• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.10
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• pp.726-734
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• 2007

In this study, lower flammability limits (LFLs) of three hydrocarbon refrigerants (R600a, R290, R1270) and two hydrofluorocarbon refrigerants (R152a, R32) and DME (RE170) are measured by the method proposed by ASTM E681-04 Standard. Flammability tests are carried out at three temperatures of $23^{\circ}C,\;60^{\circ}C\;and\;100^{\circ}C$ and relative humidity 50%. Test results show that the present data for isobutane and propane obtained at $23^{\circ}C$ are similar to those found in the literature, confirming indirectly the reliability of the present test method and facility. For propylene, R152a, and R32, LFLs found in the literature differ considerably. Especially, the deviation of LFL of propylene is more than 30% among the literature data. The present data for propylene, R152a, and R32 agree with either of the data sets available. As the temperature increases from $23^{\circ}C\;to\;100^{\circ}C$, LFLs of all refrigerants tested decrease. LFLs of most refrigerants tested in this study at $60^{\circ}C$ decrease by $0.1{\sim}0.3%$ as compared to those at $23^{\circ}C$. Also LFLs of most refrigerants tested in this study at $100^{\circ}C$ decrease by $0.1{\sim}0.3%$ as compared to those at $60^{\circ}C$.

• Journal of the Korean Ceramic Society
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• v.22 no.4
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• pp.54-60
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• 1985

Gas sensing materials for detecting flammable gases such as $CH_4$, $C_3H_8$ and n-$C_4H_{10}$ were developed by util-izing $In_2O_3$ as the principal sensing material. The sensing materials were formulated by mixing $In_2O_3$ powder with one or two other chemicals such as $SnO_2$, $Y_2O_3$ and $Al_2O_3$ with a small addition of $PdCl_2$ as a catalyst. Sample of sensor were fabricated by coating each of the mixtures on a ceramic tube impregnating ethylsili-cate and firing at 75$0^{\circ}C$ Each material mixture was evaluated by measuring and comparing gas sensitivity(resistance in air/resistance with gas) to flammable gases such as $CH_4$, $C_3H-8$ and n-$C_4H_{10}$. It was found that among fifteen compositions tested three compositions as follows show the highest gas sensitivity and thus are very feasible for commercialization as the gas sensors ; o49.5 $In_2O_3$+50 Al2O3_0.5 PdCl2(wt%) o $20In_2O_3+29$ $SnO_2+50$ $Al_2O_3+1$ $PdCl_2$(wt%) o40 $In_2O_3$+9 $Y_2O_3+50$ $Al_2O_3+1$ $PdCl_2$(wt%)

• Fire Science and Engineering
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• v.20 no.1 s.61
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• pp.1-5
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• 2006

The spontaneous ignition of a flammable matter is a crucial factor for the prevention of a fire. The minimum ignition temperatures of Gasoline and Cenox in $1000{\mu}l$ of a sample were determined to be $340.5^{\circ}C\;and\;368.5^{\circ}C$ respectively. In addition when the time taken for ignition was 1.0 sec, the instantaneous ignition temperatures were $416^{\circ}C\;and\;427^{\circ}C$ respectively. Moreover, the changes in the minimum ignition temperature were small when less than 60 v/v% of Cenox was added, but the changes were great when 80 v/v% or more was added. Therefore, it is hypothesized that, when used as a fuel in the Gasoline engine, the ratio of the mixture of Cenox and Gasoline will be a very important factor.

• Journal of Convergence for Information Technology
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• v.10 no.6
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• pp.77-86
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• 2020

A thin and porous non-flammable wiper was prepared by phosphorus acid solution treatment and subsequent oven annealing. The H₃PO₃ treatment improved flame retardancy of wiper paper to nonflammable level. Thermogravimetric analyses showed that residues increased to 50% at 700℃, which means this treatment helps dehydration of the cellulose chain and promotes the formation of char-like structures during the burning. FT-IR and X-ray photoelectron spectroscopy showed that some of the added H₃PO₃ could react with the functional groups of the cellulose chain. The reacted H₃PO₃ components promote dehydration of the cellulose components and the formation of a char-like structure and improve the flame retardancy of the wiper paper.

• Journal of Trauma and Injury
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• v.30 no.4
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• pp.145-157
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• 2017

Purpose: We accessed epidemioloy of 908 acute burns (7 years) in the military, of injuries and propose proper educational programs to suit community. Methods: We surveyed burn demographics, circumstances of injuries, size, result of treatment. Results: The mean age was 20.6 years. The flame burns (FB) (325, 35.8%) were most common, followed scald (SB) (305, 33.6%), contact (CB) (219, 24.1%), electric (EB) (45, 5.0%) and chemical burns (ChB) (14, 1.5%). The more occurred during winter (29.7%). SB had mean 3.9% total body surface area (TBSA). The 251 (82.3%) had superficial burns by spillage of hot water/food on lower limbs (45.6%), feet (33.8%) in summer (34.8%), treated with simple dressing (92.8%). Morbidity rate was 5.6%; post traumatic stress disease (PTSD) (0.7%). FB had large wound (9.3% TBSA). The 209 (64.3%) had superficial burns by ignition to flammable oils (31.7%) and bomb powders (29.2%) on head/neck (60.3%), hands (58.6%) in summer (31.7%), autumn (30.2%). They underwent simple dressing (83.4%) and skin graft (16.0%). Morbidity rate was 18.8%; PTSD (10.5%), inhalation injuries (4.0%), corneal injury (3.7%), amputations (0.9%), and mortality rate (1.2%). CB had small (1.1% TBSA), deep burns (78.5%) by hotpack (80.4%) on lower limbs (80.4%). The more (59.8%) underwent skin graft. EB had 6.8% TBSA. The 29 (64.4%) had superficial burns by touching to high tension cable (71.1%) on hand (71.1%), upper limbs (24.4%) in autumn (46.8%). They underwent simple dressing (71.1%) and skin graft (24.4%). They showed high morbidity rate (40.0%); loss of consciousness (13.3%), nerve injuries (11.1%), neuropathy (8.9%), amputations (2.2%), and mortality rate (2.2%). Conclusions: The cook should wear apron over the boots during work. The lighter or smoking should be strictly prohibited during work with flammable liquids or bomb powders. Don't directly apply hotpack to skin for a long time. Use insulating glove during electric work. Keep to the basic can prevent severe injury and proper education is important.

• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.3-5
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• 2008

An increase in oil and gas plants caused by development of process industry have brought into the increase in use of flammable and toxic materials in the complex process under high temperature and pressure. There is always possibility of fire and explosion of dangerous chemicals, which exist as raw materials, intermediates, and finished goods whether used or stored in the industrial plants. Since there is the need of efforts on disaster damage reduction or mitigation process, we have been conducting a research to relate explosion model on the background of real 3D terrain model. By predicting the extent of damage caused by recent disasters, we will be able to improve efficiency of recovery and, sure, to take preventive measure and emergency counterplan in response to unprepared disaster. For disaster damage prediction, it is general to conduct quantitative risk assessment, using engineering model for environmental description of the target area. There are different engineering models, according to type of disaster, to be used for industry disaster such as UVCE (Unconfined Vapour Cloud Explosion), BLEVE (Boiling Liquid Evaporation Vapour Explosion), Fireball and so on, among them, we estimate explosion damage through UVCE model which is used in the event of explosion of high frequency and severe damage. When flammable gas in a tank is released to the air, firing it brings about explosion, then we can assess the effect of explosion. As 3D terrain information data is utilized to predict and estimate the extent of damage for each human and material. 3D terrain data with synthetic environment (SEDRIS) gives us more accurate damage prediction for industrial disaster and this research will show appropriate prediction results.

• Fire Science and Engineering
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• v.18 no.3
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• pp.57-73
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• 2004

Quantitative safety analysis through a fault tree method has been conducted for a fire broken out over the spilling LNG from a pilot LNG tank, which may have 4 types of scenarios causing potentially risky results. When we consider LNG release from venting pipelines as a first event, any specific radius of Low Flammable Limit(LFL) has not been built up. The second case of LNG outflow from the rupture of storage tank which will be the severest has been analyzed and the results revealed various diffusion areas to the leaking times even with the same amount of LNG release. As a third case LNG leakage from the inlet/outlet pipelines was taken into consider. The results showed no significant differences of LFL radii between the two spilling times of 10 and 60 minutes. Hence, we have known the most affecting factor on the third scenario is an initial amount of LNG release. Finally, the extent of LFL was calculated when LNG pipelines around the dike area were damaged. In addition, consequence analysis has been also performed to acquire the heat radiation and flame magnitude for each case.

• Journal of the Korean Society of Combustion
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• v.20 no.1
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• pp.6-14
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• 2015

Numerical study was conducted to clarify effects of added $H_2O$ for the downstream interaction between $H_2$-air and CO-air premixed flames in counterflow configuration. The reaction mechanism adopted was Davis model which had been known to be well in agreement with reliable experimental data. The results showed that both lean and rich flammable limits were reduced in increase of strain rate. The most discernible difference between the two with and without having $H_2O$ and/or $H_2$ addition into $H_2$-air and CO-air premixtures was two flammable islands for the former and one island for the latter at high strain flame conditions. Even a small amount of $H_2$, in which $H_2$-air premixed flame cannot be sustained by itself, participates in CO oxidation, thereby altering the CO-oxidation reaction path from the main reaction route $CO+O_2{\rightarrow}CO_2+O$ with a very long chemical time in CO-air flame to the OH-related reaction routes including $CO+OH{\rightarrow}CO_2+H$ with very short chemical times. This intrinsic nature alters flame stability maps appreciably. The results also showed that chemical effects of added $H_2O$ help lean flames at relatively low strain rate be sustained, and suppress the flame stabilization at high strain rates.

• Fire Science and Engineering
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• v.31 no.6
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• pp.1-7
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• 2017

Currently, flammable liquids account for more than 87 wt% of the hazardous materials in circulation in Korea, and paint products are the most commonly used mixed hazardous materials. Therefore, one of the most urgent and important issues is that we have to secure the safety for manufacturing, storage and transport of paint products. In this study we investigated and analyzed the domestic hazardous materials safety management method, the international GHS test method and so forth. We tested risks for a variety of oil paints and found a relation between the results. Furthermore, the risk test method and criteria adapted for domestic situation was presented. Paints were classified as hazardous or non-hazardous according to the results of the flash point test, the amount of flammable liquid or the UN-combustion persistence test. It was revealed from the test results of 6 kind of oil-based paints using different resins that they were hazardous materials with very high risks and belonged to the Category 1 or the Category 2.

• Journal of Energy Engineering
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• v.24 no.4
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• pp.18-23
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• 2015

The flash point is used to categorize inflammable liquids according to their relative flammability. The flash point is important for the safe handling, storage, and transportation of inflammable liquids. The flash point temperature of two binary liquid mixtures($CCl_4+o-xylene$ and $CCl_4+p-xylene$) has been measured for the entire concentration range using Tag open cup tester. The flash point temperature was estimated using Raoult's law, UNIQUAC model and empirical equation. The experimentally derived flash point was also compared with the predicted flash point. The empirical equation is able to estimate the flash point fairly well for $CCl_4+o-xylene$ and $CCl_4+p-xylene$ mixture.