During the Cold War, children in schools were taught to “duck and cover” in the case of a nuclear event. This maneuver taught kids to run under their desks and maintain the fetal position. This was thought to be effective because the No. 1 concern from a nuclear blast was glass and other debris flying through the air, as well as heat. Of course, today we know about the far more dangerous effects of actual nuclear radiation, which covering your face with your hands will do little to protect against.