• Journal of Soil and Groundwater Environment
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• v.27 no.2
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• pp.50-60
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• 2022

The concentration levels and distribution characteristics of 16 polycyclic aromatic hydrocarbons (PAHs) were investigated and evaluated for total 100 soil samples as a part of the survey on soil contamination in Gwangju. The results (median and range) of T-PAHs (sum of 16 PAH concentrations), C-PAHs (sum of carcinogenic PAH concentrations) and T-TEQs (sum of 16 TEQ concentrations) were 20.8 (7.6~1158.1), 2.2 (N.D~509.6), and 0.3 (N.D~424.6) ㎍/kg, respectively. There was a positive correlation between C-PAHs/T-PAHs and T-TEQs/T-PAHs except one point where the concentration of benzo(a)pyrene was high. The ratios of the C-PAHs/T-PAHs were 31.7% for low molecular weight-PAHs and 68.3% for high molecular weight-PAHs, suggesting that PAHs generation mainly arose from combustion sources. The ratio of isomers of individual PAHs, Phe/Ant, Flu/Pyr, Ant/(Ant+Phe), Flu/(Flu+Pyr), and BaA/(BaA+Chr), also confirmed the predominance of PAHs from combustion activities. Statistical tracing of the source of PAHs through principal component analysis indicated that the main sources of combustion were automobile fuel and coal. The overall results of this study suggested HMW-PAHs, T-PAHs, C-PAHs and T-TEQs should be separately evaluated to better assess the toxicity and environmental behavior of individual PAHs.

• Fire Science and Engineering
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• v.16 no.1
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• pp.18-23
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• 2002

Efficiency estimation of toxicity free resistance cable experiments were conducts to understand toxicity free fire ersistance polyolefin insulation material and smoke density characteristic and combustion gas corrosion analysis. A main cause of fire-growth and generating toxic gas when it burns, should be dealt with great care in life safety design. Similar patterned fire incidents such as, Inchon Live-Hof Pub Restaurant as, Sea-land Children Resort have proven that serious loss of lives were caused by hazardous gas generated fire resistance cable materials. In this paper, 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$\pm40.04〔w/$\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 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. Also, the fire gases was occurred carbon monoxide and decomposition than in polyolefin due to incomplete combustion of PVC which has high content of carbon in chemical compound.

• 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.

• Fire Science and Engineering
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• v.17 no.2
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• pp.35-42
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• 2003

In this study, we tried to evaluate the ignitibility, flammability, heat release rate, and toxicity of five different types of burning artificial leather sofa covers that are widely used in entertainment service industry buildings. As the results of this study, putting the artificial leathers under fire conditions we found out following results auto-ignition temperature was$ 427~437^{\circ}C$, limiting oxygen index was 19~20%; at heat flux of $25 kW\m^2$, ignition time was 10~16s and peak heat release rate was $147~277 kW\m^2$; and at heat flux of$ 35 kW\m^2$, ignition time was 6~9s and peak heat release rate was $176~296 kW\m^2$. The toxic materials discharged from the burning leathers were 5,550~6,290 ppm of CO, 18,500~23,400 ppm of $CO_2$, 110~140 ppm, of HCl, 13~65 ppm of HCN and 145~220 ppm of NOx.

• Fire Science and Engineering
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• v.28 no.6
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• pp.8-12
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• 2014

Interior finishing materials using noncombustible were regulated by the building codes to prevent the spread of fire and protect occupants. The average deed of stopping time of experimental mouse exposing combustion gas were measured by KS F 2271 gas toxicity test. At that time, The average deed of stopping time under 9 minutes were judged a inconsistence. This experiment method has limit to find out a cause of toxicity effect factor. In this study, particle size analysis were performed for investigate a major factor.

• Journal of the Korean Chemical Society
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• v.39 no.7
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• pp.513-523
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• 1995

Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) are the most concerned toxic organic pollutants to human. Because of their extremely high toxicity and uncertain genotoxic potential, their determination in environmental and biological samples is of great interest. Municipal solid waste incinerator facilities have been reported as the major contributors of dioxins and furans to the environment, and their formation from combustion is a universal phenomenon, everywhere. In this study dioxins and furans were analyzed from the bottom ash produced during combustion in an municipal waste incinerator located in Seoul. The EPA method was modified for sample pretreatment: the soxhlet method was used for extraction and clean-up procedures were performed by using silica and basic alumina, excluding active-carbon. The extract was then analyzed by HRGC/HRMS. A general trend of increase in the amounts of 6∼7 chlorine-substituted dioxins and furans was observed. Total dioxins, furans and 2,3,7,8-TCDD were determined as 8.05 ng/g, 4.75 ng/g, and 6.93 pg/g, respectively.

• Journal of the Korean Institute of Gas
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• v.13 no.3
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• pp.49-53
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• 2009

Relief systems can improve the process safety because it has the function for the prevention of overpressure. Flare stacks is necessary to avoid explosion, radiation, or toxicity by waste-gas emitted from relief system. Safe combustion is one of the important factors to improve safety and the quantity and velocity emitted is ruled in the API code 521. Due to the pressure of released gas and mass flow, a flame from flare stack is similar to jet fire. In this study, we have investigated the effect of flame form on complete combustion and heat emission. API code was similar to jet fire model in flame length, the flame had an effect on the ground.

• Fisheries and Aquatic Sciences
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• v.10 no.2
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• pp.93-101
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• 2007

Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were determined in marine sediments from Mokpo coastal water of Korea. Total and toxic equivalent (TEQ) concentrations of PCDD/Fs ranged from 19.4 to 175pg/g dry weight and ranged from 0.195 to 2.87 pg WHO-TEQ/g dry weight, respectively. These PCDD/F concentrations were below the safety sediment value (20 pg TEQ/g dry weight) of chronic toxicity. A highly significant correlation between the concentrations of PCDD/Fs and total organic carbon (TOC) in marine sediments was observed. Overall PCDD/F concentrations in the sediments were elevated in rivers and at inner locations close to harbors, indicating that these contaminants derived from local discharges of human activities. PCDD/F concentrations measured in our study were lower than those in several industrialized areas in Korea. Nonparametric multidimensional scaling (MDS) ordination showed that combustion processes from industrial complexes are the major source of PCDD/Fs in Mokpo coastal water.

• Journal of Environmental Science International
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• v.27 no.11
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• pp.947-956
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• 2018

Trains have been a major means of transport in Korea during these past decades. However, train facilities such as stations and repair shops are contaminated with organic and inorganic substances. There is a high probability of train facility contamination with polyaromatic hydrocarbons (PAHs). This study evaluated the PAH and heavy metal contamination of soil near railroads in the Kyungpook area. A total of 18 soil samples were collected from the railroads and analyzed for 16 PAHs and 6 heavy metal species. The contamination level of the top soil was found to be slightly higher than that of the subsoil for contamination with PAHs. The ratio of carcinogenic PAH concentration to the total PAH concentration was relatively high, with a maximum of 0.9. The toxicity equivalent (TEQ) of the PAHs were 500.6 ng/kg in the topsoil and 355.5 ng/kg in the subsoil. The ratio of low molecular PAHs (LPAHs) to high molecular PAHs (LPAHs) ranged from 6.7 to 29.5; this shows that contamination is primarily due to combustion of fuel rather than due to petroleum. The ratio of phenanthrene to anthracene and the ratio of fluoranthene to pyrene also show that contamination occurred due to combustion for transportation. The heavy metal contamination level was lower than the Korean standard, but higher than the background concentration; this indicates that the soil was affected by the operation of the railways.

• Fire Science and Engineering
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• v.16 no.2
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• pp.14-21
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• 2002

The several floor finishing materials that widely used in entertainment service industry buildings were evaluated according to the method of NES 713. Also, toxic gases of floor finishing materials in combustion without air flow rate were checked as concentration of fire gases variation according to time using gas analyzer. We had estimated the smoke hazard of floor finishing materials in fire. As results of gas analyses using the method of NES 713, toxic index of samples was estimated range of 2～9.7. Therefore, a large amount of toxic gases will release from a floor finishing materials fire and connoted great smoke hazard in fire.