In recent years, the danger of peacetime nuclear accidents has become so prevalent that most medical centers are faced with the responsibility of providing for care of individuals exposed to such mishaps. Some major accidents in the United States, or within its testing program (1–4), as well as in foreign countries (5, 6), have already occurred. Radiologists are certain to be consulted on the subject of possible plans or means to care for the victim in such a situation. The National Naval Medical Center, Bethesda, Md., has been designated as the Radiation Exposure Evaluation Center for the U. S. Navy. In the preparation and planning required for such responsibility, the staffs of the Departments of Radiology and of Nuclear Medicine of that Command have devised a plan whereby, it is believed, persons involved in an ionizing radiation accident, or incident, would receive optimal medical care. The following discussion is a résumé of the present concept of an evaluation program for such cases. Some definition of terms seems in order. The word “accident” refers to a situation in which personnel are known to be exposed to excessive doses (exceeding the “maximum permissible doses” listed by the National Committee on Radiation Protection) of ionizing radiation which may result from: (a) damage to a nuclear reactor shield, or the reactor fuel container, or the escape of reactor coolant; (b) damage to a nuclear weapon, with resultant escape of nuclear fuel; (c) damage and resultant rupture of a container of a “sealed source” of a radioisotope, such as is used in medicine or industry; (d) a reactor excursion, or “run-away”; (e) accidental exposure to a “beam” of radiation or another source of radiation, be it from a nuclear reactor, a medical or industrial source of radioactivity, or a radiographic installation (x-ray unit); (f) any other possible excessive exposure. An “incident” is a situation whereby in any of the above situations, or perhaps in some not listed, personnel might have been exposed but no definite evidence of such exposure can be proved at the site. This latter situation may be very important from a medicolegal standpoint. Patient Evaluation at the Exposure Site The Navy has established two Radiation Disaster Teams, the East Coast unit being stationed at the Explosive Ordnance Disposal Center, Indian Head, Md. The medical element of this team, staffed by the National Naval Medical Center at Bethesda, primarily serves in an advisory capacity to the command of the military establishment nearest the accident or incident. In case of an actual accident, possible procedures for this team are as listed in the following table: Note: In this situation it will be difficult to evaluate the extent of exposure. If this is in doubt and the number of persons is small (20 or less), the safest procedure is to evacuate all.