What is X-ray, she is a kind of invisible light, with penetrating, photosensitive, fluorescent, ionizing and biological effects. Human beings use these characteristics of X-rays, widely used in medical treatment. Gao Xuguang, Department of Pediatrics, The First Affiliated Hospital of Henan University of Traditional Chinese Medicine X-rays are absorbed through the human body, but also produce ionization, and cause a series of biochemical effects in body fluids and cells, so that the function of the tissue cells of the shape of the different degrees of influence on the normal human body has a certain potential harm. Therefore, the state has strict regulations on X-ray examination. And every year the health supervision department has to test the operation of X-ray machines and protective measures to ensure the safety of the examinee, the public and the operator. Medical X-ray examination radiation is extremely small, so the damage to the body is also extremely small, but after all, harmful, X-ray examination will not be included in the children and infants and physical examination program, except when you are sick and need X-ray examination. X-ray examination precautions: clothing, jewelry will cause artifacts, X-ray photography should be taken off; children moving will make the image blurred, affecting the diagnosis; examination is completed in time to leave the room. X-ray examination is harmful! When a child is sick, use X-ray examination based on the principle of “justification and quantitative optimization” to win the child’s health.