Chang-Hoon Bang

Numerical Study on Skin Burn Injury due to Flash Flame Exposure

Many fire-fighters suffer from the burn injuries, and the severe burns are the most catastrophic injury a person can survive, resulting in pain, emotional stress, and tremendous economic costs. It is important to understand the physiology of burns for prevention from skin burns and a successful treatment of a burn patient. But a few researches have been presented because the complex physical phenomena of our inside body like non-linearity characteristics of human skin make them difficult. Thus in this study, thermal analyses of biological tissues exposed to a flash fire causing severe tissue damage were studied by using a finite difference method based on the Pennes bio-heat equation. The several previous models for skin thermo-physical properties were summarized, and the calculated values with those models of tissue injury were compared with the results obtained by the previous experiment for low heat flux conditions. The skin models with good agreement could be found. Also, the skin burn injury prediction results with the best model for high heat flux conditions by flash flame were suggested.

Physiological Changes According to Workload Wearing Aluminized Firefighter's Protective Clothing

본 연구에서는 소방방열복 착용시 작업강도가 신체에 미치는 영향을 조사하여 소방공무원의 안전을 위한 기초자료 제공을 목적으로 하며 연구에서 얻어진 결과를 제시하면 다음과 같다. 작업종료시(20분)에 작업강도가 4 METs에서 8METs로 증가함에 따라 평균피부온도차(33.3 %), 고막온도차(57.1 %), 심박수(32.5 %), 운동자각도(75.6 %) 등은 통계적으로 유의하게 높게 나타났으며, 온냉감과 체중감소는 유의한 차이가 나타나지 않았다. 이상의 결과 소방방열복 착용시 작업강도의 증가는 신체에 많은 영향을 미치는 것으로 판단된다.ABSTRACTThe aim of study intends to investigate physiological changes according to workload wearing aluminized firefighter’sprotective clothing and to provide the base data for the safety of firefighter. The results of the study are as follows. Toincrease work intensity 4 to 8 METs after experiment (20 min), mean skin temperature change (33.3 %), tympanic tem-perature change (57.1 %) heart rate (32.5 %), RPE (75.6 %) is statistically significantly higher and thermal Sensation,weight loss are not statistically significant. It was concluded that physiological changes of human body varied consider-ably by increase of workload wearing aluminized firefighter’s protective clothing.

Changes of oxidative/antioxidative parameters and DNA damage in firefighters wearing personal protective equipment during treadmill walking training

[Purpose] The purpose of this study was to investigate the influence of personal protective equipment on the oxidant/antioxidant parameters and DNA damage in firefighters during training and recovery. [Subjects and Methods] Twelve male nonsmoking volunteer firefighters (35.1 ± 7.2 years) underwent two maximal treadmill training (9 METs, 6 km/h), within 2 weeks, one in regular clothes and one in personal protective equipment weighing 22.1 kg. Blood samples were obtained before, right after, and 40 min after training. Plasma conjugated dienes, total radical trapping antioxidant potential, erythrocytes antioxidant enzymes activities, and leukocyte DNA damage were measured. [Results] Wearing personal protective equipment during treadmill walking training resulted in increases of plasma conjugated dienes, total radical trapping antioxidant potential, and leukocyte DNA resistance to oxidative stress, which were recovered after in 40 min of rest. Erythrocyte antioxidant enzymes activities remained unchanged during the training either with regular clothes or personal protective equipment. [Conclusion] These results suggest that wearing personal protective equipment during firefighting work could induce oxidative stress, which was enough to produce DNA damage in leukocytes.

Compressive Behavior and Mechanical Characteristics and Their Application to Stress-Strain Relationship of Steel Fiber-Reinforced Reactive Powder Concrete

Although mechanical properties of concrete under uniaxial compression are important to design concrete structure, current design codes or other empirical equations have clear limitation on the prediction of mechanical properties. Various types of fiber-reinforced reactive powder concrete matrix were tested for making more usable and accurate estimation equations for mechanical properties for ultra high strength concrete. Investigated matrix has compressive strength ranged from 30 MPa to 200 MPa. Ultra high strength concrete was made by means of reactive powder concrete. Preventing brittle failure of this type of matrix, steel fibers were used. The volume fraction of steel fiber ranged from 0 to 2%. From the test results, steel fibers significantly increase the ductility, strength and stiffness of ultra high strength matrix. They are quantified with previously conducted researches about material properties of concrete under uniaxial loading. Applicability of estimation equations for mechanical properties of concrete was evaluated with test results of this study. From the evaluation, regression analysis was carried out, and new estimation equations were proposed. And these proposed equations were applied into stress-strain relation which was developed by previous research. Ascending part, which was affected by proposed equations of this study directly, well fitted into experimental results.

Study on the Thermal Protective Performance Measurements of Fire Fighter`s Protective Clothing for Low Level Radiant Heat Exposures

Despite advancements in the development of synthetic fibers and materials that provide better insulation, fire burn injuries remain a significant issue. To ensure adequate protection, clothing and equipment must be selected on the basis of performance. There are different standards like ISO standards applicable to each of the various types of clothing used by fire fighters. But, in most cases, the tests are performed in the conditions of high heat flux exposure, the clothing material can be destroyed easily. Thus the effective way to investigate the protective performance for the low (radiant) heat flux conditions should be needed. Therefore improved RPP (Radiant Protective Performance) test method based on the onset of pain burn injury was suggested. Experiments were performed to verify the proposed method with current protective clothing for fire fighters and the transient heat transfer characteristics were identified, also. Moreover, several protective performance indices were acquired from experimental results to analyze their relations.

Effect of Wearing Fire Leather Boot For Physical Balance

Abstract The aim of study intends to investigate effect of weight of fire leather boot for physical balance and to provide the base data forthe safety of firefighter. The results of the study are as follows. Static balance tests with closed-eyes foot balance, opened-eyesfoot balance on cushion and dynamic balance tests with beam walking, closed-eyes walking at 10 m, barefoot group and fireleather boot group is not statistically significant. For balance comparisons between firefighting and rescue & EMS was not sta-tistically significant between barefoot and fire leather boot. For balance checks about career, closed-eyes foot balance is appearedstatistically significant between career groups and the rest of the test results are not statistically significant.Key words : Physical balance, Fire leather boot 요지 본 연구에서는 소방용 가죽제안전화 착용이 신체평형성에 미치는 영향을 조사하여 소방공무원의 안전을 위한 기초자료 제공을 목적으로 하며 연구에서 얻어진 결과를 제시하면 다음과 같다. 정적평형성 검사를 위한 눈감고 한발서기와 쿠션 위에 서기와 동적평형성 검사인 평균대 걷기와 눈감고 10 m 걷기에서 맨발과 소방용 가죽제안전화 착용간의 통계적 유의함은 나타나지않았다. 화재진압과 구조구급을 담당하는 집단간의 평형성비교에서 맨발과 소방용 가죽제안전화 착용간의 통계적 유의함은 나타나지 않았다. 근무경력에 따른 소방공무원의 평형성 검사 결과 눈감고 한발서기에서 맨발의 경우 경력간의 통계적의 유의함이나타났으며, 나머지 검사에서는 통계적으로 유의하지 않았다.핵심용어 : 신체평형성, 소방용 가죽제 안전화 ······························································································································· ···································································································

A Study on the Physiological Response Wearing Fire Chemical Protective Clothing

현재 우리나라의 생활수준 향상에 따라 새로운 용도와 성분의 화학물질이 끊임없이 개발 생산되고 있으며 우리의 일상생활과 경제발전에 큰 도움을 준다. 하지만 화학사고가 발생하게되면 화학물질은 우리에게 큰 위험요인으로 작용하게 된다.화학물질은 기체, 액체, 고체 등 3상의 형태로 존재하고 사용한계를 벗어난 누출, 화재, 폭발 등의 사고시 위해성은 매우치명적이다. 또한 화학사고는 피해규모가 크고, 화학물질의종류에 따라 피해반경이 넓어진다는 특성과 다른 사고에 비해 인체에 미치는 영향요인이 오랜 기간에 걸쳐 다양하게 나타나는 특성이 있다.환경부에서 4년 주기로 이루어지는 화학물질유통량 조사결과를 보면 2010년 우리나라의 화학물질 유통량은 432.5백만톤 이었고, 화학물질을 취급하는 업체는 16,547개였다. 이 업체들은 울산, 여수, 온산, 시화 등 대규모 산업단지에 1,000여개업체가 있고, 나머지 15,500여개 업체는 기타 중소형 산업단지에 흩어져 있다. 따라서 화학물질을 취급하는 업체는 전국 어디에나 있으며, 화학물질의 사고 역시 전국 어디에서나일어날 가능성이 있다(MOE, 2011).화학물질 사고는 대부분 화학물질의 누출, 화재, 폭발로 발생되며 이는 발생지역의 주민들에게 엄청난 인적·물적 피해Abstract

A Change of Body Temperature and Inflammatory Markers Wearing Fire Fighting Equipment

This aim of this study is to examine the change of body temperature(tympanic and mean skin temperature) and inflammatory marks (CRP, TNF-) wearing fire fighting equipment in high temperature and to provide the basic date for the safety of fire fighters. The results of the study are as follows; Tympanic and mean skin temperature showed significant difference in main effect of time. Also, CRP and TNF- showed significant difference in main effect of time. On the base of the results of the current study, wearing fire fighting equipment in high temperature environment was shown to affect body temperature and inflammatory markers. Further research on physiological variables during various fire-fighting tasks should also be carried out.

A Study on Body Balance of Firefighter Wearing Fire Protective Equipments

The aim of study intends to investigate a study on body balance of firefighter wearing fire protective equipments and to provide the basic data for the safety of firefighter. The results of the study are as follows; Static balance tests with closed-eyes foot balance, firefighter protective clothing(Group A), firefighter protective clothing and Self-contained breathing apparatus(Group B), firefighter protective clothing, Self-contained breathing apparatus and 10 kg jacket(Group C), among three groups were statistically significant and in other tests, the difference was not statistically significant. The balance comparisons between firefighting and rescue & EMS was not statistically significant among three groups. For balance checks about career, closed-eyes foot balance with the heaviest Group C is appeared statistically significant and the results of the rest test are not statistically significant.

Physical Response of Human Body Wearing Self Contained Breathing Apparatus

The aim of study intends to investigate physical response of human body wearing Self Contained Breathing Apparatus and to provide the base data for the safety of firefighter. The results of the study are as follows. when wearing SCBA, the mean skin temperature (7 %), heart rate (28 %), rate of perceived exertion (65.4 %), metabolic equivalents (70.7 %) were significantly higher (p