With the continuous popularization of safety knowledge, the number of large burns is now decreasing, and the number of hospitalized cases at the Hospital of An Hospital, for example, has decreased this year compared to previous years, while the number of emergency outpatient cases has increased, probably because of the increase in the number of small burns and the continuation of the three degrees of burn classification: Ⅰ degree burns: damage to the epidermal stratum corneum, hyaline layer, and granular layer. Local redness and swelling, so also known as erythematous burns. There is pain and burning sensation, slightly increased skin temperature, 3 to 5 days after the local from red to light brown epidermis wrinkled off and healed. There may be a short period of hyperpigmentation, without scarring. Shallow degree II burns: Injury to the superficial dermis, part of the hair growth layer is still alive. The area is red and swollen, with blisters of varying sizes, containing yellow or light red plasma-like fluid or protein-coagulated jelly. If there are no complications such as infection, the procedure will heal in about 2 weeks. Shortly after healing, there may be pigmentation, no scarring, and good skin function. Deep II degree burns: Injury below the papillary layer of the dermis, but some of the reticular layer still remains. Local swelling with occasional smaller blisters. Due to the residual hair follicles, sweat glands and other skin attachments in the dermis, epithelium can still be regenerated, and if there is no infection, it can usually heal on its own in 3-4 weeks. After healing, there may be scarring and local dysfunction caused by scar contraction. Third-degree burns: full-layer skin burns, which can reach deep into the muscle and even bone and internal organs. The skin is necrotic and dehydrated and then forms a scab, so it is also called a scab type burn. The trauma surface is waxy white or charred yellow, or even charred. It is dry, without exudate, cool, and painless to needling and hair-pulling. A coarse embolized dendritic vascular network (subdermal vascular plexus embolism) can be seen, which is more typical in the thin skin of the inner extremities. After healing, more scarring is formed, normal skin function is lost, and deformities are often caused. So how much heat exposure, and how long exposure will produce skin damage? Skin surface temperature of 44 ℃, the role of time not more than 6 hours, more than not cause local tissue damage; 44-51 ℃, each 1 ℃, the epidermal necrosis rate increased exponentially; 70 ℃ or more, causing epidermal necrosis contact time of no more than 1 second. After the burn, the early performance is mainly severe pain, it is recommended to use cold water to rinse, soak or cold compress on the trauma (the above method is called cold therapy) to reduce pain and stop the heat from continuing damage to reduce exudation and edema. Use 5-10 ℃ tap water or clean water can be used, do not use ice directly on the skin surface to avoid frostbite, cold therapy time to 2-3 hours is appropriate, or even longer. Do not use soy sauce or toothpaste to smear the burns, on the one hand, it is easy to cause infection in the burns, on the other hand, the coloring interferes with the physician’s judgment of the degree of burns. After the cold therapy, the patient’s pain is reduced, the trauma needs to be kept dry, if the doctor has been consulted, for the trunk and extremities trauma can be bandaged, change the medicine every other day, for shallow II degree trauma, about 2 weeks to heal; deep II degree trauma, it takes 3-4 weeks; III degree trauma, it is difficult to heal itself, if necessary, need to perform local anesthesia surgery. For head, face, neck, perineum, buttocks, etc., it is difficult to bandage, so it is possible to expose the scab treatment and apply burn cream for 2-3 days, and then follow up with the clinic to guide the follow-up treatment after the scab dries.