News

Thermal stimulation and standard

Heat is the most common form of "energy" that cannot be destroyed but can only be transferred from one object to another. The heat exchange between the human body and its surroundings stimulates the subcutaneous thermoreceptor nerves, which produces the sensation of heat.

The human body produces heat all the time; the exact amount of heat depends on the individual's activity. The digestion of food, the production of water, gas and heat are all called metabolism. The human blood temperature must be maintained at around 37 to be comfortable and healthy. This temperature varies from person to person, but for anyone, a change in blood temperature of more than ±0.2℃ will be uncomfortable; more than ±2.5℃ may cause life-threatening or death. In order for the human body to maintain a constant internal temperature, the heat generated by metabolism must be removed in the same proportion as it is generated. Heat loss is mainly due to conduction, convection and evaporation. The skin on the outside of the human body or the lungs inside the body can dissipate heat. The efficiency of its heat dissipation depends on the local air conditions and the temperature of the environment.

The temperature of the human body surface is slightly lower than the blood temperature, but much higher than the surrounding air temperature. Therefore, heat must be dissipated from the skin to the surrounding air. This heat dissipation also depends on the temperature difference, the insulation of the clothes, and the speed of the air hitting the human body surface.