• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 추계학술대회 논문집(III)
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• pp.327-332
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• 2003

We investigated the fire characteristics of the subway electric car's interior materials and evaluated the safety of it. The testing methods are ISO 4589-2 for Limited Oxygen Index, ISO 5658-2 for surface flame spread, ISO 5660-1 for Heat Release Rate, ASTM E 662 for smoke density and BS 6852 Annex B.2 for gas toxicity. The materials of seven organization including KNR were tested. Most of the materials are under the levels of the foreign country's demand. We also reported the test methods of other countries and compared it to ours.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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• pp.178-184
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• 1997

The cone calorimeter as defined by ISO 5660, ASTM 1354, and NFPA 264A is used to assess the reaction to fire of almost any material that must be evaluated in the fire science field. Typical combustion gas analyses include oxygen, CO and CO2. Oxygen consumption is used to determine rate of heat release. Analysis of combustion gases other than oxygen, CO and CO2 has been attempted using filters to remove the solid smoke particles before analysis. This method has generated unreliable results due to the adsorption of many gas components on the active carbon . particles deposited on the filters. A technique using fourier Transform Infrared (FTIB) analysis without filtration will be disclosed and a discussion will be presented of the analytical results of toxic gases produced from various flame retarded polymeric materials. Use of such data in lethal toxic potency determinations is also reviewed.

• 한국가스학회지
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• 제26권3호
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• pp.27-37
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• 2022

최근 ESS(전기저장장치)의 보급이 늘어나면서 ESS에 의한 지속적인 화재발생으로 인명 및 재산의 피해 또한 급증하고 있다. ESS에 활용되는 우레탄 샌드위치 패널에 제조에 있어 난연 성능의 향상이 필요한 실정이다. 본 연구에서는 연질 폴리우레탄 폼의 난연 특성을 구현하고자 제품의 물성을 변화시키는 이소시아네이트 관능기 파라미터의 변화로 인한 제품의 조직 치밀도가 화재성능에 미치는 영향을 연구하였다. 우레탄 조직의 치밀도를 변화시켜가며 제품을 제작하여 연소성능 시험, 가스유해성 시험, 연기밀도 시험을 진행하였다. 그 결과 총 방출열량은 이소시아네이트 관능기 그룹이 높은 경우 성능이 우수하고, 최대 열 방출율과는 상관이 없는 것을 확인하였다. 이소시아네이트 관능기 그룹의 값이 2.7이상에서 형상의 붕괴를 방지할 수 있었다. 가스유해성 시험에서는 이소시아네이트 관능기 그룹이 상대적으로 높아 조직이 치밀하면서 탄화 막 형성이 용이한 Char시스템용 난연제가 추가적으로 투입되어야 성능이 상승하였고, 연기밀도 시험에서는 이소시아네이트 관능기 그룹의 값이 2.75이상에서 성능이 증가되는 것을 확인하였다. 따라서 본 연구의 결과로 기존에 사용되던 저렴한 우레탄 샌드위치 패널을 대체할 난연제 개발에 기반을 마련할 수 있을 것으로 생각된다.

• 한국화재소방학회논문지
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• 제23권6호
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• pp.1-9
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• 2009

본 연구에서는 나일론, 폴리프로필렌, PTT(poly(trimethylene terephthalate)), 양모(wool), 그리고 나일론/양모로 이루어진 5 종류의 카페트에 대한 연소거동을 열류량 $50kWm^2$의 콘 칼로리미터를 이용하여 평가하였으며, 가스유해성 평가는 KS F 2271의 시험방법에 따라 평가하였다. 콘 칼로리미터 실험결과 나일론 카페트는 쉽게 불이 붙는 것을 알 수 있었다. 점화 정도 혹은 초기 가연성은 나일론/양모로 이루어진 카페트가 가장 높은 값을 나타냈다. 불의 세기인 열방출량은 폴리프로필렌 카페트가 가장 큰 것으로 나타났다. 나일론 카페트가 가장 높은 연기 발생량을 보인 반면, 나일론/양모로 이루어진 카페트는 가장 낮은 가스 발생량을 나타냈다. 질량 감소율은 나일론/양모 >양모 >나일론 >폴리프로필렌 >PTT 카페트 순으로 나타났다. 연소 시 발생하는 유해성 가스인 일산화탄소의 경우 PTT에서 가장 많은 발생량을 보였으며, 나일론과 양모로 이루어진 카페트에서 가장 적은 양이 발생됐다. 이산화탄소의 발생량은 폴리프로필렌이 가장 높았으며, 나일론/양모 카페트에서 가장 낮은 값을 나타냈다. 쥐의 행동정지시간을 통해 살펴 본 결과 카페트류의 가스유해성은 PTT 카페트가 가장 해로운 것으로 나타났다.

• Molecular & Cellular Toxicology
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• 제1권4호
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• pp.230-236
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• 2005

Formaldehyde is a common environmental contaminant found in tobacco smoke, paint, garments, diesel and exhaust, and medical and industrial products. Formaldehyde has been considered to be potentially carcinogenic, making it a subject of major environmental concern. However, only a little information on the mechanism of immunological sensitization and asthma by this compound has been known. So, we performed with Jurkat cell line, a human T lymphocyte, to assess the induction of DNA damage and to identify the DEGs related to immune response or toxicity by formaldehyde. In this study, we investigated the induction of DNA single strand breaks by formaldehyde using single cell gel electrophoresis assay (comet assay). And we compared gene expression between control and formaldehyde treatment to identify genes that are specifically or predominantly expressed by employing annealing control primer (ACP)-based $GeneFishing^{TM}$ method. The cytotoxicity ($IC_{30}$) of formaldehyde was determined above the 0.65 mM in Jurkat cell in 48 h treatment. Based on the $IC_{30}$ value from cytotoxicity test, we performed the comet assay in this concentration. From these results, 0.65 mM of formaldehyde was not revealed significant DNA damages in the absence of S-9 metabolic activation system. And the one differentially expressed gene (DEG) of formaldehyde was identified to zinc finger protein 292 using $GeneFishing^{TM}$ method. Through further investigation, we will identify more meaningful and useful DEGs on formaldehyde, and then can get the information on the associated mechanism and pathway with immune response or other toxicity by formaldehyde exposure.

• Toxicological Research
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• 제30권3호
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• pp.149-157
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• 2014

Smoking is one of the most serious but preventable causes of cardiovascular disease (CVD). Key aspects of pathological process associated with smoking include endothelial dysfunction, a prothrombotic state, inflammation, altered lipid metabolism, and hypoxia. Multiple molecular events are involved in smoking-induced CVD. However, the dysregulations of reactive oxygen species (ROS) generation and metabolism mainly contribute to the development of diverse CVDs, and NADPH oxidase (NOX) has been established as a source of ROS responsible for the pathogenesis of CVD. NOX activation and resultant ROS production by cigarette smoke (CS) treatment have been widely observed in isolated blood vessels and cultured vascular cells, including endothelial and smooth muscle cells. NOX-mediated oxidative stress has also been demonstrated in animal studies. Of the various NOX isoforms, NOX2 has been reported to mediate ROS generation by CS, but other isoforms were not tested thoroughly. Of the many CS constituents, nicotine, methyl vinyl ketone, and ${\alpha}$,${\beta}$-unsaturated aldehydes, such as, acrolein and crotonaldehyde, appear to be primarily responsible for NOX-mediated cytotoxicity, but additional validation will be needed. Human epidemiological studies have reported relationships between polymorphisms in the CYBA gene encoding p22phox, a catalytic subunit of NOX and susceptibility to smoking-related CVDs. In particular, G allele carriers of A640G and $-930^{A/G}$ polymorphisms were found to be vulnerable to smoking-induced cardiovascular toxicity, but results for C242T studies are conflicting. On the whole, evidence implicates the etiological role of NOX in smoking-induced CVD, but the clinical relevance of NOX activation by smoking and its contribution to CVD require further validation in human studies. A detailed understanding of the role of NOX would be helpful to assess the risk of smoking to human health, to define high-risk subgroups, and to develop strategies to prevent or treat smoking-induced CVD.

• Tuberculosis and Respiratory Diseases
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• 제74권3호
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• pp.120-123
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• 2013

Inhalation of toxic gases can lead to pneumonitis. It has been known that methane gas intoxication causes loss of consciousness or asphyxia. There is, however, a paucity of information about acute pulmonary toxicity from methane gas inhalation. A 21-year-old man was presented with respiratory distress after an accidental exposure to methane gas for one minute. He came in with a drowsy mentality and hypoxemia. Mechanical ventilation was applied immediately. The patient's symptoms and chest radiographic findings were consistent with acute pneumonitis. He recovered spontaneously and was discharged after 5 days without other specific treatment. His pulmonary function test, 4 days after methane gas exposure, revealed a restrictive ventilatory defect. In conclusion, acute pulmonary injury can occur with a restrictive ventilator defect after a short exposure to methane gas. The lung injury was spontaneously resolved without any significant sequela.

• Asian Pacific Journal of Cancer Prevention
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• 제16권14호
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• pp.5863-5868
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• 2015

Nicotine-derived nitrosamine ketone (NNK) is considered a key tobacco smoke carcinogen inducing lung tumors. Physalis peruviana L (harankash) is considered one plant with marked health benefits. This study aimed to evaluate Physalis peruviana L effect on the toxic effect of NNK induced lung cancer in the rats by using pulmonary histopathological, immunohistochemical and DNA flow cytometric analyses. Sixty adult male rats were divided into four groups, each consisting of fifteen animals. The first group received saline, the second received two successive toxic doses of NNK only while the third received two successive toxic doses of NNK with a single daily dose of Physalis peruviana L. The fourth group received a single daily dose of Physalis peruviana L only. Toxic doses of NNK induced hyperplasia and adenocarcinoma in the lung and positive immunoreactivity for Ki-67 and p53 staining with disturbance of the lung DNA content. Administration of Physalis peruviana L with NNK led to a mild pulmonary hyperplasia and weak expression of Ki-67 and p53 with an improvement in the lung DNA content. Physalis peruviana L may protect against NNK induced lung carcinogenesis due to its antioxidant and anti-proliferative effects.

• 대한임상독성학회지
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• 제13권1호
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• pp.46-49
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• 2015

Carbon monoxide (CO) intoxication is a leading cause of severe neuropsychological impairments. Peripheral nerve injury has rarely been reported. Following are brief statements describing the motor peripheral neuropathy involved bilateral lower extremities of a patient who recovered following acute carbon monoxide poisoning. After inhalation of smoke from a fire, a 60-year-old woman experienced bilateral leg weakness without edema or injury. Neurological examination showed diplegia and deep tendon areflexia in lower limbs. There was no sensory deficit in lower extremities, and no cognitive disturbances were detected. Creatine kinase was normal. Electroneuromyogram patterns were compatible with the diagnosis of bilateral axonal injury. Clinical course after normobaric oxygen and rehabilitation therapy was marked by complete recovery of neurological disorders. Peripheral neuropathy is an unusual complication of CO intoxication. Motor peripheral neuropathy involvement of bilateral lower extremities is exceptional. Various mechanisms have been implicated, including nerve compression secondary to rhabdomyolysis, nerve ischemia due to hypoxia, and direct nerve toxicity of carbon monoxide. Prognosis is commonly excellent without sequelae. Emergency physicians should understand the possible-neurologic presentations of CO intoxication and make a proper decision regarding treatment.

• Composites Research
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• 제14권6호
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• pp.1-8
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• 2001

본 연구에서는 샌드위치 패널 구성 요소인 면재와 심재를 변화시켜 4종류의 샌드위치 패널을 제작하였다. 그리고 제작된 샌드위치 패널의 기계적 특성과 철도차량 개발시 중요한 요인으로 작용하는 음향투과 특성 그리고 화재에서의 안정성을 확인하기 위하여 난연특성 실험을 통하여 샌드위치 패널의 특성을 검토하고자 하였다. 샌드위치 패널의 기계적 특성은 알루미늄 면재 + 알루미늄 하니컴 심재로 구성된 샌드위치 패널이 면방향 인장강도와 변방향 압축강도 특성에서 우수하며 알루미늄 면재 + 노멕스 하니컴 심재로 구성된 샌드위치 패널은 면방향 압축강도와 굽힘 강도가 우수한 것으로 확인되었다. 알루미늄 면재 + PMI 포옴 심재로 구성된 샌드위치 패널은 심재의 전단강도 및 면재의 굽힙강도가 우수하였다. 난연성 시험에서는 phenol 수지 면재와 2종의 외국 면재는 모든 시험 결과에서 유사한 견과를 확인하였다.