• 한국화재소방학회논문지
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• 제29권4호
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• pp.81-88
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• 2015

본 연구에서는 다양한 화재실험에서 광학 연기밀도 측정을 위하여 광소멸법을 이용한 저가형 장치가 개발되었다. 저가형 장치의 상대적 측정 정확도는 He-Ne 레이저, 포토디텍터 및 다양한 광학부품을 이용한 고가의 표준장치에 의해 측정된 연기밀도의 비교를 통해 평가되었다. 저가형 장치는 레이저 모듈, 포토셀 그리고 아크릴 보드로 구성되었다. 연기농도의 조절이 용이한 연기 발생장치 실험을 통해, 저가형 장치는 표준장치에 비해 ${\pm}10%$의 범위 내에서 연기밀도를 측정할 수 있음을 확인하였다. 저가 장치의 신뢰성은 또한 폴리에틸렌 화염을 이용한 실험에서도 확인되었다. 결론적으로 개발된 저가형 장치는 연기밀도 측정을 위한 간편한 설치 및 실시간 측정과 함께 고가의 표준장치를 대신하여 사용될 것으로 기대된다.

• 한국안전학회지
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• 제21권5호
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• pp.6-11
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• 2006

This study aims to measure a smoke density and velocity by using the PIV method in case a fire occurs in tunnels. By doing so, this will estimate a critical velocity, examine its appropriateness, and present the basic materials necessary for designing a smoke control equipment. For this study, a visualization test was conducted based on the 1/20 miniature of a real tunnel according to the Froude scaling. As a part of basic experiments, a correlation between smoke density and brightness was analyzed here, and a critical velocity was estimated on the condition that a fire breaks out in tunnels. As a result, this study finds that there is a correlation between smoke density and brightness within a range of 100% to 30% transmittance, from which a quantitative smoke density can be obtained. The study also suggests that a critical velocity calculated from the Kennedy formula shows about 10% difference from that estimated in the test.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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• pp.251-254
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• 2001

In this paper, we analyzed the properties change of electric wire when the thermal stress was applied to NFR-8 and FR-PVC 600[V] wire. Messurement is made of the attenuation of a light beam by smoke accumulating with in a closed chamber due to nonflaming pyrolytic decomposition and flaming combustion. Results are expressed in terms of specific optical density which is derived from a geometrical factor and the measured optical density a measurement characteristic of the concentration of smoke. Referenced documents were ASTM E662 standard test method for specific Ds genalated by solid materials. The furnace control system shall maintain the required irradiance level under steady-state condition with the chamber door closed of $2.5{\pm}0.04[w/cm^{2}]$ for 20 min. According to the results of the smoke density analysis of NFR-8 and FR-PVC the highest decomposition flaming smoke density range of NFR-8 and FR-PVC were 25.2 to 37.5 and 51.1 respectively. Nonflaming smoke density range of NFR-8 and FR-PVC were 100.4 to 112.2 and 126.5 to 398.8. The amount of carbon monoxide generated was found to be much higher in FR-PVC decomposition than in NFR-8 due to incomplete combustion of FR-PVC which has high content of carbon in compound.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.251-254
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• 2001

In this paper, we analysed the properties change of electric wire when the thermal stress was applied to NFR-8 and FR-PVC [600] wire. Measurement is made of the attenuation of a light beam by smoke accumulating with in a closed chamber due to nonflamining pyrolytic decomposition and flaming combustion. Results are expressed in terms of specific optical density which is derived from a geometrical factor and the measured optical density a measurement characteristic of the concentration of smoke. Referenced documents were ASTM E662 standard test method for specific Ds generated by solid materials. The furnace control system shall maintain the required irradiance level under steady-state condition with the chamber door closed of 2.5${\pm}$0.04[w/$\textrm{cm}^2$] for 20 min. According to the results of the smoke density analysis of NFR-8 and FR-PVC the highest decomposition flaming smoke density range of NFR-8 and FR-PVC were 7.2 to 77.5 and 51.1 respectively. Nonflaming smoke density range of NFR-8 and FR-PVC were 100.4 to 112.2 and 126.5 to 398.8. The amount of carbon monoxide generated was found to be much higher in FR-PVC decomposition than in NFR-8 due to incomp1ete combustion of FR-PVC which has high content of carbon in compound.

• 대한한의학회지
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• 제33권1호
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• pp.42-51
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• 2012

Objectives: We measured the density of smoke and harmful gases emitted from burning adhesive indirect moxa. Through the test we aimed to find out if there was an excessive amount of smoke emitted and if it included harmful gases. Methods: 9 types of adhesive indirect moxa were chosen. The buffer layers which do not burn during treatment were removed and 10g of each moxa were made into powder and put into a holder. A smoke density chamber (Smoke Density Chamber FTT. U.K) and Fourier transform infrared spectroscopy (FT-IR I 4001. MIDAC U.S.A.) were used to measure the density of smoke and harmful gases emitted from burning moxa by ISO 5659-2 test. Results: The result of measuring maximum smoke density showed that the regular indirect adhesive moxa (A-F) emitted high density smoke of 172.1-291.4Ds. The smokeless moxas, Seoam moxas, emitted the least amount of 3.4-5.5Ds. Concentrations of 7 typical harmful gases (CO, HCl, HCN, HBr, HF, SO2, NOx) were measured and all of the moxas emitted CO due to incomplete combustion. 4 types of moxa emitted NOx and all smokless moxas emitted NOx. HBr, HCN, HCl, HF, SO2 were not found in any of the moxas. Conclusions: The amount of harmful gases emitted from burning moxa was much lower than short-term exposure standards of chemical and physical factors (Ministry of Labor 2010-44). Further experiments measuring gases from moxa combustion should be done in larger environments similar to normal medical clinics.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.2164.1_2165.1
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• 2009

In this study we suggest fire detection algorithm using fuzzy inference with input variables of temperature and smoke density to detect electrical fire of early stage. The algorithm consists of membership function of temperature and smoke density and fire probability. The antecedent part of the algorithm consists of temperature and smoke density, and the consequent part consists of fire possibility. The inference rules of the algorithm is estimated to input temperature and smoke density obtained by real fire. With the help of algorithms using fuzzy inference we may be diagnose electrical fire precisely.

• 한국안전학회지
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• 제24권4호
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• pp.96-103
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• 2009

This study was fulfilled to investigate the forest fire risk of forest fuels based on the combustion characteristics of living leaves of coniferous trees and broadleaf trees naturally growing in Youngdong areas of Gangwon Province by using cone calorimeter and smoke density chamber. According to the result, Pinus densiflora and Pinus rigida among coniferous trees released a greater amount of heat release than other kinds. The total smoke release varied depending on the species, whereas Pinus koraiensis showed the largest amount of smoke release. With regard to maximum smoke density, it was much higher in coniferous trees than in broadleaf trees. With regard to smoke temperature, Pinus densiflora showed the lowest compared to other kinds up until 200s from the ignition, but all most trees uniformly maintained constant temperature of about $70^{\circ}C$ after 200s. The concentrations of CO and $CO_2$ release were drastically increased at about 150s and then gradually decreased thereafter. Pinus densiflora showed a bit higher CO release than broadleaf trees, but there was no distinct difference in $CO_2$ release among tress.

• 한국응용과학기술학회지
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• 제30권1호
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• pp.1-8
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• 2013

알킬렌디아미노 기능기를 분자 내에 갖는 4종의 새로운 알킬렌디아미노알킬-비스-포스폰산 유도체들을 합성하고, 그들의 연기밀도를 측정하였다. 이 화합물들은 알킬렌디아민 및 알데히드에 인산을 첨가하여 한 단계로 반응시켜 2개의 인산에 2개의 아미노기를 갖는 화합물로서 76~97.3%의 수율을 얻었다. 이들의 연기밀도 시험은 ASTM E 662의 방법으로 측정하였으며, 시험결과 연기밀도(Ds)값이 234.7~437.9으로 측정되었고, 2개의 인산을 갖는 화합물이 1개의 인산구조를 갖는 화합물보다 연기밀도가 증가되었다. 따라서 하나 또는 두 개의 인산에 결합된 아마노기의 질소수와 연기밀도 사이에는 관련이 있었다.

• 분석과학
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• 제21권3호
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• pp.159-166
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• 2008

본 연구에서는 water/oil 유화연료를 제조하여 제조된 연료의 점도, 밀도, 최적의 조사시간, 유화 안정성 등의 유화연료 특성 및 배기배출물 특성인 NOx, THC, CO의 농도와 smoke density를 측정하였다. 유화연료는 경유, 물, 유화제를 첨가한 후 homogenizer와 초음파 발생장치를 일정시간 조사하여 제조하였고, 배출가스 시험은 2476 cc diesel engine을 사용하여 engine dinamo meter로 실험하였다. 유화연료에서 함수율이 증가할수록 밀도가 증가하였으며, 점도는 함수율 60%까지는 W/O type이 형성되어 증가하다가 70%에서는 O/W type이 형성되어 감소하였다. 배출가스 시험결과 함수율이 증가할수록 NOx 농도와 smoke density는 감소하고, THC와 CO 농도는 증가하였다. 출력감소 시험 결과 함수율이 증가할수록 배출온도와 출력이 감소하였다. 위의 결과로부터 압축착화 디젤기관에 유화연료를 사용하는 것은 NOx와 smoke를 제거하는 효과적인 방법이라고 사료되어진다.

• 한국화재소방학회논문지
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• 제22권3호
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• pp.300-304
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• 2008

고분자 물질의 화재 위험성 및 화재시 인명 피해의 감소를 위한 기초자료로 제시하고자 점토질의 첨가에 의한 난연성 평가를 수행하였다. 본 연구에서는 에폭시 수지의 난연성 향상과 연기의 발생량을 감소시키기 위하여 점토질의 montmorillonite(MMT)와 같은 천연 물질을 삽입하여 연소 특성을 살펴보았다. 이 연구를 위하여 한계산소지수(limiting oxygen index, LOI), 탄화층 생성량(char yield), 연기 밀도(smoke density) 측정 둥의 난연성 실험을 실시하였다. Epoxy/MMT의 복합재료는 MMT의 농도가 증가할수록 한계산소지수 및 탄화층 생성량이 증가하여 난연성이 향상되었으나 연기 밀도는 오히려 증가하는 결과를 나타내었다.