xxgeekpr0nxx: If you see a mushroom cloud from an atomic bomb, you’re supposed to stick your arm out
xxgeekpr0nxx: If you see a mushroom cloud from an atomic bomb, you’re supposed to stick your arm out and hold your thumb over the cloud. If the cloud is larger than your thumb, you’re in the radiation zone and should evacuate. This is what Vault Boy is doing in the Fallout series. -- source link