CONELRAD recently posted a great piece that explores the origin of the famous fallout shelter sign that appeared across the country at the height of the Cold War. Worn and rusted, you can still see some of them today as lasting symbols of the atomic age.
The signs were the product of an almost palpable upswell of public survival-mania about whether or not family shelters were needed in American homes. Citizens and politicians were divided on the subject, fearful of neighbor turning against neighbor in the event of a Soviet nuclear attack. But soon, public shelters were to be designed for schools and buildings while existing ones from World War II had to be marked for reuse. Little thought was put into what signs these structures needed.