Firefighting is an intense activity requiring heavy equipment, and many casualties among firefighter are caused by overexertion strain. This study investigated the actual workload of firefighting activity in a cold environment, and examining the necessity for breaks. Heart rate was measured for 24 hours with a Halter electrocardiograph during restricted service in 71 firefighters of city S in Hokkaido. The Cardiac-beats change during fire-fighting activity was measured, and maximum acceptable work duration (MAWD) as defined by Wu et al. (2001) was estimated as the workload. The average highest heart rate on the way to an alarm was 145.5 beat/min, and the heart rate was rising rapidly. The maximal heart rate during firefighting activity was statistically significant (P<0.01) with respect to activity duration. MAWD was greatly exceeded while fighting two small-scale fires, and the workload 5 minutes after the start reached 92.6 and 93.6% heart rate reserve (HRR), also 72.3 and 70.2%HRR for the whole activity on average. When fighting small-scale fire in a cold environment, firefighter need to be given a break and a shift after gaining control of the fire in order to prevent injuries and accident at deaths among firefighters at a disaster site and to reduce overexertion strain.

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Absorptance of clothing for short-wave radiation is an important factor in thermal comfort assessment based on the human body heat budget outdoor. Many researchers have adopted value of 0.7 prescribed in VDI 3787 as the solar absorptance of human body. However, the solar absorptance of human body should depend on material and color of clothing fabric substantially. The objective of this research is to identify solar absorptances of ten different clothing fabrics combining of two materials (100% cotton, 65% polyester/35% cotton) and five colors (black, white, gray, red and blue). The measurement was carried out in October and November, 2007. By using the pyranometers, total solar radiation, reflected solar radiation by the target fabric and surrounding ground surface, and transmitted solar radiation through the target fabric were measured. In a calculation of the solar absorptance, the reflected component from outside of the target fabric was separated from the measured reflected radiation by taking into consideration a configuration factor between the measuring sensor and the fabric. The following findings were obtained through the experiment. The identified solar absorptances of 100% cotton fabric were 0.61 for black, 0.17 for white, 0.36 for gray, 0.47 for red and 0.57 for blue. The identified solar absorptances of 65% polyester/35% cotton fabric were 0.61 for black, 0.17 for white, 0.35 for gray, 0.44 for red and 0.49 for blue. The solar absorptance of clothing fabric does not depend on direct and diffuse solar radiations. The solar absorptance of clothing fabric depends on material and color of fabrics.

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To investigate methods of preventing heat disorders among firefighters, experiments that simulated firefighting activity were performed under normal ambient conditions in summer (35°C, 30°C, 25°C; 70% relative humidity, respectively). In these experiments, 16 male firefighters pedaled a bicycle ergometer wearing firefighting equipment, and the physiological responses and subjective sensations were measured. At 35°C, the interval until the inner ear temperature elevated to 39°C was 20.0 minutes and the sweat production rate was 2.5 kg/h. At 30°C, these values were 26.6 minutes and 2.0 kg/h, respectively. However, at 25°C, the inner ear temperature had elevated to only 38.5°C after 40 minutes (the end point of the experiment) and the sweat production rate was 1.7 kg/h. RPE of the Borg scale and thermal sensation points differed significantly (p<0.05) among the three environmental conditions. Both values correlated with inner ear temperatures (p<0.001, respectively). When firefighting activities are performed in an environment over 30°C, reexamination of clothes, measures such as body cooling, fluid intake, or activity breaks should be considered.

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The purpose of this research is to verify techniques of adaptation to the local climate in traditional homes themselves, or in the lifestyle, in two villages in Yoshida-cho, Shimane Prefecture. This was done by measuring the outdoor and indoor climate, and conducting a questionnaire survey of residents regarding their lifestyle and actual living experience. The spatial distribution and variation over time in local climate were evaluated by using the ETV temperature index. This made it possible to capture the detailed effects of the amount of insolation and wind speed, which vary greatly due to the highly undulous mountain terrain, and the impact of long-wave radiation and clothing depending on the time and season. Although the thermal performance of buildings themselves eased slightly the effects of weather outside, the indoor temperature varied in response to the outdoor weather. The effect of solar radiation was particularly clear in the summer. The indoor climate was above the comfort zone in summer and below the comfort zone in winter. The results of questionnaire survey showed that, in summer, the lifestyle was adapted to the local climate, and residents frequently used techniques with lower energy consumption, such as refraining from using air-conditioners and making do with electric fans, regulating temperature with ventilation and clothing, and engaging in environment selection behavior. In winter, almost all households provided local heating with an electric or charcoal kotatsu. Open-type heaters were also used in many households, but the households who used them constantly tended to feel more dissatisfaction than those who used them intermittently or in an auxiliary fashion. Here too, creative techniques were used to avoid excessive energy consumption, such as wearing more clothing indoors.

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There are about 390 health resorts in Germany consisting of four types; balneotherapy, thalassotherapy, Kneipp therapy and climatotherapy health resorts. Forest walking in Germany, described as “terrain cure,” is carried out mainly in the climatotherapy health resorts located in forested areas. In the other health resorts, such as the Kneipp health ones, walking as exercise therapy does not place a specific value on the location; thus whether it was a forested area or not was not a concern. Although forest walking in German health resorts clearly is part of the medical regime, it is a minor therapy within the German medical system. This paper also noted that the concept of Shinrin-yoku (walking and/or staying in forest for health promotion) was not known in Germany. The concept of the relationship between forests and health, and the methods and purpose of forest walking was thought to be different between Germany and Japan. Shinrin-yoku in Japan is regarded as trees and/or forest directly influencing human health. Shinrin-yoku is concerning having a mainly psychological effect, such as mental stress reduction, while forest walking as a terrain cure in Germany is related mainly to being for the improvement of physical function; that is, by training in a characteristic physical forest environment (e.g. blocked off from the sunlight and on either the higher or lower slopes of a mountain).

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The effects of repeated foot bathing in carbon dioxide-rich water on humoral regulation of physiological functions were studied.
Subjects were five aged persons (4 females and 1 male, 87.4±5.9 years old), who were visiting a geriatric intermediate care facility. Each subject immersed their lower legs in artificially produced carbon dioxide-rich water (800–1000 ppm) at 40–41°C more than twice a week for three months. Hematological and blood biochemical parameters were measured before and 3 weeks and 3 months after the beginning of the repeated foot bathing. Mean corpuscular hemoglobin concentration increased significantly and mean corpuscular volume decreased significantly after 3 weeks and 3 months. In addition, red blood cell count and hemoglobin concentration increased significantly after 3 months. There are no significant changes in plasma levels of Fe, ferritin, and erythropoietin after 3 weeks and 3 months. Total protein concentration and albumin increased, and aldosterone and K⁺ increased significantly after 3 months.
These findings raise the possibility that the repeated carbon dioxide foot bathing affects various body functions not only regulated by autonomic nervous systems, but also regulated by humoral factors, such as hematopoietic functions, protein metabolism, and water-electrolyte metabolism.

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