In 1950, the U.S. government published a pamphlet with the hopeful title of Survival Under Atomic Attack. The publication came five years after the United States dropped atomic bombs on Japan and one year after the Soviet Union developed its own atomic device. Both nations would develop more powerful thermonuclear weapons—hydrogen bombs—in the early years of the decade.

The booklet begins with an assessment of survival:

What are your chances? If a modern A-bomb exploded without warning in the air over your home town tonight, your calculated chances of living through the raid would run something like this:

Should you happen to be one of the unlucky people right under the bomb, there is practically no hope of living through it. In fact, anywhere within one-half mile of the center of explosion, your chances of escaping are about 1 out of 10.

On the other hand, and this is the important point, from one-half to 1 mile away, you have a 50-50 chance.

Under that hopeful assumption, the booklet goes on to explain flash burns and radiation before listing six survival tips for atomic attacks:

1. Try to get shielded
2. Drop flat on ground or floor
3. Bury your face in your arms
4. Don’t rush outside right after a bombing
5. Don’t take chances with food or water in open containers
6. Don’t start rumors

Easier said than done. In the Cold War novel Distant Early Warning, the residents of Pennsboro have a mixed reaction to that advice. Patriotic to the core, the Gouchers build a fallout shelter in their backyard. The rest of the neighbors are on their own. At work, Marshall Andersen hears the sirens blare and wonders if he can get home in time. His wife Georgia unplugs the iron and draws the curtains against a possible blast. Their son, Wil, ducks and covers in the hallway at school, frozen by the sound of impending doom.

The pamphlet offers a more hopeful appraisal.

“To sum up, If you follow the pointers in this little booklet, you stand far better than an even chance of surviving the bomb’s blast, heat, and radioactivity.”

That’s a big if, even for the 1950s.

Jeff Widmer’s latest book is Distant Early Warning, a novel of the Cold War.