• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2015.05a
• /
• pp.128-129
• /
• 2015

Domestic construction industry has seen a negative image in the sense that various accident occurs frequently. Status of construction accidents in the case of domestic workers is reduced. However, if the situation of foreign workers is increasing every year. This study aims to create high-temperature exposure standard table for foreign workers and domestic workers in the analysis through the discomfort index of fatalities and using the WBGT index for reducing fatalities foreign workers to improve the image of the construction industry.

• Tunnel and Underground Space
• /
• v.24 no.2
• /
• pp.166-175
• /
• 2014

In this study, the thermal environment in a large scale coal mine located in Taebaek, Gangwondo was assessed by a field survey. In order to estimate the thermal environment, various heat stress indices such as WBGT, HSI, ESI, KATA index and effective temperature were investigated. Correlation analysis was also conducted. It was found that the thermal environment in most workplace was high. In particular, the correlation coefficient between HSI reflected in physiological fatigue characteristic and the maximum sweat evaporation heat was -0.834. This shows that the correlation coefficient have the most influence on HSI index. The factor which has the most influence on the maximum sweat evaporation heat is velocity of air. The thermal environment of high-depth coal mines is likely to be improved by installing a structure that enables the maximum prevention of extended digging, air doors, or the leakage of the inflow of air in the first shaft.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.13 no.6
• /
• pp.39-48
• /
• 2010

The purpose of this study was to analyze air temperature decreasing effects by shading and ventilation at micro-scale experiment plots, especially focused on the Wet Bulb Globe Temperature (WBGT) in outdoor spaces. To monitor the time-serial changes of Dry-bulb Temperature (DT), Globe Temperature (GT) and Relative Humidity (RH) in the wind blocking and shading conditions, Two hexahedral steel frames were established on the open grass field, the dimension of each frame was 1.5m(W)${\times}$1.5m(L)${\times}$1.5m(H). Four vertical side of one frame was covered by transparent polyethylene film to prevent wind passing through (Wind break plot; WP). The top side of the other frame was covered with shading curtain which intercept 95% of solar light and energy (Shading plot; SP). And, Another vertical steel frame without any treatment preventing ventilation and sunlight was set up, which represents natural conditions (Control plot; CP). The major findings were as follows; 1. The average globe temperature (GT) was highest at WP showing $50.94^{\circ}C$ and lowest at SP showing $34.58^{\circ}C$. The GT of natural condition (SP) was $42.31^{\circ}C$ locating the midst between WP and SP. The difference of GT of each plot was about $8-16^{\circ}C$, which means the ventilation and shading has significant effect on decreasing the temperature. 2. WP showed the highest average dry-bulb temperature (DT) of $38.41^{\circ}C$ which apparently differ from SP and CP showing $31.94^{\circ}C$ and $33.15^{\circ}C$ respectively. The DT of SP and CP were nearly the same. 3. The average relative humidity (RH) was lowest at WP showing 15.21%, but SP and CP had similar RH 28.79%, 28.02% respectively. 4. The average of calculated WBGT were the highest at the WP ($27.61^{\circ}C$) and the lowest at the SP ($23.64^{\circ}C$). The CP ($25.49^{\circ}C$) was in the middle of the others. As summery, compared with natural condition (CP), the wind blocking increased about $2.11^{\circ}C$ WBGT, but the shading decreased about $1.84^{\circ}C$ WBGT. So It can be apparently said that the open space with much shading trees, sheltering furnitures and well-delivered wind corridor can reduce useless and even harmful energy for human outdoor activity considerably in outdoor spaces.

• Journal of Environmental Science International
• /
• v.26 no.12
• /
• pp.1363-1374
• /
• 2017

Global climate change caused by industrialization has caused abnormal weather conditions such as urban temperatures and tropical nights, urban heat waves, heat waves, and heavy rains. Therefore, the study tried to analyze climate conditions and weather conditions in the streets and analyze climate factors and meteorological factors that lead to inconvenience to citizens. In the case of trees, the overall temperature, surface temperature, solar irradiance, and net radiation were measured low, and the temperature was lower in the Pedestrian road than in roads. The dry bulb temperature, the black bulb temperature, and the wet bulb temperature for the thermal evaluation showed the same tendency. In the case of thermal evaluation, there was a similar tendency to temperature in WBGT, MRT, and UTCI, and varied differences between types. Although the correlation between the meteorological environment and the thermal environment showed a statistically significant significance, the difference between the measured items was not significant. The study found that the trees were generally pleasant to weather and thermal climate in the form of trees, and the differences were mostly documented.

• Proceedings of the Korean Institute of Landscape Architecture Conference
• /
• 2017.10a
• /
• pp.100-102
• /
• 2017

• Journal of the Korean Institute of Landscape Architecture
• /
• v.44 no.6
• /
• pp.84-97
• /
• 2016

This study was to investigate the user's thermal environments of the children's parks according to pavements and sunscreen types during periods of heat waves. The measurements were conducted at the sand pits, rubber chip pavement, shelters, and green shade ground of the two children's parks located in Jinju, Korea(Chilam: $N\;35^{\circ}11^{\prime}1.4{^{\prime}^{\prim}}$, $E\;128^{\circ}5^{\prime}31.7{^{\prime}^{\prime}}$, elevation 38m, Gaho: $N\;35^{\circ}09^{\prime}56.8{^{\prime}^{\prime}}$, $E\;128^{\circ}6^{\prime}41.1{^{\prime}^{\prime}}$, elevation 24m) over three days during 11-13, August, 2016. The highest ambient air temperatures at the Jinju Meteorological Office during the three measurement days were $35.9{\sim}36.8^{\circ}C$, which corresponded with the extremely hot weather. A series of experiments measured air temperature, relative humidity, wind velocity, black globe temperature, and long-wave and short-wave radiation of the six directions 0.6 m above ground level. The wet bulb globe temperature(WBGT) and the universal thermal climatic index(UTCI) were used to evaluate thermal stress. Surface temperature images of the play equipment were also taken using infrared thermography. Surface temperatures of the play equipment and grounds were used to evaluate burn risk through contact with playground materials. The results showed the following. The maximum air temperatures averaged over 1-hour period for three days were $36.6{\sim}39.4^{\circ}C$. The sun shades reduced those temperatures by up to $2.8^{\circ}C$(green shade) and $1.0^{\circ}C/2.3^{\circ}C$(shelters). The minimum relative humidity values averaged over 1-hour period for three days were 44~50%. The sun shades increased those humidity values by up to 6%(green shade) and 4%/6%(shelters). The risk of heat related illness at the measurement sites of the children's parks were extreme and high in the daytime hours. The maximum WBGT values averaged over a 30-minute period for three days were $31.2{\sim}33.6^{\circ}C$. The sun shades reduced those WBGT values by up to $2.4^{\circ}C$(green shade) and $0.5^{\circ}C/2.1^{\circ}C$(shelters) compared to sandpits, but would not block the risk of heat related illness in the daytime hours. The category of heat stress at the measurement sites of the children's parks were extreme and very strong in the daytime hours. The maximum UTCI values averaged over a 30-minute period for three days were $39.9{\sim}48.1^{\circ}C$. The sun shades reduced those UTCI values by up to $7.8^{\circ}C$(green shade) and $4.1^{\circ}C/8.2^{\circ}C$(shelters) compared to sandpits, but could not lower heat stress category from extreme and very strong to strong and moderate in the daytime hours. According to the burn threshold criteria when skin was in contact with playground materials, the maximum surface temperature of the stainless steels($70.8^{\circ}C$) surpassed three seconds $60^{\circ}C$ threshold for uncoated steel, that of the rubber chip($76.5^{\circ}C$) surpassed five seconds $74^{\circ}C$ threshold for the plastic, that of the plastic slide($68.5^{\circ}C$) and seats($71.0^{\circ}C$) surpassed the one min $60^{\circ}C$ threshold for plastic, respectively. The surface temperatures of shaded play equipment were lower approximately $20^{\circ}C$ than those of play equipment exposed to the sun. Therefore, sun shades can block the risk of burns in daytime hours. Because of the extreme and high risk of heat related illness and extreme and high heat stress at the children's parks during periods of heat waves, parents and administrators must protect children from the use of playgrounds. The risk of burn when contact with play equipments and grounds at the children's parks during periods of heat waves, was very high. The sun shades are essential to block the risk of burn from play equipments and grounds at the children's parks during heat waves.

• Journal of Environmental Science International
• /
• v.25 no.2
• /
• pp.311-322
• /
• 2016

This study reduced and built Street Canyons created by skyscrapers in order to verify effect of Street Canyons by green wall within the city centre and analysed influence factors on temperature reduction according to applicative types of green wall in the lab. Applicative types were divided into three types such as non- greening type(Case A), one-side greening type(Case B), both side greening type(Case C). The result of analysis of each types showed that average temperature of Case B and Case C is respectively $1.0^{\circ}C$ and $1.7^{\circ}C$ lower than Case A. The result of analysis of WBGT was that the highest temperature was given by Case A($40.2^{\circ}C$) and second one was from Case B($39.8^{\circ}C$) and third one was from ($39.1^{\circ}C$) and in UTCI Case A records the highest temperature of $34.7^{\circ}C$ and Case B provided the second highest temperature of $33.9^{\circ}C$ and Case B gave the lowest temperature of $32.7^{\circ}C$. In PMV the highest temperature of 2.65 was from Case B and second one of 2.61 was from Case A and third one of 2.54 was from Case C. Duncan analysis of each types based on solar radiation and thermal comfort generated that there was analytical significance between Case A and Case B and Case B in terms of each types of average temperature reduction. The significance of thermal comfort in WBGT, MRT, PMV showed non-significance but, In UTCI it was analysed that there was significance between Case C and Case A.

• Journal of Environmental Science International
• /
• v.25 no.9
• /
• pp.1269-1281
• /
• 2016

This study evaporative cooling system a heat wave climate change and reduction of the inside and outside thermal environment change research. Measurement items included micro meteorological phenomena and measured comfort indices. A micro meteorograph of temperature, relative humidity, surface temperature, and the comfort indices of WBGT, UTCI, and PMV were measured. The difference in inside and outside temperatures were compared for different land types, with the largest difference found in Type A ($4.81^{\circ}C$), followed by Type B ($4.40^{\circ}C$) and Type C ($3.12^{\circ}C$). Relative humidity was about 10.43% higher inside due to water injection by the evaporative cooling system. Surface temperature was inside about $6.60^{\circ}C$ higher than the outside all types. WBGT were Type A ($3.50^{\circ}C$) > Type B ($2.71^{\circ}C$) > Type C ($1.88^{\circ}C$). UTCI was low heat stress inside than outside all types. PMV was analysed Type C for inside predicted percentage of dissatisfied 75%, other types was percentage of dissatisfied 100% by inside and outside. Correlation analysis between land cover type and temperature, surface temperature, pmv, utci. T-test analysed inside and outside temperature difference was significant in all types of land.

• Fire Science and Engineering
• /
• v.32 no.4
• /
• pp.35-41
• /
• 2018

The purpose of study intends to investigate effects of repetitive work and workload for body while wearing firefighting protective clothing in hot conditions and to provide the basic data for the safety of firefighter. The experimental temperature is WBGT $30^{\circ}C$ and the work intensity is 3, 9 METs. The experiment is processed 15 minutes (Ex1), 15 minutes rest (Rest), 15 minutes (Ex2) in order of time. A comparative experiment was carried out for firefighting school students(9 persons; $24.3{\pm}0.71$ years old) wearing firefighting protective clothing. When workload is increased from 3 METs to 9 METs, mean skin temperature change (33.3%), tympanic temperature change (242.9%), heart rate (36.2%), respiration rate (53.9%), RPE (81.6%), thermal Sensation (20.8%), weight loss (60.0%), glucose (-4.4%), lactate (41.7%) are statistically significantly higher. As a result, it is considered that repetitive work and workload have a strong effect on the body when wearing firefighting protective clothing in hot conditions.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.26 no.11
• /
• pp.1672-1681
• /
• 2002

To evaluate the thermal environments and the workload of farmers in the rice field in summer, this study investigated rice farmers' physiological, psychological responses, work postures, work clothes, air temperature and air humidity during the spraying pesticide in the rice field. Five career farmers (3 males, 2 females) volunteered as the subjects. During the spraying pesticide in the rice field, physiological responses were monitored continuously. The results were as follows. l. Farmers wore only raincoats not pesticide-proof clothing. 2. The value of WBGT, rectal temperature($T_{re}$), mean skin temperature(${\={T}}_{sk}$) were $24.9∼28.9^{\circ}C,\;37.8({\pm}0.3)^{\circ}C\;and\;33.6({\pm}0.6)^{\circ}C$, respectively. Clothing microclimate temperature($T_{cl}$) on the chest and back were $32.5({\pm}2.6)^{\circ}C\;and\;33.6({\pm}2.6)^{\circ}C$, respectively(p<0.00l). Humidity inside of the clothing ($H_{cl}$) was over 80%RH and heart rate(HR) was 112(${\pm}27$)bpm. We evaluated that the spraying pesticide was 'heavy work' by the Tre and HR. To four subjective questionnaires, all farmers expressed 'hard, hot, humid and uncomfortable' without individual difference at the end of works. We suggested that 1) the spraying pesticide in the rice field was a heavy work, 2) because the workload of farmers in the raincoat/pesticide-proof clothing can't be evaluated by only WBGT, assessors should measure physiological, psychological responses as well as thermal environments, 3) to alleviate farmers' heat strain, clothing manufacturers must consider not only the improvement of textile materials and clothing weight but also the designing of personal cooling equipment.