What is a Dirty Bomb?

A dirty bomb, or radiological dispersion bomb, is a simple explosive device coupled with any radioactive material. It's cruder, cheaper, and much easier to assemble than a nuclear bomb. It does not produce a thermonuclear blast.

It combines the effect of conventional explosives, such as TNT, with radioactive material ("fallout") which contaminates the immediate blast area and area downwind from the blast.

High explosives inflict damage with rapidly expanding, very hot gas. The operating principle of the dirty bomb is the use of the gas expansion to propel radioactive material over a wide area, in addition to the destructive force of the blast itself.

When the explosive goes off, the radioactive material creates a wind-borne dust cloud that affects an area greater than the blast field of the original explosion.

The long-term destructive force of a dirty bomb comes from the ionizing radiation of the radioactive material. High-energy ionizing radiation, which includes alpha particles, beta particles, gamma rays and X-rays, are found in radioactive waste materials, which are much easier to obtain than weapons-grade plutonium.

Ionizing radiation can cause chemical reactions inside cells and damage DNA. A cell with a broken strand of DNA will either die, or the DNA may mutate. Ionizing radiation may also cause cells to malfunction, resulting in a wide variety of symptoms collectively referred to as radiation sickness.

Untreated, radiation sickness can be fatal, or mutate into various forms of cancer. A dirty bomb increases the radiation level above safe levels, and depending on the severity of the exposure, increases the risk of cancer and radiation sickness. The effect of radiation danger depends on the type and amount of radioactive material used in the bomb.