• 한국화재소방학회논문지
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• 제31권2호
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• pp.17-23
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• 2017

소방용 특수방화복의 열보호 성능 평가를 위해 대류와 복사 열원을 이용한 시험방법을 비교하였다. 특히 특수방화복을 구성하는 겉감, 중간층, 안감이 각각 열보호 성능에 미치는 영향을 대류와 복사 열원에 대해 비교하였다. 대류 열원에 대한 열보호 성능시험은 KS K ISO 9151, 복사 열원에 대한 시험은 KS K ISO 6942 그리고 대류와 복사열원을 함께 사용하는 시험은 KS K ISO 17492의 방법에 따라 수행하였다. 같은 입사 열유속 조건($80kW/m^2$)에서 시험했을 때 대류 열원에 비해 복사 열원에 대한 열전달지수($t_{12}$, $t_{24}$) 값이 보다 크게 나왔다. 이는 대류에 비해 복사에 의한 영향이 느리게 나타났음을 의미한다. 대류 열원에 대해서는 안감이 열보호 성능에 가장 크게 영향을 미쳤고 이어서 중간층, 겉감 순서였다. 그러나 복사 열원에 대해서는 안감, 겉감, 중간층 순서로 열보호 성능에 미치는 영향이 컸다. 대류와 복사는 열전달 메카니즘이 근본적으로 다르며, 열원이 달라지면 재질 구성에 따라 열보호 성능 결과가 다르게 나올 수 있다. 따라서 특수방화복의 열보호 성능을 평가하기 위해서는 대류 열원 뿐만 아니라 복사 열원에 대한 시험도 중요함을 확인하였다.

• 한국화재소방학회논문지
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• 제28권4호
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• pp.97-103
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• 2014

소방보호복은 고열유속에 의한 화상방지를 위해 3층 이상의 복합소재로 구성되어 있으며, 각 소재 사이는 공기 간극이 존재한다. 화재에 의한 고열유속 노출 시 공기 간극 내에서의 열전달은 대류와 복사에 의해 주로 발생하며, 그로 인해 간극의 크기에 따라서 비선형 특징의 열 저항 크기를 갖게 된다. 그러므로 본 연구에서는 보호복 소재 사이의 여러 가지 공기 간극(0~7 mm)에 대한 보호복의 열 보호성능을 자세히 파악하기 위한 실험을 수행하였다. 복사 열 유속 입사시에 시간에 따른 각 소재의 온도 변화뿐만 아니라, 열 보호성능을 가장 효과적으로 나타낼 수 있는 지표(Radiant Protective Performance, RPP) 값의 공기간극에 대한 변화 특성을 파악하였다. 공기간극이 증가할수록 단열효과가 커짐으로 인해 후면의 온도는 낮아지고, RPP는 커짐을 확인할 수 있었다. 특히 일정 열유속 조건에서 공기간극에 대한 RPP 값은 선형적인 특성을 나타내었고, 그러한 결과를 바탕으로 다양한 입사 열유속 및 공기 간극 조건에 대해 비교적 간단한 형태의 RPP 지표 예측 식을 제안하였고, 좋은 예측 결과를 얻을 수 있었다.

• 한국수소및신에너지학회논문집
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• 제35권3호
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• pp.310-317
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• 2024

In this study, Aimed to develop technology to ensure the safety of firefighters responding to hydrogen incidents and to review the performance of protective super absorbent polymer (SAP) that could help maintain the thermal protection performance of equipment with protective properties. Tests were conducted, including bench-scale and full-scale thermal exposure tests, to review the protective performance of SAP using firefighting garments commonly used by firefighters. The results showed that without SAP application, 2nd degree burn areas were measured at 9.4%, and 3rd degree burn areas at 7.7%. In contrast, when SAP was applied, the percentage of 2nd degree burn areas decreased to 7% on the lower body, and there was no temperature rise causing 3rd degree burns. Therefore, it is expected that by applying SAP to the outer surface of firefighter garments, even under temporarily high temperature conditions such as hydrogen jet flames, thermal damage to firefighters could be protected for a certain period.

• 한국화재소방학회논문지
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• 제28권2호
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• pp.1-8
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• 2014

보호복 섬유 및 재료의 개발을 통해 나아진 단열 성능을 제공함에도 불구하고 보호복의 화상 방지는 아직도 중요한 사항이다. 화염으로부터의 보호성능을 보장받기 위해서 보호복의 정확한 성능검증이 필요하며, 열보호 특성을 정확히 파악하기 위해 ISO 등은 시험방법을 표준화하여 제시하고 있다. 하지만 대부분의 경우, 높은 열유속 조건에 대해 보호복의 열보호 성능을 시험하는 것으로 되어 있어, 고열유속에 의한 시편의 파괴가 일어나기 쉽다. 그러므로 낮은 열유속 조건에서 보호복의 열보호 성능을 측정하는 방법이 필요하며, 본 연구에서는 낮은 열유속에 대한 열보호 성능을 측정할 수 있는 화상 및 통증유발시간에 기초한 개선된 RPP(복사열 보호 성능) 지수와 그의 측정방법을 제안하였다. 또한 제안된 열보호성능 측정 방법을 실험을 통해 확인하고, 보호복의 비정상열전달특성을 파악하였다. 또한 기존의 여러 가지 열보호성능지표들과 제안지표와의 관계를 제시하였다.

• Safety and Health at Work
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• 제15권2호
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• pp.228-235
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• 2024

Background: Glove reuse poses risks, as chemicals can persist even after cleaning. Decontamination methods like thermal aeration, recommended by US OSHA, vary in effectiveness. Some studies show promising results, while others emphasize the importance of considering both permeation and tensile strength changes. This research advocates for informed glove reuse, emphasizing optimal thermal aeration temperatures and providing evidence to guide users in maintaining protection efficiency. Methods: The investigation evaluated Neoprene and Nitrile gloves (22 mils). Permeation tests with toluene and acetone adhered to American Society for Testing Materials (ASTM) F739 standards. Decontamination optimization involved aeration at various temperatures. The experiment proceeded with a maximum of 22 re-exposure cycles. Tensile strength and elongation were assessed following ASTM D 412 protocols. Breakthrough time differences were statistically analyzed using t-test and ANOVA. Results: At room temperature, glove residuals decreased, and standardized breakthrough time (SBT)₂ was significantly lower than SBT₁, indicating reduced protection. Higher temperature decontamination accelerated residual removal, with ∆SBT (SBT₂/SBT₁) exceeding 100%, signifying restored protection. Tensile tests showed stable neoprene properties postdecontamination. Results underscore thermal aeration's efficacy for gloves reuse, emphasizing temperature's pivotal role. Findings recommend meticulous management strategies, especially post-breakthrough, to uphold glove-protective performance. Conclusions: Thermal aeration at 100℃ for 1 hour proves effective, restoring protection without compromising glove strength. The study, covering twenty cycles, suggests safe glove reuse with proper decontamination, reducing costs significantly. However, limitations in chemical-glove combinations and exclusive focus on specific gloves caution against broad generalization. The absence of regulatory directives on glove reuse highlight the importance of informed selection and rigorous decontamination validation for workplace safety practices.

• 한국환경복원기술학회지
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• 제21권1호
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• pp.133-143
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• 2018

In spite of the growing importance of landscaping trees, the rate of flawed and withered trees damaged by pest, disease, drought or frost is increasing. In order to evaluate the performance of the Tree Protective Pad, which are developed to reduce the failure ratio in landscape planting, the tree protective pad for 'digging', 'pest controlling', and 'insulating' are tested based on the five functional criteria; moisturizing effect, wither preventive effect, pest and disease control, thermal effect, tensile strength, and environmental performance. The result of this study is as follows. The moisturizing effect of the tree protective pad for digging is found to be outstanding. According to the result of testing the pad on trees, in particular, it is better than jute tape in wither preventive effect, which means it is expected to prevent flaw and wilt from planting during the improper seasons like summertime. The experiment of installing the protective tree pad for pest controlling to the trunk of Quercus mongolica shows that preventive effect of the pad from diseases and insects is superior, and it also has economical effect by reducing the use of agricultural chemicals. The comparative test of the pad for insulating and jute tape proves that the temperature of the pad is about $2^{\circ}C$ higher than outside. The rate of tensile strength and biodegradation of the pad exceeds the optimal level, so it is revealed that the pad may be the work efficient and environment-friendly product. Likewise, by timely irrigating trees, the tree protective pad economically prevents trees from pest, disease,drought or frost, which may be caused by improper seasonal or delayed planting. As a means of reducing the flaw and facilitating the growth of trees, the exceptional performance of the pad is expected to effectively used in landscape planting and management.

• 한국염색가공학회지
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• 제30권4호
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• pp.227-236
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• 2018

As consciousness of safety becomes an important social issue, the demand for protective clothing is increasing. Conventional flame-retardant cotton working wear has low durability, and working wear with m-aramid fibers are stiff, heavy, less permeable, and expensive. In this study, recycled m-aramid and cotton have been blended to produce woven fabric of different compositions to enhance high performance and comfort to solve aforementioned problems. The fabrics were analyzed according to constituents and various structural factors. Mechanical properties were measured using KES-FB system. The measured thermal properties are TGA, $Q_{max}$, TPP and RPP. Fabric with polyurethane yarn covered by m-aramid/cotton spun yarn is observed to have good wearability. The fabric of open end spun yarn showed more stiffness than that of ring spun yarn. The sample with the high count of yarn has more smooth surface. In addition, high m-aramid content fabric is considered to have relatively high stiffness when using as clothing. In TGA the fabric with higher m-aramid content showed more stable decomposition behavior. The fabric having rough surface showed lower heat transfer properties in $Q_{max}$. The influence of the fabric thickness was important in convection and radiant heat test.

• 대한토목학회논문집
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• 제42권5호
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• pp.671-679
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• 2022

국내 탄약 시험장과 군의 포탄 사격 훈련장은 잦은 사격과 폭발 실험으로 인해 충격파와 파편 등의 유해인자가 발생한다. 이에 따라 지역 주민의 민원이 급증하고 있으며 근접한 시설물과 인명피해의 위험이 크다. 최근 건설된 탄약 시험장은 부지확보 제한에 따라 반경 300 m 이내의 좁은 지역에서 화포 사격 및 로켓 추진기관 연소시험 시설을 구축하였으나 적절한 방호구조물이 없어 시설물 피해가 누적되고 있다. 따라서 본 연구에서는 화포 사격 및 로켓추진기관 실험 간 발생하는 소음, 진동, 충격파, 열 효과 등 유해인자에 대한 정량적 데이터를 측정하고 폭발 압력 특성을 분석하여 탄약 시험장의 강재 방호구조물 적용 연구를 수행하였다.

• Journal of Biosystems Engineering
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• 제39권1호
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• pp.21-33
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• 2014

Background: Significant technological development and changes happened in the tractor industries. Contrariwise, the test procedures of the major standard development organizations (SDO's) remained unchanged or with a little modification over the years, demanding new tractor test standards or improvement of existing ones for tractor performance, safety, and comfort. Purpose: This study focuses on reviewing the research trends regarding performance, safety and comfort evaluation of agricultural tractors. Based on this review, few recommendations were proposed to revise or improve the current test standards. Review: Tractor power take-off power test using the DC electric dynamometer reduced human error in the testing process and increased the accuracy of the test results. GPS signals were used to determine acceleration and converted into torque. High capacity double extended octagonal ring dynamometer has been designed to measure drawbar forces. Numerical optimization methodology has been used to design three-point hitch. Numerous technologies, driving strategies, and transmission characteristics are being considered for reducing emissions of gaseous and particulate pollutants. Engine emission control technology standards need to be revised to meet the exhaust regulations for agricultural tractors. Finite Element Analysis (FEA) program has been used to design Roll-Over Protective Structures (ROPS). Program and methodology has been presented for testing tractor brake systems. Whole-body vibration emission levels have been found to be very dependent upon the nature of field operation performed, and the test track techniques required development/adaptation to improve their suitability during standardized assessment. Emphasizes should be given to improve visibility and thermal environment inside the cab for tractor operator. Tractors need to be evaluated under electromagnetic compatibility test conditions due to large growing of electronic devices. Research trends reviewed in this paper can be considered for possible revision or improvement of tractor performance, safety, and comfort test standards.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.59-60
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• 2014

To prevent the rusting of steel, a variety of finishing materials has been applied. When steel is exposed to an extreme chloride environment, however, the thermal performance and aging of the finishing materials cause the material to lose its rust protective performance. In this study, an accelerated corrosion test was performed on five different finishing materials for steel, to determine the critical values of corrosion. As the result, the critical value of corrosion was found with no coat between 0.58mg/d㎡ and 0.73mg/d㎡, with urethane coat between 7.89mg/d㎡~8.46mg/d㎡, with one-layered red lead coat between 57.95mg/d㎡ and 69.48mg/d㎡, and with staleness201 between 80.73mg/d㎡ and 89.35mg/d㎡.