ple who were _outside_ the fringe area would not be affected by the
blast, heat or fire. Department of Defense studies show that in any
nuclear attack an enemy might launch against us, tens of millions of
Americans would be outside the fringe areas. To them--and to people in
the fringe areas who survived the blast, heat and fire--radioactive
fallout would be the main danger. Protective measures against this
danger can be taken.

WHAT IS FALLOUT?

When a nuclear weapon explodes near the ground, great quantities of
pulverized earth and other debris are sucked up into the nuclear cloud.
There the radioactive gases produced by the explosion condense on and
into this debris, producing radioactive fallout particles. Within a
short time, these particles fall back to earth--the larger ones first,
the smaller ones later. On the way down, and after they reach the
ground, the radioactive particles give off invisible gamma rays--like
X-rays--too much of which can kill or injure people. These particles
give off most of their radiation quickly; therefore the first few hours
or days after an attack would be the most dangerous period.

In dangerously affected areas the particles themselves would look like
grains of salt or sand; but the _rays_ they would give off could not be
seen, tasted, smelled or felt. Special instruments would be required to
detect the rays and measure their intensity.

FALLOUT WOULD BE WIDESPREAD

The distribution of fallout particles after a nuclear attack would
depend on wind currents, 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