Impact of community shielding on radiological risk following a hypothetical nuclear explosion

The impact of a nuclear explosion is uncertain due to various factors such as the size of the explosion, the altitude at which it occurs, the weather conditions, and the surrounding terrain. Fission products released can have short-term or long-term effects, potentially leading to mortality. This study examined the effects of hypothetical nuclear detonations of 15 kT and 21 kT in a community using the HotSpot code. The main variables considered were shielding, wind speed, explosion power, time spent in the explosion zone, protection factors, and structure thickness. Existing structures significantly reduce external dose, prompt gamma, prompt neutron, and fallout. While a 21 kT explosion is more lethal than 15 kT, shielding is effective in attenuating radiation for both explosions. Proximity and duration of exposure to the explosion zone increase radiation effects. At higher velocities (4.5 m/s), the plume spreads more. High shielding effectiveness corresponds to low external dose levels. Concrete shielding is particularly more effective in attenuating and scattering radiation. Our study provides valuable guidance for decision-makers and the public on mitigation measures and sheltering prioritization in the event of a nuclear explosion.