• Title/Summary/Keyword: safety rate

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Evaluation of Fire Characteristics for Particle-board with Exfoliated Graphite Nanoplatelets Added (탄소재료의 적용 방법에 따른 파티클 보드의 연소 특성)

  • Seo, Hyun Jeong;Jo, Jeong Min;Hwang, Wuk;Lee, Min Chul
    • Journal of the Korean Society of Combustion
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    • v.22 no.4
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    • pp.1-8
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    • 2017
  • This study was conducted to evaluate the fire retardant performance of exfoliated graphite nanoplatelets (xGnP) applied for particleboard. This work measured heat release rate(HRR), total heat release(THR) and smoke production rate(SPR) of xGnP added particleboard, using cone calorimeter to assess its fire characteristics according to the KS F ISO 5660-1 standard code. Heat release rates of all specimens treated by xGnP were less than the $200kW/m^2$ for a total experiment period of five minutes. Heat release rates of the specimens coated with xGnP were lower than those of the specimens made by mixing wood particles with xGnP directly. Meanwhile, the total heat release rates of xGnP coated specimen maintained quite lower level than the uncoated so the xGnP coating were effective in improving the fire retardant performance of particleboard. However, the smoke emission peaking problem at the initial combustion period, which was caused by adding base coating materials, should be resolved for further satisfaction as a fire retardant materials.

An Experimental Investigation on Fire Characteristics of Light Oil & Methanol for Spilled Surface (경유와 메탄올의 유출표면에 따른 화재특성에 관한 실험적 고찰)

  • Lee, Jung-Yon;Jung, Ki-Chang;Kim, Hong
    • Journal of the Korean Society of Safety
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    • v.25 no.6
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    • pp.103-108
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    • 2010
  • In this study, tank truck incidents of road transport of hazardous materials to experimental investigated the potential fire hazard. Real scale fire was to perform experiments for on this qualitative and quantitative data collection and analysis. Particularly affected by radiant heat from the flames caused and damage estimates range investigated accordingly. Flame temperature, internal temperature of tank and emitted radiation from the flames was investigated. The flame of light oil spill caused a fire at a temperature of about $300^{\circ}C$ high in comparison with the methanol by combustion of diesel and methanol, according to the difference, the flame duration changes varies depending on the Burning rate, amount of radiant heat flux from light oil fire was 4 times increases compared with fire of methanol. Depending on spill locations(kinds of road surfaces, absorbing rate) and the longer the duration of the flame important factors for the internal temperature of tank truck rise was found. Dirt roads than paved road accident in a fire caused by leakage of hazardous was could the higher the damaged. Therefor, Fire suppression activities should be required in particular to be around.

A Study on the Optimal Installation Technology of LPG Storage Tank through Taguchi Method (다구찌 기법을 통한 LPG 저장탱크시공방법의 최적화에 관한 연구)

  • Leem, Sa-Hwan;Huh, Yong-Jeong;Paek, Seung-Cheol;Lee, Jong-Rark
    • Journal of the Korean Society of Safety
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    • v.25 no.6
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    • pp.98-102
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    • 2010
  • LPG (Liquefied Petroleum Gas) vehicles in metropolitan area are being applied to improve air quality and have been proven effective for the reduction of air pollutant. In addition, the demand of gas as an eco-friendly energy source has being increased. With the LPG filling station is also increasing every year. These gas stations are required to install the securest storage tank because of possibility of causing huge loss of life and property. Therefore, in this paper, underground containment type is proposed as installation of the LPG storage tank using Taguchi method, which is considered to be more safe, economical, efficient, easy checking and simple construction method than any other. If leakage, economics, real estate utilization rate, safety, easy to check, simple construct about above ground, buried underground and underground containment storage tank are analyzed by Taguchi method, real estate utilization rate, economic and safety in turn are improved. Therefore, the underground containment storage tank is a optimal installation technology.

An Experimental Study on Decrease of Noise for Air Nozzle (에어노즐의 소음저감 대책에 관한 연구)

  • Jeon, Seoung-Tae;Kim, Jong-Hyun;Lee, Keun-Oh
    • Journal of the Korean Society of Safety
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    • v.18 no.4
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    • pp.51-56
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    • 2003
  • The goal of this study is to show the way to decrease the noise from air nozzles. The variables of this test are the shapes of air nozzles, air flow rate and the distance between a reflection plate and a nozzle tip. This experiment is aimed to find the most appropriate condition to minimize the noise. These are the results. If diameter ratio is more than 12:8, noise level increases by over 10 dB(A) regradless of the distance between a reflection plate and a nozzle and the existence of a reflection plate. And when $L_2$ of a nozzle is 5mm long, noise level rise relatively highly. So, it is strongly recommended that $L_2$ should be manufactured more than 10mm. The reason for a high intensity noise is that when diameter ratio is more than 12:8, the diameter of a nozzle tip($D_2$) turns small drastically, which increases the air velocity. It is assumed that when the vortes is great around the spots where a nozzle hole is suddenly smaller, great turbulent flow increases much noise.

A Study on the Safety Management Items for Preventing Accidents of Aged Construction Workers (중.고령 건설근로자의 재해예방을 위한 안전관리 항목에 관한 연구)

  • Lee, Hyun-Chul;Song, Do-Heom;Go, Seong-Seok
    • Journal of the Korean Society of Safety
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    • v.24 no.1
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    • pp.50-59
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    • 2009
  • Korea reached an aging society in 2000, and it is progressed quickly now. Government forecasts that the number of aged people over 65 years old will increase from 7.2%(2000) to above 14.3% among total population in 2018. Workers over fifty years old are increasing in construction field every year. These aged workers are exposed to various construction accidents, and also their accident rate is very high because of physical and psychological changes by aging. Specially, a disaster of aged workers more than 50 years old is fronted at the serious situation in the construction industry which has variable working environment. Thus, the purpose of this study is to suggest the precaution by analysing disaster characteristics of aged construction workers. Also, this study aims to present a basic counter-plan according to important safety management list which is abstracted from the work, aged construction workers' accident rate is high.

A Study on the Safety and Management Plan of Aviation Maintenance due to Human Error (인적오류에 의한 항공정비의 안전과 관리방안에 관한 연구)

  • Park, Se-Jong;Jeon, Eon-Chan
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.19 no.10
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    • pp.68-73
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    • 2020
  • The proportion of airline accidents caused by human factors is steadily increasing. The aviation industry has made considerable progress in reducing the accident rate; however, since the early 1980s, the accident rate has remained constant. Due to airspace congestion, the safety margins of these existing safety promotion methods are gradually decreasing; thus, new methods to prevent accidents and quasi-accidents must be devised. Causative factors of aviation accidents include increased air traffic due to increased air demand, increased cumulative working hours due to long-distance flights, and complicated flight environments. Accidents often occur when several small errors accumulate in the normal course of operation, rather than after a single error. Accordingly, in this study, the impacts on air navigation due to human error by aviation maintenance personnel and varying international standards (i.e., KOCA vs. F.A.A vs. EASA) analyzed, and the relationship between human decision-making and behavior was investigated. The resulting safety analysis and alternatives were presented to prevent aviation maintenance accidents and cognitive ergonomics errors.

A Study on the Test Method of Autonomous Vehicle for Fixed Targets (고정목표에 대한 자율주행자동차 시험방법에 관한 연구)

  • Kim, Bong-Ju;Lee, Seon-Bong
    • Journal of Auto-vehicle Safety Association
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    • v.14 no.3
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    • pp.6-16
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    • 2022
  • Recent, the issue of the fourth industrial revolution triggered by technological advances has changed the automobile industry centered on internal combustion engines, and quantitative growth of the global automobile market, which has grown rapidly, has been slowing since 2015. These advances in technology are expected to develop beyond the advanced driver assistance system to autonomous driving technology. According to SAE-J3016 published by the Society of Automotive Engineers, the technology of autonomous vehicles is divided into a total of six stages according to the driver's intervention and automation level from 0 to 5. Securing safety for autonomous vehicles is important. But, research on safety evaluation theory and autonomous vehicle evaluation method based on real vehicle test is insufficient. In this study, the longitudinal distance theory equation and continuous test scenario were proposed for the test method of autonomous vehicles for fixed targets, and the real vehicle test was conducted. When comparing the theoretical values compared to the measured values, it was determined that it was reliable with a minimum error rate of 0.484% and a maximum error rate of 7.391%. Using the proposed theoretical equation, it is judged that it can be used as a safety evaluation method in an environment where real vehicle test is not possible because it can grasp the trend in the longitudinal direction in the development stage.

The Suggestions for the Minimization of Safety Accidents in the Primary Science Experiments (초등학교 과학 실험에서의 안전사고 최소화 방안)

  • Kwon, Chi-Soon;Choi, Eun-Sun
    • Journal of the Korean Society of Earth Science Education
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    • v.2 no.1
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    • pp.13-22
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    • 2009
  • This study examined the dangerous elements in primary science textbooks and had some suggestions for the minimization of safety accidents in the science class experiments. The research results are as follows: 1) The rate of accident in the primary science experiments was not high, but potential for the outbreak of safety accidents was always present. 2) it is necessary to include safety contents on science textbooks. The survey revealed that only 18 percent of safety education materials include on science textbooks. 3) It will be desirable for science experiment lessons to include safety education materials for safety experiments. This could also help the students develop the right recognition and attitude regarding safety. 4) There was lack of safety devices those were required to be kept at science labs. The survey showed that about 20 percent of the schools had the experimental clothing. 5) Safety training is often conducted in an overly simplified manner, and no special time is allocated to it. In conclusion, to improve the problems pertaining to school safety accident, courses on safety training are essential as textbooks and teachers. Constant and systematic instructions on safety should be done in order to prevent potential safety accidents.

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The Management Actual Condition and Recognition of Material Safety Data Sheets in Dental Laboratories (치과기공소에서의 물질안전보건자료(MSDS) 인식 및 관리 실태)

  • Bae, Eun-Jeong
    • Journal of Technologic Dentistry
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    • v.32 no.3
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    • pp.221-232
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    • 2010
  • Purpose: It is necessary for dental technicians exposed to hazardous chemicals in the dental laboratories to be informed of the various harmful effects of chemicals for their health and safety. The purposes of this study was to investigate the actual condition of the use of MSDS in dental laboratories and the recognition rate of MSDS for dental technicians. Methods: 231 dental technicians who were self-written questionnaire. The results were analyzed by SPSS 12.0. The answers to the questionnaire underwent frequency analysis, chi-square test and correlation analysis were performed to investigate association between health effects and recognition rate of chemical information. Results: The results from the effects of damage caused by chemicals 60.7%, and when it was less than 2 years working experience 47.6%. Currently any dental laboratories(rooms) was not furnished MSDS(0%) and even similar data furnishing rate was only 17.3%. Answer rate of 'Do not know about MSDS' was 73.6%. In addition to, education in the types and characteristics of chemicals(74.5%) does not receive all the higher education. For the question of 'To prevent human risks and accidents, is to provide chemical information needed', the answer rate of 'needed' was 87.2%. Moreover, the answer rate of 'To provide chemical information that could prevent accidents' was 76.6%. Therefore it was found that dental technicians need to be provided for chemical information. In addition, they wanted to get education related to chemicals used in the workplace(80.5%), and 90.9% was answered that they was willing to keep MSDS in they workplace. Conclusion: This study investigated the current dental laboratories(rooms) and the MSDS for the awareness and recognition of workers was very low, education was not being conducted properly. The dental laboratories(rooms) of the compact characteristics of the MSDS was not reasonably accessible and the furnishing location, dental laboratories(rooms) for the real item was needed for improvement. MSDS for dental technicians through education and promotion of information about chemicals and chemicals was to prevent health problems caused by the MSDS that will raise awareness of the necessity.

Computation of Nonpremixed Methane-Air Flames in Microgravity II. Radius and Thickness of Flame (무중력에서의 비예혼합 메탄-공기 화염의 전산 II. 화염의 반경과 두께)

  • Park Woe-Chul
    • Journal of the Korean Society of Safety
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    • v.19 no.3 s.67
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    • pp.124-129
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    • 2004
  • To evaluate the numerical method in simulation of diffusion flames and to see the effects of strain rate and fuel concentration on the flame radius and thickness, the nonpremixed methane-air counterflow flames in microgravity were simulated axisymmetrically by using the MST Fire Dynamics Simulator (FDS). The $1000^{\circ}C$ based flame radius and thickness were investigated for the mole fraction of methane in the fuel stream, $X_m=20,\;50,\;and\;80\%$ and the global strain rates $a_g=20,\;60,\;and\;90s^{-1}$ for each mole fraction. The flame radius increased with the global strain rate while the flame thickness decreased linearly as the global strain rate increased. The flame radius decreased as the mole fraction increased, but it was not so sensitive to the mole fraction compared with the global strain rate. Since there was good agreement in the nondimensional flame thickness obtained with OPPDIF and FDS respectively, it was confirmed that FDS is capable of predicting well the counterflow flames in a wide range of strain rate and fuel concentration.