• Journal of the Korean Society of Safety
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• v.18 no.4
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• pp.148-154
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• 2003

There are now the plating process that have many hazardous factor cause of the using numerous noxious chemical and bad working environments. The purpose of the study is to make a selection of suitable safety evaluation method that can analyze and righteously find with numerous hazardous factor of the plating process. And another purpose is to systematically adjust the risk of plating process by comprehension of the role of process, equipment, and source material. Therefore, these studies are carried out in the following three investigations of this report. The first research understands the injurious human health and environment by analyzing hazardous material based on the MSDS. To evaluate the safety of process and compartment, the second research is proposed the security secure counterproposal by using the FMEA and the HAZOP. The final research is devoted to systematically analyze the hazard by applying for reasonable guide word and doing the HAZOP for hazardous factor in specific process.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.815-818
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• 2008

Titanium was oxidized with oxygen plasma and calcinated with rapid thermal annealing for degradation of humic acid dissolved in water. Titania photocatalytic plate was produced by titanium surface oxidized with oxygen plasma by Plasma Enhanced Chemical Vapor Deposition(PECVD). RF-power and deposition condition is controlled under 100 W, 150 W, 300 W and 500 W. Treatment time was controlled by 5 min and 10 min. The film properties were evaluated by the X-ray Photoelectron Spectroscopy (XPS) and X-Ray Diffraction (XRD). From the experimental results, we found the optimal condition of titania film which exhibited good performance. Moreover photocatalytic capacity was about twice better than thermal spray titania film, and also as good as titania powder.

• Journal of the Korean Society of Safety
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• v.12 no.2
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• pp.87-94
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• 1997

If sodium azide is impinged by certain reasons, it will be produced explosives by heavy metals and toxic materials. But it is used propellent for inflating automotive safety bags and the other chemical manufacturing purpose. The investigation of thermal hazard potential of sodium azide itself and with polymers ate very important because some parts of automotives, transporting vessels of reactive chemicals and many any other constituents of structures in factories are made of polymers. The range of decomposition temperatures are about $360-380^{\circ}C$, even if it depends on heating rate and sample weight. Thermal decomposition heat of sodium azide in air is higher than in nitrogen atmosphere, because the former is included oxidizing heats of sodium metal which is made by decomposition of sodium azide to end. Especially decomposition temperature of polymers are increased on the order of bonding energy between atoms in hydrocarbon moleculars.

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.10b
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• pp.128-128
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• 2003

There are many synthetic chemicals, such as di(2-ethylhexyl) phthalate (DEHP) and dibutyl phthalate (DBP), used in chemical reaction processes in industry. The establishment of toxicity and detection of synthetic chemicals that may pose a genetic hazard in our enviornment is subjects of great concern at present.(omitted)

• Safety and Health at Work
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• v.8 no.3
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• pp.237-245
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• 2017

Background: Solar furnaces are used worldwide to conduct experiments to demonstrate the feasibility of solar-chemical processes with the aid of concentrated sunlight, or to qualify high temperature-resistant components. In recent years, high-flux solar simulators (HFSSs) based on short-arc xenon lamps are more frequently used. The emitted spectrum is very similar to natural sunlight but with dangerous portions of ultraviolet light as well. Due to special benefits of solar simulators the increase of construction activity for HFSS can be observed worldwide. Hence, it is quite important to protect employees against serious injuries caused by ultraviolet radiation (UVR) in a range of 100 nm to 400 nm. Methods: The UV measurements were made at the German Aerospace Center (DLR), Cologne and Paul-Scherrer-Institute (PSI), Switzerland, during normal operations of the HFSS, with a high-precision UV-A/B radiometer using different experiment setups at different power levels. Thus, the measurement results represent UV emissions which are typical when operating a HFSS. Therefore, the biological effects on people exposed to UVR was investigated systematically to identify the existing hazard potential. Results: It should be noted that the permissible workplace exposure limits for UV emissions significantly exceeded after a few seconds. One critical value was strongly exceeded by a factor of 770. Conclusion: The prevention of emissions must first and foremost be carried out by structural measures. Furthermore, unambiguous protocols have to be defined and compliance must be monitored. For short-term activities in the hazard area, measures for the protection of eyes and skin must be taken.

• Environmental Analysis Health and Toxicology
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• v.18 no.2
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• pp.137-143
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• 2003

To validate and to estimate the chemical hazard playa very important role to environment and human health. The detection of many synthetic chemicals used in industry that may pose a genetic hazard in our environment is of great concern at present. Since these substances are not limited to the original products, and enter the environment, they have become widespread environmental pollutants, thus leading to a variety of chemicals that possibly threaten the public health. In this resepct, the clastogenicity of 8 synthetic chemicals was evaluated with bone marrow micronucleus assay in mice. The positive control, mitomycin C(2mg/kg,i.p.) revealed significant induction ratio of percentage of micronucleated polychromatic erythrocytes/l,000 polychromatic erythrocytes compared to carboxymethylcellulose control. The chemicals with relatively high LD$\_$50/ value such as phenylisocyanate (CAS No. 103-71-9), m-aminochlorobenzene (CAS No. 108-42-9) and 2-chloro-4-nitroaniline (CAS No. 121-87-9) revealed no significant induction of micronucleated polychromatic erythrocytes in mice. From this results, 8 synthetic chemicals widely used in industry have revealed no significant micronucleus induction of clastogenicity in mice in this experiment.

• Environmental Mutagens and Carcinogens
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• v.22 no.4
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• pp.215-222
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• 2002

The detection of many synthetic chemicals used in industry that may pose a genetic hazard in our environment is of great concern at present. Since these substances are not limited to the original products, and enter the environment, they have become widespread environmental pollutants, thus leading to a variety of chemicals that possibly threaten the public health. In this respect, to regulate and to evaluate the chemical hazard will be important to environment and human health. The clastogenicity of 17 synthetic chemicals was evaluated in Chinese hamster lung fibroblast cells in vitro. Two most cytotoxic chemicals, dodecyl methacrylate (CAS No. 142-90-5) and 2-ethylhexyl methacrylate (CAS No. 688-84-6), among 17 chemicals tested revealed no clastogenicity in the range of 0.0165-0.066 $\mu\textrm{g}$/$m\ell$ and 0.006-0.024 $\mu\textrm{g}$/$m\ell$ both in the presence and absence of metabolic activation system, respectively. All 17 chemicals revealed no significant induction of chromosomal aberration both in the presence and absence of metabolic activation system in this assay. From the results of chromosomal aberration assay with 17 synthetic chemicals in Chinese hamster lung cells in vitro, we did not observed positive clastogenic results in this study.

• Analytical Science and Technology
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• v.26 no.1
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• pp.73-79
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• 2013

The allyl isothiocyanate, capsaicin and dihydrocapsaicin as main components in self defense sprays were determined by gas chromatography-mass spectrometer (GC-MS). Although self defense spray was used to protect by myself, a social problem could be caused by the hazard of spray chemical due to use pungent liquid. To identify this, the pH of pungent liquid solutions, solubility to detergents, the existence of other materials and the types and amounts of pungent material in spray chemicals were investigated in this work. Finally, the amounts of allyl isothiocyanate, capsaicin and dihydrocapsaicin as pungent materials in them were determined by GC-MS. The pH of chemicals were about 5.7 as weak acid, the detergents can emulsify them with water well. And they did not contain fluorescent materials and hazard organic solvents. The pungent components in three real samples were only allyl isothiocyanate [47,600 mg/kg (47.6%)] in one sample, and mixtures with capsaicin [228 mg/kg~368 mg/kg (1.14%~1.84%)] and dihydrocapsaicin [224 mg/kg~414 mg/kg (1.12%~2.07%)] in the others, respectively.

• Journal of the Korean Society of Hazard Mitigation
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• v.5 no.1 s.16
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• pp.13-21
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• 2005

Experiments on settling behaviour of fine-grained particles without destroying the large fragile aggregates were carried out in still water with a CCD (Charged Coupled Device)-Camera. The experiments dealt with the measuring of the vertical concentration profile of cohesive particles with a CCD-Camera and the physico-chemical influences (NaCl, density, temperature and pH value) on the vertical distribution of the concentration. The vertical concentration profile of fine suspended particles (alumina and quartz) was possible up to $20,000\;mg/{\ell}$ with a CCD-Camera. The vertical concentration profile of cohesive sediments was on the decrease because of the increasing initial concentration, temperature and salinity. The vertical concentration profile of alumina was on the decrease quicker than quartz with increasing salinity. Furthermore, the pH value affects the settling behaviour of alumina. At a PH value of 4.2 the settling rate of the particles was very low and on the increase until pH 8.9 because of the aggregation behaviour of particles. From the PH value of 9 the average settling velocity was on the decrease.

• Journal of the Korean Society of Hazard Mitigation
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• v.3 no.4 s.11
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• pp.119-129
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• 2003

Concrete and steel are essential structural materials in the construction. But, concrete, different from steel, consists of many materials and is affected by many factors such as properties of materials, site environmental situations, and skill of constructors. Concrete have two kinds of properties, immediately knowing properties such as slump, air contents and time dependent one like strength. Therefore, concrete mixes depend on experiences of experts. However, at point of time using High Performance Concrete, new method is wanted because of more ingredients like mineral and chemical admixtures and lack of data. Artificial Neural Networks(ANN) are a mimic models of human brain to solve a complex nonlinear problem. They are powerful pattern recognizers and classifiers, also their computing abilities have been proven in the fields of prediction, estimation and pattern recognition. Here, among them, the back propagation network and radial basis function network ate used. Compositions of high-performance concrete mixes are eight components(water, cement, fine aggregate, coarse aggregate, fly ash, silica fume, superplasticizer and air-entrainer). Compressive strength, slump, and air contents are measured. The results show that neural networks are proper tools to minimize the uncertainties of the design of concrete mixtures.