Source: Armed Forces Radiobiology Research Institute's Medical Effects of Ionizing Radiation Course on CD-ROM (1999)
Delayed ionizing radiation dose (fallout)
Produced by fission products and neutron-induced radionuclides in the area around the explosion, especially downwind
Dispersed downwind with the fireball/debris cloud.
As the cloud travels downwind, the cooling and falling radioactive material settles on the ground creating a large swath of deposited material (fallout).
Fallout creates large areas of contamination and the ionizing radiation coming off the fallout which can damage tissues and penetrate through thin walls and glass.
Fallout can also contaminate the soil, food and water supply
Prohibitions against eating food and drinking water from affected areas will be issued