A major emergency affecting a large number of people may occur anytime and anywhere.It may be a peacetime disaster such as a flood, tornado, fire, hurricane, blizzard or earthquake. It could be an enemy nuclear attack on the United States.In any type of general disaster, lives can be saved if people are prepared for the emergency, and know what actions to take when it occurs.With the aid of Federal and State governments, cities and counties in all parts of the country are developing their local civil defense systems--the fallout shelters, supporting equipment and emergency plans needed to reduce the loss of life from an enemy attack.
nts, weather conditions and other factors. There is no way of predicting in advance what areas of the country would be affected by fallout, or how soon the particles would fall back to earth at a particular location.
Some communities might get a heavy accumulation of fallout, while others--even in the same general area--might get little or none. No area in the U.S. could be sure of not getting fallout, and it is probable that some fallout particles would be deposited on most of the country.
Areas close to a nuclear explosion might receive fallout within 15-30 minutes. It might take 5-10 hours or more for the particles to drift down on a community 100 or 200 miles away.
Generally, the first 24 hours after fallout began to settle would be the most dangerous period to a community's residents. The heavier particles falling during that time would still be highly radioactive and give off strong rays. The lighter particles falling later would have lost much of their radiation high in the atmosphere