Thermal Radiation Calculator


Jean M. Bele

Physics Dept., Laboratory for Nuclear Science, MIT

Thermal radiation is electromagnetic radiation in the visible light spectrum that can be sensed as heat and light. Thermal radiation damage is a direct result of the fireball. The thermal radiation that the fireball creates strikes on exposed surfaces and is absorbed into the material. Thermal radiation can ignite wood frame buildings, vegetation, and other combustible materials at significant distances from the site of the nuclear explosion.


Notes: Calculation shows types of burns and approximate maximum distances for selected yields. It is based on scenarios in which the weather is clear, there are no obstacles to attenuate thermal radiation, and the weapon is detonated as a low-air burst to maximize the thermal effect.

Notes: The nuclear bomb dropped on Hiroshima during World War II yielded 15 kilotons and the one dropped on Nagasaki was almost 20 kilotons. Today most powerful nuclear weapon yields are over 1000 kilotons, almost 660 more powerful then the Hiroshima bomb.

For a specific effect, choose the energy yield of the nuclear weapon explosion (kilotons):