Superficial injuries to the skin caused by external abrasion of the skin on the surface of the body, visible to the naked eye with bleeding or oozing blood and tissue fluid exudation. Lighter trauma, small area of abrasions, by saline and other rinses coated with 20% red mercury or 1% gentian violet (gentian violet should not be applied to the face to avoid pigmentation), or 2% tincture of iodine, the latter disinfection is reliable, but there is significant pain after coating (trauma in more than 0.5 square centimeters is not applicable). If the area of abrasion is large or embedded in more mud, sand and other foreign bodies, it should be cleaned thoroughly, which is not only necessary to disinfect the wound to avoid infection, but also to avoid leaving foreign bodies causing scars and pigmentation. Therefore, it is important to be patient and carefully pick out the foreign bodies. If saline is not available on site, cold boiled water or even tap water can be used to wash the wound, and then the wound can be coated with medicine, including Yunnan Baiyao powder and antibiotic powder.