Since the most hazardous fallout particles are the heaviest, they sink through the air and collect on streets and rooftops, making ideal shelters underground  or in the middle of high-rise buildings.
Sabendo que as partículas mais perniciosas são as mais pesadas, descem pelo ar e encobrem ruas e telhados, abrigos no subsolo ou no meio de prédios altos são os ideais.