CT, or computed tomography, does not emit much radiation indoors. Computed tomography indoor examination will only have radiation, because there are patients when the examination, the machine will release rays, but at this time the doors and windows of the examination room are tightly closed, and indoor walls, doors, etc. are specially treated, there is anti-radiation effect, there is no radiation outdoors, the doctor will not generally have an impact. For the patients, first of all, the computed tomography examination time is short, a single examination, the amount of radiation suffered by the patient is within the safe range, will not cause serious adverse reactions to the patient. The second is that before the examination, the doctor will do a good job of protection for the patient, such as the use of lead aprons, clothing, etc. to cover the parts that do not need to be scanned, which can reduce the rays received by the body. When the examination is ready, the patient is the only one in the examination room, and the accompanying persons, etc., are in the outer room and will not receive the rays of the scan, and other people will not be affected. Although the radiation in the computed tomography scanning room is not large, it is necessary to arrange for the examination of computed tomography under the guidance of a doctor according to the needs of the condition, and not to abuse the examination at will.