Optical Properties of the Human Epidermis

et al. 2019

ENG

In a summer outdoor space, the influence of shortwave length solar radiation on the human body is strongly apparent, heat is retained in the body, and the risk of heat disorders such as heat stroke increases. To avoid this, it is essential to seek shade to avoid the influence of shortwave length solar radiation. In addition, natural ground surfaces such as green spaces and water surfaces are useful in reducing the air temperature. It is indispensable to consider climate mitigation effect of outdoor space. The purpose of this study is to clarify the influence of the thermal environment of an outdoor space on the human body in rural and suburban regions where paddy fields remain. Subject experiments were conducted to examine the relationship between the thermal environment evaluation index enhanced conduction-corrected modified effective temperature (ETFe) in an outdoor space and the physiological and psychological responses of the human body. Experiment sites were selected with consideration for the natural ground surface such as bare ground where the surface is gravel or soil; paved ground such as concrete, asphalt or blocks; green areas covered in plants; and water surfaces, as well as the sky factor due to buildings or trees etc. and the proportion of the solid angle of components of greenery and water etc. comprising the solid angle of the total celestial sphere. A ground surface feature with a high heat capacity may promote sensation of hot and deteriorate the thermal sensation. A landscape of thick vegetation with a high green factor may have a strong feeling of confinement, which can make it somewhat hot and somewhat uncomfortable thermal environment due to the sense of stagnation.

Section: Resultsmentioning

confidence: 99%

Effects of Outdoor Thermal Environment upon the Human Responses

Kurazumi¹,

Kondo²,

et al. 2019

ENG

“…The value of Hendler et al [51], found from the reflectance by the skin of electromagnetic waves with wavelengths of 3 μm or more, was used for the emissivity of the human body. The values of Hendler et al [51] and Elam et al [52], found from the reflectance by skin of electromagnetic waves with wavelengths of 3 μm or less, were used for the solar radiation absorption coefficient of the human body. The short-wave solar radiation heat gain of the human body is affected by the shortwave solar radiation absorption.…”

Section: Relationship Between Air Temperature and Mean Skin Temperaturementioning

confidence: 99%

Seasonal Differences of Psychological and Physiological Responses in Tropical Urban Climate

Kurazumi¹,

Ishii²,

et al. 2017

Health

This research aims to use the outdoor thermal environment evaluation index ETFe to quantify effects on the thermal sense of the human body of a tropical region climate with small annual temperature differences, and to examine seasonal differences in the thermal sense. Given that the average temperature of the earth is forecasted to rise, studying the effects on the human body from outdoor thermal environments in tropical regions is important for considering how to spend time outdoors in the future. This study clarifies seasonal differences in effects on the human body by comparing the effects on the thermal sensations of the human body from outdoor thermal environments in the winter and the dry season of Bangkok, Thailand in the tropics. The mobile measurements were carried out on the campus of Chulalongkorn University, Bangkok, Thailand. The subjects reported the thermal sensation and the thermal comfort that they experienced while exposed at the observation point. Air temperature, humidity, air velocity, short-wave solar radiation, long-wave thermal radiation, ground surface temperature, sky factor and the ratio of green and water surface solid angles were measured. We found no large seasonal difference between the winter and the dry season in skin temperature due to body temperature regulation. It is clear that in the winter season, people prefer a lower temperature than in the dry season, and in the dry season they tolerate higher temperatures than in winter. The effect of the seasonal difference appears in the amount of change to thermal sensation. We found that it is difficult for seasonal differences to greatly affect the amount of change to thermal comfort. We found that the effect of seasonal difference is that people show stronger responses to thermal comfort for thermal sensation 897in winter than in the dry season.

“…The value of Hendler et al [44] found from the reflectance by the skin of electromagnetic waves with wavelengths of 3 μm or more was used for the emissivity of the human body. The value of Hendler et al [44] and Elam et al [45] found from the reflectance by skin of electromagnetic waves with wavelengths of 3 μm or less was used for the solar radiation absorption coefficient of the human body. The short-wave solar radiation heat gain of human body is affected to the shortwave solar radiation absorption.…”

Section: Measured Parametersmentioning

confidence: 99%

Ethnic Differences in Thermal Responses between Thai and Japanese Females in Tropical Urban Climate

Kurazumi¹,

Ishii²,

et al. 2016

AJCC

The outdoor thermal environment might become worse than at present. It causes health injuries through the deterioration of the outdoor thermal condition. It is necessary to study how humans stay outdoors and adjust to thermal conditions. The purpose of this study was to clarify the influence of the outdoor tropical urban thermal environment on a subject who has been acclimatized to the environment studied using the outdoor thermal environment evaluation index ETFe. In addition, the tendency of human impacts was clarified through comparison to subjects from a temperate thermal environment region. As a result, it was found that an ETFe of up to 35˚C could be recognized as a temperate thermal environment. However, when the ETFe was greater than 40˚C, the subject could not tolerate the environment. There was not a significant difference of psychological reaction between Thai people, who were acclimatized to the tropical climate, and Japanese people, who were acclimatized to the temperate climate.