Duck and Cover was a suggested method of personal protection against the effects of a nuclear weapon which the United States government taught to generations of United States school children from the early 1950s into the 1980s. This was supposed to protect them in the event of an unexpected nuclear attack which, they were told, could come at any time without warning. 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 the fetal position, lying face-down and covering their heads with their hands.^[1] Similar instructions were given in 1964 in the United Kingdom by Civil Defence Information Bulletin No. 5.^[2] and, in the 1980s, by the Protect and Survive series.^[3]
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.^[4]
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.^[5][6]