Heat and humidity not only act on human physiology, but also reduce work productivity, condensing the world’s economic productivity and particularly affecting the developing countries in the tropical climate zone (18, 19). Excessive heat exposure is a health risk for all age groups (20). Kjellstrom et al. (9) described the physiological mechanisms behind health and productivity effects. A study shows that the largest proportion of heat effects is not reported cases of hyperthermia, but mainly increases in cardiovascular and respiratory hospitalizations and deaths (21). Beyond the acute heat stress, more chronic effects on the heart and kidneys may develop after repeated excessive body heating or dehydration (7).