Duck and Cover

Duck and Cover is a suggested method of personal protection against the effects of a nuclear explosion, which the United States government taught to generations of United States school children from the early 1950s until the end of the Cold War in the late 1980s. It was intended to protect them in the event of both an unexpected nuclear attack, which, they were told, might come at any time without warning(although with the Ballistic Missile Early Warning System, and the Pinetree Line of the era, a surprise attack was unlikely) and in the event sufficient warning is given. Under the conditions of a surprise attack, immediately after they saw a flash they had to stop what they were doing and get on the ground under some cover—such as a table, or at least next to a wall—and assume a prone like position, lying face-down and covering their exposed skin and back of their heads with their clothes, or if no excess clothes such as a coat was available, to cover the back of their heads with their hands. Similar instructions were given in 1964 in the United Kingdom by Civil Defence Information Bulletin No. 5. and, in the 1980s, by the Protect and Survive series. Under the conditions where sufficient warning is given, they were told to find the nearest fallout shelter, or if one could not be found, any well built building to stay and shelter in.

Proponents argued that thousands could be saved through this precaution, without which people would instead run to windows to find the source of the big flash. During this time a shock wave would cause a glass implosion, shredding onlookers.

According to the 1946 book Hiroshima, in the days between the Hiroshima and Nagasaki atomic bombings in Japan, one Hiroshima policeman went to Nagasaki to teach police about ducking after the atomic flash. As a result of this timely warning, not a single Nagasaki policeman died in the initial blast. This allowed more surviving Nagasaki police to organize relief efforts than in Hiroshima. Unfortunately, the general population was not warned of the heat/blast danger following an atomic flash because of the bomb’s unknown nature. Many people in Hiroshima and Nagasaki died while searching the skies for the source of the brilliant flash.

Similarly, "Drop, Cover and Hold On" is taught in areas prone to earthquakes. Schools in some tornado-prone areas of the United States also practice tornado drills that involve children squatting and covering the backs of their heads.