through conservative treatment. This study reports methods for accurate diagnosis and adequate treatment of ulceration in burn scars accompanied by heterotopic calcification. Methods: Fourteen patients who visited our hospital from March 2008 to January 2010 were subjected to this study. Their sex, age, modes of burn, degree, TBSA (%), ulcerated area, the time of occurrence of the ulcerations in the burn scars were investigated. In addition, radiological examination and biopsy was performed to diagnose heterotopic calcification. Results: Among the 14 cases, 6 were male and 8 were female. The average age of the patients was 48.2 (27 - 69 yrs). As for the mode of burn, 11 were flame burns and 3 were scalding burns. The average time of occurrence of the ulcerations in the burn scars was 4.5 months. The ulcerated areas were situated in the legs in 12 cases, arms in 1 case, and torso in 1 case. The diagnosis was confirmed through X-ray and biopsy, and skin graft was performed after wide excision. Conclusion: Diagnosis of the ulceration in burn scars accompanied by heterotopic calcification is possible through radiological and pathologic studies. Surgical treatment is the most reliable method of treatment, and we chose to perform skin graft after wide excision. Also, we learned that the complete removal of the calcified tissue and the inflammatory fibrotic tissues is crucial in preventing recurrence. Also, in contrast to Marjolin's ulcer, heterotopic calcification had a small size, little or no granulation tissue, and lacked fungating type ulceration. Therefore, favorable prognosis could be achieved through adequate treatment.

A Study on the Evacuation Risk of Simultaneous Fires from Exterior (외장재에 의한 동시다발적인 화재의 피난위험성에 관한 연구)

  • Min, Se-Hong
    • Fire Science and Engineering
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    • v.26 no.4
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    • pp.48-54
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    • 2012
  • In order to study on the evacuation risk when connate fires caused by vertical fire spread of the exterior occurs, the egress simulations based on the relevant scenarios has carried out. As a result of it, ASET (permitted evacuation time) was reached in between 550 to 650 seconds in entire floors after vertical smoke spread from fire of combustible exteriors. In particular, ASET was 358 seconds in the first floor, 490 seconds in the six floor and 473 seconds in the tenth floor. In addition, five floors of all levels, the 1st floor, the 6th floor and the 28th floor ~30th floor, show RSET (minimum evacuation time) which is bigger than ASET as evacuation risk. This result presents occupants in high rise buildings with more than 15 floors might not be able to egress of them using staircases due to huge population attempting to evacuate simultaneously. Particularly, 699 people in the upper levels by smoke from the first floor are having difficulty escaping this building since ASET on the first floor adjacent to the ignition point was 358 seconds which is relatively reached fast. Considering a prevention method of the fire and smoke spread, architects have to use non-combustible exterior in the building's facade to be required as an active fire protection system.

An Experimental Study on the Influence of the Spread of Firebrand on Building Exterior Materials and Roofing Materials in Urban Areas (도심지 인접 산불의 불티 확산이 건축물 외장재와 지붕재에 미치는 영향에 관한 실험적 연구)

  • Min, Jeong-Ki
    • Journal of the Society of Disaster Information
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    • v.17 no.3
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    • pp.617-626
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    • 2021
  • Purpose: The purpose of this study is to evaluate the fire srpead risk of building exterior and roofing materials due to the firebrand of forest fire occurring in the urban areas. Method: In order to achieve this research purpose, by selecting building materials used for exterior and roofing materials of buildings, the time to ignition, total heat release, and heat release rate were investigated, and a forest fire firebrand system was established to the possibility of fire spread was confirmed. Result: As a result of the cone calorimeter test, the roofing material had a similar or faster ignition time due to radiant heat compared to the exterior material with the steel plate exposed to the outside, and showed a higher heat release rate and total heat release than the exterior material. Although it was affected by the flammable material, it was confirmed that it did not spread easily due to the limited amount of combustible material, and carbonization marks appeared inside. Conclusion: The cone calorimeter test method has been shown to be useful in understanding the combustion characteristics of building materials by radiant heat, but the fire spread due to a firebrand in a forest fire is directly affected by the flame due to the ignition of surrounding combustibles, so finding a direct correlation with the cone calorimeter method is difficult. It is judged that the roof material may be more vulnerable to the spread of fire due to the fire than the exterior material.

Heat Risk Assessment of Wood Coated with Silicone Compounds (실리콘 화합물로 도포된 목재의 열위험성 평가)

  • Jin, Eui;Chung, Yeong-Jin
    • Fire Science and Engineering
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    • v.33 no.2
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    • pp.9-19
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    • 2019
  • Experiments on the combustion characteristics of untreated wood specimens and those treated with four types of silicone compounds were carried out using a cone calorimeter according to the ISO 5660-1 standard. 3-Aminopropyltrimethoxysilane (APTMS), 3-(2-aminoethylamino) propylmethyldimethoxysilane (AEAPMDMS), and 3-(2-aminoethylamino) propyltrimethoxysilane (AEAPTMS) were used as the silane compounds. The flame retardants were synthesized with sodium silicate and amino silane compounds. The measured time to ignition after combustion at an external heat flux of $50kW/m^2$ was 9 s to 11 s. Time to ignition was marked with a delayed value in the 3 s to 5 s range. The peak heat release rate ($HRR_{peak}$) was reduced by 5 to 20% compared with the uncoated specimen, and AEAPMDMS showed the highest initial fire risk. The total heat release (THR) was decreased by 1 to 22%. Compared to the untreated specimen, the fire performance index (FPI) of the specimens coated with silicone sol compounds increased by 1.5 to 2.2 fold. The fire growth index (FGI) of the AEAPMDMS specimen was increased by 30% and the others were decreased by 93 to 94%. Therefore, the fire risk of wood coated with silicone compounds was improved in terms of the heat risk properties.