An area, accessible to personnel, in which radiation exists, originating in whole or in part within radioactive material, at such levels that a major portion of the body could receive a dose in excess of 5 millirems (5 ¥ 10-5 sievert) during any single hour or a dose in excess of 100 millirems (100 ¥ 10-5 sievert) during any five consecutive days.
