Fallout in the context of "Plutonium"

Nuclear weapons tests are experiments carried out to determine the performance of nuclear weapons and the effects of their explosion. Over 2,000 nuclear weapons tests have been carried out since 1945. Nuclear testing is a sensitive political issue. Governments have often performed tests to signal strength. Because of their destruction and fallout, testing has seen opposition by civilians as well as governments, with international bans having been agreed on. Thousands of tests have been performed, with most in the second half of the 20th century.

The first nuclear device was detonated as a test by the United States at the Trinity site in New Mexico on July 16, 1945, with a yield approximately equivalent to 20 kilotons of TNT. The first thermonuclear weapon technology test of an engineered device, codenamed Ivy Mike, was tested at the Enewetak Atoll in the Marshall Islands on November 1, 1952 (local date), also by the United States. The largest nuclear weapon ever tested was the Tsar Bomba of the Soviet Union at Novaya Zemlya on October 30, 1961, with the largest yield ever seen, an estimated 50–58 megatons.

Radiological warfare is any form of warfare involving deliberate radiation poisoning or contamination of an area with radioisotopes, but without the use of nuclear weapons. While radiological weapons were researched and in some cases tested during the Cold War, there is no evidence any military has ever deployed operational radiological weapons, although they have been used for assassination.

Nuclear warfare, both via fission and fusion weapons, creates radioisotopes in the form of fission products and neutron-activated surface material. This fallout is incorporated into military planning. Neutron bombs are designed to maximize the lethal radiation area and minimize the blast. These uses are generally not considered direct radiological warfare, but salted bombs, which maximize radioisotope production in a nuclear blast, are.

A dirty bomb or radiological dispersal device is a radiological weapon that combines radioactive material with conventional explosives. The purpose of the weapon is to contaminate the area around the dispersal agent/conventional explosion with radioactive material, serving primarily as an area denial device against civilians. It is not to be confused with a nuclear explosion, such as a fission bomb, which produces blast effects far in excess of what is achievable by the use of conventional explosives. Unlike the rain of radioactive material from a typical fission bomb, a dirty bomb's radiation can be dispersed only within a few hundred meters or a few miles of the explosion.

Dirty bombs have never been used, only tested. They are designed to disperse radioactive material over a certain area. They act through the effects of radioactive contamination on the environment and related health effects of radiation poisoning in the affected populations. The containment and decontamination of victims, as well as decontamination of the affected area require considerable time and expenses, rendering areas partly unusable and causing economic damage. Dirty bombs might be used to create mass panic as a weapon of terror.