Currently there are no less than thousands of chemical substances that can cause chemical burns. Chemical burns are characterized by the fact that certain chemicals, in addition to immediate damage after contact with the body, can continue to invade or be absorbed, resulting in progressive local damage or systemic poisoning. The degree of damage depends on the dose, concentration and duration of exposure, in addition to the nature of the chemical substance. The nature of the damaged substance should be understood when dealing with it, so that corresponding measures can be taken. 1.General treatment principle Immediately remove the clothes impregnated by chemical substances and rinse with a large amount of water continuously for a long time. Special attention should be paid to the rinsing of the eyes and the five senses, because the injury can lead to blindness or other consequences. The use of neutralizing agents in first aid is not the best policy. In addition to delay, damage may be aggravated by improper selection in a hurry or by heat production in the neutralization reaction. Early infusion of fluids can be higher, with the addition of diuretics to expel toxic substances. Deep burns should be excised as early as possible with necrotic tissue and skin grafting. Has been clearly for chemical toxic injuries, should be selected with the appropriate antidote or antagonist. 2, acid burns longer seen acid burns for strong acids (sulfuric acid, hydrochloric acid, nitric acid). The common feature is to make the tissue protein coagulation and necrosis, can make the tissue dehydration; do not form blisters, leather-like scabs, generally not to the deep erosion, but the time delayed decab. First aid is to flush the injury with plenty of water, and then treat it as a general burn. In addition, some corrosive acid burns: such as carbolic acid, its dehydrating effect is not as strong as the above-mentioned strong acid, but can be absorbed into the blood circulation and damage the kidneys. Carbolic acid is not easily dissolved in water, and can be cleaned with 70% alcohol after rinsing with water. Another example is hydrofluoric acid, which is very penetrating and can dissolve lipids and continue to invade around and deeper, expanding and deepening the damage especially heavily. Immediate treatment is still a lot of water rinse, followed by 5% to 10% calcium gluconate (0.5ml/cm2) added to 1% procaine peri-infiltration injection, so that the residual hydrofluoric acid into calcium fluoride, can stop its continued diffusion and invasion. 3, alkali burns strong alkali such as sodium hydroxide, potassium hydroxide, etc. can also dehydrate the tissue; but combined with tissue proteins into a complex, can saponify adipose tissue, saponification can produce heat, continue to damage the tissue, alkali ions can penetrate to the depths. Pain is more intense, the wound can be expanded and deepened, and healing is slow. First aid should be a lot of water rinsing, rinsing time should be even longer. Deep alkali burns are suitable for early scab cutting and skin grafting. Burns of quicklime (calcium hydroxide) and calcium carbide (C2Ca) in alkali burns must be removed before rinsing with water to remove particles or powder from the wound to avoid heat production after adding water.