For patients who are about to undergo surgery, the sterilization of the surgical area is done according to the part of the body that needs to be operated on, and the extent of sterilization varies from one surgical site to another. For example, if a patient is going to undergo an abdominal surgery, the patient’s abdomen will be divided into the upper abdomen and the lower abdomen, and the scope of sterilization for the surgery will be different. If it is an upper abdominal surgery, the doctor takes the scope of sterilization, up to the nipple down to the pubic bone on both sides to the armpit area; lower abdominal surgery, the scope of the general is up to the raphe down to the upper third of the thighs, on both sides to the mid-axillary line as the dividing line. The scope of surgical sterilization will be controlled by the surgeon around 20cm around the wound or incision, and if the patient’s surgery has defective skin, the scope of sterilization should be expanded appropriately.