• Title/Summary/Keyword: Chemical hazards

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Assessment of Autoxidative Resistance for Organic Solvent by Pressure Monitoring Test

  • Kito, Hayato;Fujiwara, Shintaro;Kumasaki, Mieko;Miyake, Atsumi
    • International Journal of Safety
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    • v.9 no.1
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    • pp.43-46
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    • 2010
  • In the recycle process of organic solvent, the atmospheric oxygen can cause autoxidation and product peroxide. The time-saving method to evaluate the hazards has been required. In this study, oxygen pressure monitoring experiment was proposed as a new method to evaluate autoxidative resistances of solvents. Some of organic solvents were pressurized by oxygen and kept under isothermal condition. At the same time, the pressure in the vessel tracked. Iodometrical titration, thermal analysis and spectroscopic analysis were performed to measure peroxide concentration, the heat of reaction and chemical bonding change. From the results that THF has larger oxygen consumption rate than CPME, it is considered that autoxidative resistance of THF is lower than that of CPME. This method enables to obtain results in shorter time than other methods. These experimental results were consistent with the previous research with longer test durations [1-2].

The Cause of Whitening by Flame Retardants Treatment on Korean Wooden Cultural Heritage

  • Kim, Jin Qyu;Chung, Yong Jae;Lee, Hwa Soo;Seo, Hyun Jeong;Son, Dong Won;Han, Gyu-Seong
    • Journal of the Korean Wood Science and Technology
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    • v.44 no.4
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    • pp.589-599
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    • 2016
  • Korean wooden cultural heritages are treated by flame retardants to protect fire hazards. Two types of flame retardants are used to treat wooden cultural heritage. These flame retardants cause some problems such as surface whitening, discoloration, and cracks due to the chemical reaction caused by Korean traditional wood painting (Dancheong), flame retardant and wood humidity. The Korean government is trying to cut down on the amount of flame retardants for the wooden cultural heritage because of these problems. This study was carried out to find the cause of whitening by flame retardants treatment. The reaction between pigment and flame retardant chemicals was analyzed by infrared spectroscopy.

Advances in the Development and Validation of Test Methods in the United States

  • Casey, Warren M.
    • Toxicological Research
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    • v.32 no.1
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    • pp.9-14
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    • 2016
  • The National Toxicology Program Interagency Center for the Evaluation of Alternative Toxicological Methods (NICEATM) provides validation support for US Federal agencies and the US Tox21 interagency consortium, an interagency collaboration that is using high throughput screening (HTS) and other advanced approaches to better understand and predict chemical hazards to humans and the environment. The use of HTS data from assays relevant to the estrogen receptor signaling data pathway is used as an example of how HTS data can be combined with computational modeling to meet the needs of US agencies. As brief summary of US efforts in the areas of biologics testing, acute toxicity, and skin sensitization will also be provided.

Estimation of Explosion Limits by Using Heats of Combustion for Esters (에스테르류의 연소열을 이용한 폭발한계의 예측)

  • Ha, Dong-Myeong
    • Fire Science and Engineering
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    • v.24 no.3
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    • pp.66-71
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    • 2010
  • In order to evaluate the fire and explosion involved and to ensure the safe and optimized operation of chemical processes, it is necessary to know combustion properties. Explosion limit is one of the major combustion properties used to determine the fire and explosion hazards of the flammable substances. In this study, the lower explosion and upper explosion limits of esters were predicted by using the heat of combustion. The values calculated by the proposed equations agreed with literature data within a few percent. From the given results, using the proposed methodology, it is possible to predict the explosion limits of the other ester flammable substances.

Flash Points of Water+n-Propanol System Using Closed-Cup Measurement Apparatus (밀폐계 측정장치를 이용한 물-노말프로판올 계의 인화점)

  • Ha, Dong-Myeong;Choi, Yong-Chan;Lee, Sung-Jin
    • Journal of the Korean Society of Safety
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    • v.17 no.4
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    • pp.140-145
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    • 2002
  • The Flash Point is one of the most important combustible properties used to determine the potential for fire and explosion hazards of chemical materials. An accurate knowledge of the flash point is important in developing appropriate preventive and control measures in industrial fire protection. The lower flash points for the Water + n-Propanol systems were measured by using Pensky-Martens closed cup tester. The experimental data were compared with the values calculated by the laws of Raoult and van laar equation. The calculated values based on the van Laar equation were found to be better than those based on the Raoult's law.

Prediction of Upper Explosion Limits(UEL) by Measurement of Upper Flash Points for n-Alkanes and Aromatic Compounds (노말알칸류와 방향족탄화수소류의 상부인화점 측정에 의한 폭발상한계의 예측)

  • Ha, Dong-Myeong
    • Journal of the Korean Society of Safety
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    • v.26 no.4
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    • pp.59-64
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    • 2011
  • Explosion limit and flash point are the major combustion properties used to determine the fire and explosion hazards of the flammable substances. In this study, in order to predict upper explosion limits(UELs), the upper flash point of n-alkanes and aromatic compounds were measured under the VLE(vapor-liquid equilibrium) state by using Setaflash closed cup tester(ASTM D3278). The UELs calculated by Antoine equation and chemical stoichiometric coefficient tusing the experimental upper flash point were compared with the several reported UELs. From the given results, using the proposed experimental and predicted method, it is possible to research the upper explosion limits of the other flammable substances.

Prediction of Explosion Limits Using Normal Boiling Points and Flash Points of Alcohols Based on a Solution Theory (용액론에 근거한 표준끓는점과 인화점을 이용한 알코올류의 폭발한계 예측)

  • Ha Dong-Myeong
    • Fire Science and Engineering
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    • v.19 no.4 s.60
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    • pp.26-31
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    • 2005
  • In order to evaluate the fire and explosion involved and to ensure the safe and optimized operation of chemical processes, it is necessary to know combustion properties. Explosion limit is one of the major combustion properties used to determine the fire and explosion hazards of the flammable substances. In this study, the explosion limits of alcohols were predicted by using the normal boiling points and the flash points based on a solution theory. The values calculated by the proposed equations agreed with literature data within a few percent. From the given results, using the proposed methodology; it is Possible to Predict the explosion limits of the other flammable substances.

Prediction of Explosion Limits of Organic Halogenated Hydrocarbons by Using Heat of Combustions (연소열을 이용한 유기할로겐화탄화수소류의 폭발한계의 예측)

  • Ha, Dong-Myeong
    • Fire Science and Engineering
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    • v.26 no.4
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    • pp.63-69
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    • 2012
  • Explosion limit is one of the major combustion properties used to determine the fire and explosion hazards of the flammable substances. In this study, the lower explosion limit (LEL) and upper explosion limit (UEL) of organic halogenated hydrocarbons were predicted by using the heat of combustion and chemical stoichiometric coefficients. The calculated explosion limits by the proposed equations agreed with literature data within a few percent. From the given results, using the proposed methodology, it is possible to predict the explosion limits of the other organic halogenated hydrocarbons.

Exposure Assessment in Risk Assessment

  • Herrick Robert F.
    • 대한예방의학회:학술대회논문집
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    • 1994.02a
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    • pp.426-430
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    • 1994
  • The assessment of exposure is an important component of the risk assessment process. Exposure information is used in risk assessment in at least two ways: 1) in the identification of hazards and the epidemiologic research investigating exposure-response relationships and 2) in the development of population exposure estimates. In both of these cases, the value of a chemical risk assessment is enhanced by improvements in the quality of exposure assessments. The optimum exposure assessment is the direct measurement of population exposure; however, such measurements are rarely available. Recent developments in methods for exposure assessment allow estimates to be made that are valid representations of actual exposure. The use of these exposure estimates to classify exposures correctly enhances the likelihood that causal associations between exposure and response will be correctly identified and that population risks will be accurately assessed.

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Study on the Establishment of a Safety Allowance Level of Disastrous and Hazardous Facilities in Large Cities (대도시 위해.위험시설에 대한 안전도 수용기준 정립에 관한 연구)

  • 고재선;윤명오
    • Fire Science and Engineering
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    • v.15 no.1
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    • pp.84-92
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    • 2001
  • In today's world, rise in the establishment of social infrastructure resulting from population saturation in large cities has led to more extensive and frequent use of chemical materials on facilities. A result, unexpected and serious accidents, hazards, contingencies and disasters are more prevalent than ever. Such phenomenon calls for more devoted and concerted efforts towards finding ways to reduce the safety hazards that are seen to take place more often than before with the increase in the number of facilities that are prone to bring disaster and hazard coupled with the conventional safety problems that continue to exist even today. In developed countries, such challenge is addressed by various appropriate countermeasures drawn up by local professional committees on industrial facilities, whose members conduct offsite and onsite evaluation un the potential industrial disasters and its seriousness and provide their advice thereof. Against this backdrop, this study aims at identifying a comprehensive safety allowance level (safety acceptable level) when imposing limitation on the development of conventional or new facilities, for the fur pose of establishing a safety allowance level of disastrous and dangerous facilities in Korea. This is done by assessing and applying the level of danger each individual is exposed to in a randomly selected region (disastrous and dangerous areas in Seoul) based on probability of quantitative hazards, as well as simulation and calculation methods which include: i) social disaster evaluation method applying Quantified Risk Assessment of Health & Safety Executive of UK and Matrix of Risk of Evaluated Sources of Hazard; ii) Fault Tree or Event Tree Analysis and etc.

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