30 to 60 minutes. Official website information of Xiankang electric heating belt shows that the temperature of the electric heating belt is high, and if it is used for too long, it will cause low-temperature burns to the skin, and the electric heating belt will cause the skin to be dry, resulting in discomfort symptoms such as dryness and itching. So the electric heating belt can be used for 30 to 60 minutes at a time.