• Fire Science and Engineering
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• v.21 no.2 s.66
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• pp.64-73
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• 2007

The absorption characteristics of hazardous materials onto human body and defense mechanism differ from each other region within the respiratory tracts, thus adverse health effects of inhaled smokes are associated with not only the concentration but also the location of the particles deposited. In this work, the deposition fraction per surface area and the deposition sites of the smoke particles in human respiratory tracts for each rest and light exercise conditions together with oral and nasal breathing were calculated by using segmental volume tracking method. The results would be used for deriving the amount of absorption of hazardous materials onto human body, thus contribute to the health risk assessments of inhaled fire smokes.

• Fire Science and Engineering
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• v.33 no.6
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• pp.95-104
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• 2019

Smoke generated in a fire consists of gaseous substances and particulate matter, such as unburned carbon that adsorbed the gases. Human injury caused by inhalation of gaseous substances present in smoke is mostly short-term, whereas damage caused by inhalation of particulate matter is relatively a long-term phenomenon depending on the state of the gas-phase adsorption. The amount and location of the deposited smoke particles are important factors in estimating the damage caused to humans, which are affected by the breathing conditions as well as particle conditions, such as the size and concentration affected by the combustion conditions. In this study, in order to understand the characteristics of the deposition of smoke particles in the respiratory tract related to the study of human smoke inhalation injury, the number and mass concentration of smoke particles deposited in different areas of the respiratory tract for different fuel types, combustion conditions and breathing conditions were calculated. In addition, the amount of mass deposition of smoke in the respiratory tract for a certain period of inhalation was compared with the atmospheric standard of fine dust.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1734-1737
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• 1997

The conventional fire detection devices are operated after a processed fire phase, which are sensing only a high density of somke level or high temperature heat. They are not so precision to detect a fire in the early phase to protect the facility form the fire. We need to develope a new high precision smoke detection system to keep expensive industrial facilities most reliably form fire. A new optical precision smoke detection system was developed. It monitors very low level density of smoke particles in the air. It is operated continously through many years without a stop or any malfunction. The developed precision smoke detection system will be installed in important industrial facilities, such as power plants, underground common tunnel, main control rooms, computer rooms etc.

• Journal of Environmental Science International
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• v.32 no.1
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• pp.37-46
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• 2023

This study investigated the effect of May 31, 2022 Miryang wildfire on fine particle concentrations in Busan and Gimhae, which are neighboring urban areas. In addition, fine particle characteristics and air pollution concentrations were investigated in Miryang, where haze occurred. The Miryang city wildfire that occurred on May 31, 2022, at 0925 LST, was driven by strong north winds and increased fine particle concentrations in Dongsangdong and Jangyoodong, Gimhae City, which are approximately 35 km to the southeast and south, respectively, of the wildfire occurrence site. Furthermore, the fine particle concentration in Myeongjidong, which is approximately 50 km south-southeast of the wildfire site, exhibited a temporary increase at 1400 LST owing to the effects of wildfire smoke. On the morning of June 1, the day after the fire, the Miryang area had very bad visibility because of the smoke from the fire. Therefore the PM₁₀ and PM_2.5 concentrations in Naeildong, 3 km south of the wildfire site, were 276 ㎍/㎥ and 222 ㎍/㎥, respectively, at 1200 LST. In addition, the gases O₃, CO, and SO₂ showed high concentrations at the time of haze generation. This study provides insights into policy making in response to the rapid increase in fine dust when wildfire occurs near cities.

• Journal of the Korean Society of Safety
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• v.28 no.6
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• pp.11-16
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• 2013

This paper presents a study on the analyzing reliability of smoke fire detector using accelerated life test. In general, the smoke fire detector is broken by dust which flow in smoke detection chamber. In order to conduct accelerated life test of smoke fire detector dust is set accelerated factor in this paper. The dust is fly-ash which is test particle 5th regulated by KS A 0090. The dust accelerated level is 60 g, 180 g and 360 g and failure time is measured by smoke sensitivity testing. It is considered to failure of detector if detector don't operate within 30 secconds when subjected to an air stream having a velocity of 20 cm/s~40 cm/s containing smoke with a concentration of 15% of rate of light-response of 1 m. The goodness of fit test and mean life prediction conduct using the failure time. The result show that life distribution fits the weibull distribution for failure time data and the mean lifes calculate 22.5 year in domestic product and 14.7 years in overseas product applied dust stress only.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.5
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• pp.679-685
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• 2009

In order to simulate a smoke or poisonous gas emergency in a rectangular tunnel and to investigate a better way to exhaust the smoke, the characteristics of smoke flow have been analyzed using flow field data acquired by Particle Image Velocimetry(PIV). Olive oil has been used as tracer particles with the kinematic viscosity of air, $1.51{\times}10^{-5}\;m^2/s$. The investigation has done in the range of Reynolds number of 1600 to 5333 due to the inlet velocities of 0.3 m/s to 1 m/s respectively. The average velocity vector and instantaneous kinematic energy fields with respect to the three different Reynolds numbers are comparatively discussed by the Flow Manager. In general, the smoke flow becomes more disorderly and turbulent with the increase of Reynolds number. Kinematic energy in the measured region increases with the increase of Reynolds number while decreasing at the leeward direction about the outlet region.

• Fire Science and Engineering
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• v.17 no.4
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• pp.105-110
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• 2003

In Part II, the temperature and smoke particle distributions of the extraction system, which yielded the best smoke removal performance among the three smoke control systems in Part I, for extraction flowrates of 0.6∼2.4 ㎥/s and two fire sizes of 200 ㎾ and 2 ㎿ were presented. The same numerical method was utilized to the same computational domain and configurations as Part I. It was shown that the extraction flowrate affects the smoke control performance significantly, and that a similar trend in improving the smoke removal performance with the increasing extraction flowrate between the two fire sizes. An extraction flowrate of 2.4 ㎥/s or higher was required for the temperature in the escape route less than $^{\circ}C$ for the given situations.

• Fire Science and Engineering
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• v.28 no.1
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• pp.44-51
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• 2014

Smoke from fire is a mixture of combustion gases and particles which include micro-droplets formed from condensed organic vapors and carbonaceous agglomerates. The inhalation of smoke particles causes adverse health effects, and it is prerequisite for the hazard and risk analysis of the smoke particles to know how they behaviour in the respiratory tract. The characteristics of the absorption and adsorption of toxic gases and the amount and location of the particle deposition within the respiratory tract that determine the adverse health effects are related to the morphology and the size distribution of smoke particles. In the present work, as a preliminary study for the adverse health effects of smoke particles, the morphologies of the smoke particles from combustible materials were investigated for each fire stage: smouldering, well-ventilated flaming, small under-ventilated flaming, fully-developed under-ventilated fire. The steady-state tube furnace method given in ISO/TS 19700 was used for the generation of smoke particles. The fire stages were controlled by changing furnace temperature and equivalent ratio. The morphologies were analyzed by using Transmission Electron Microscope (Bio-TEM) by collecting the particles on TEM grids put on each stage of a cascade impactor.

• Journal of the Korean Society of Safety
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• v.21 no.5 s.77
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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.

• Journal of the Korean Society of Tobacco Science
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• v.20 no.1
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• pp.124-130
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• 1998

This study was conducted to evaluate the ability of anion generating air cleaner to remove gases, vapor and particles from closed room contaminated with environmental tobacco smoke (ETS). The measurements covered particle sizes of 13.8-542.5nm, particle concentration, surface area, volumes UVPM, FPM, solanesol, and the following gases and vapor; carbon dioxide, carbon monoxide, nicotine, and 3-ethenylpyridine. Tobacco smoke was generated and mixed in a closed room in which the airflow rates were in the range of 0.00-0.04 m/s. The anion generating air cleaner was startedl and the decay rates for the gases, vapor and particles were measured, When the use of anion generating air cleaner, solid components of ETS, such as respirable suspended particle (RSP), utraviolet particulate matter (UVPM, fluorescent particulate matter (FPM) and solanesol was sharply decreased, and vapor phase components of ETS, such as nicotines 3-ethenylpyidine were modelately decreased by time elapse. Even the use of anion generation air cleaner, the decreasing rate of carbon dioxide concentration was similar with control, and the decreasing rate of carbon monoxide was slower than that of control. Our results indicated that the use of anion generting air cleaner had an effect on reduction of solid and vapor components from ETs, but it had no effect on gaseous components of ETS.