whole-body irradiation, ionizing radiation exposure that affects the entire body. Short-term whole-body irradiation can cause injury or death in humans, mainly from damage to the GI tract and the bone marrow. However, such injury occurs only with doses far beyond the diagnostic range, such as with exposure to nuclear weapons. The absorbed dose equivalent limit for whole-body occupational exposure is 5 rem per year. The nonoccupational absorbed dose equivalent limit is 0.5 rem per year. Also called total body radiation.