Nuclear warfare is the most devastating of the weapons of mass destruction. Biological and chemical weapons kill and injure people but usually leave the infrastructure of civilization intact. Survivors are able to carry on.
Nuclear warfare not only kills and maims large numbers of people, it destroys or contaminates infrastructure, making areas uninhabitable for years. It destroys cities, farmland, and forests. Individuals surviving the initial blast may develop ARS (Acute Radiation Syndrome), and there is long-term risk of developing cancer due to excessive exposure to radiation. From the limited dirty bomb, an explosive device laced with radioactive material, to a massive hydrogen bomb, residual radioactive material deposited from an explosion can render an area uninhabitable for years. Apart from suitcase atomic bombs, dirty bombs are weapons most likely to be used by terrorists. Larger bombs are more sophisticated and are more likely to be used in wars between nations.
On August 6, 1945, the Enola Gay dropped the first atomic bomb on Hiroshima. A small bomb by current standards, it destroyed the city and initially killed 100,000 residents; another 40,000 died of burn complications, radiation sickness, and other related causes by the end of the year. The blast completely leveled 48,000 buildings, and only 6,000 of the original 76,000 buildings were left intact.
If you are near an explosion involving nuclear material and survive the initial blast, radiation exposure will be your main concern. You must limit your radiation exposure as best you can. The three factors you can use to protect yourself are shielding, distance, and time. Shielding between you and the source of the radiation will limit your exposure because the lead or other shield material will absorb part of the radiation. Distance is an important factor because your exposure is lessened considerably the farther you are from the source (the radiation dose is inversely related to the square of the distance from the source). It is also important to limit the time of exposure. The quicker you can evacuate the area, the better.
