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UNDERSTANDING THE HAZARDS OF NUCLEAR ATTACK
SUMMARY
1. The main hazards of a nuclear attack are blast, heat, fire, and fallout radiation.
2. You may be able to protect yourself against blast and heat by getting inside a shelter or taking cover, before the nuclear explosions occur. You may be able to avoid fire injuries by putting out small fires or escaping from large fires that might occur in your area.
3. You can protect yourself against fallout radiation by getting inside a fallout shelter-if possible, before fallout particles begin drifting down-and by staying there until you are told to come out by authorities who have the equipment to measure radiation levels.
4. After a nuclear attack, food and water would be available to most people, and it would be usable. If any fallout particles have collected, they could be removed before the food is eaten or the water is drunk. People suffering from extreme hunger or thirst should not be denied food or water, even if the available supplies are not known to be free of fallout particles or other radioactive substances.
5: Infants and small children should be fed canned or powdered milk (if available) for awhile after the attack, unless the regular milk supply is uncontaminated. They should not be given water that may contain radioactive substances, if other water known to be pure is available.
6. A person cannot "catch" radiation sickness from another person.
UNDERSTAND THE HAZARDS OF NUCLEAR ATTACK
When a nuclear bomb or missile explodes, the main effects produced are intense light (flash), heat, blast, and radiation. How strong these effects are depends on the size and type of the weapon; how far away the explosion is; the weather conditions (sunny or rainy, windy or still) ; the terrain (whether the ground is flat or hilly) ; and the height of the explosion (high in the air, or near the ground).
All nuclear explosions cause light, heat and blast, which occur immediately. In addition, explosions that are on or close to the ground would create large quantities of dangerous radioactive fallout particles, most of which would fall to earth during the first 24 hours. Explosions high in the air would create smaller radioactive particles, which would not have any real effect on humans until many months or years later, if at all. *
What Would Happen in an Enemy Attack
If the U.S. should be attacked, the people who happened to be close to a nuclear. explosion-in the area of heavy destruction-probably would be killed or seriously injured by the blast, or by the heat of the nuclear fireball.
People a few miles away - in the "fringe area" of the explosion would be endangered by the blast and heat, and by fires that the explosion might start. However, it is likely that most of the people in the fringe area would survive these hazards.
People 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 f
all 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 "'ould 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 ta,ke 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.
Fallout Causes Radiation Sickness
The invisible gamma rays given off by fallout particles can cause radiation sickness-that is, illness caused by physical and chemical changes in the cells of the body. If a person receives a large dose of radiation, he will die. But if he receives only a small or medium dose, his body will repair itself and he will get well. The same dose received over a short period of time is more damaging than if it is received over a longer period. Usually, the effects of a given dose 'Of radiation are more severe in very young and very old persons, and those not in good health.
No special clothing can protect people against gamma radiation, and no special drugs or chemicals can prevent large doses of radiation from causing damage to the cells of the body. However, antibiotics and other medicines are helpful in treating infections that sometimes follow excessive exposure to radiation (which weakens the body's ability to fight infections).
Almost all of the radiation that people would absorb from fallout particles would come from particles outside their own bodies. Only simple precautions would be necessary to avoid swallowing the particles, and because of their size (like grains of sand) it would be practically impossible to inhale them.
People exposed to fallout radiation do not become radioactive and thereby dangerous to other people. Radiation sickness is not contagious or infectious, and one person cannot "catch it" from another person.
Protection Is Possible
People can protect themselves against fallout radiation, and have a good chance of surviving it, by staying inside a fallout shelter. In most cases, the fallout radiation level outside the shelter would decrease rapidly enough to permit people to leave the shelter within a few days.
Even in communities that received heavy accumulations of fallout particles, people soon might be able to leave shelter for a few minutes or a few hours at a time in order to perform emergency tasks. In most places, it is unlikely that full-time shelter occupancy would be required for more than a week or two.
Many Kinds of Fallout Shelters
The farther away you are from the fallout particles outside, the less radiation you will receive. Also, the building materials (concrete, brick, lumber, etc.) that are between you and the fallout particles serve to absorb many of the gamma rays and keep them from reaching you.
A fallout shelter, therefore, does not need to be a special type of building or an underground bunker. It can be any space, provided the walls and roof are thick or heavy enough to absorb many of the rays given off by the fallout particles outside, and thus keep dangerous amounts of radiation from reaching the people inside the structure. A shelter can be the basement or inner corridor of any large building; the basement of a private home; a subway or tunnel; or even a backyard trench with some kind of shielding material (heavy lumber, earth, bricks, etc.) serving as a roof.
In addition to protecting people from fallout radiation, most fallout shelters also would provide some limited protection against the blast and heat effects of nuclear explosions that were not close by.
Chapter 4 (pages 23-32) discusses the various types of fallout shelters that people can use to protect themselves in case of nuclear attack.
Food and Water Would Be Available and Usable
From many studies, the Federal Government has determined that enough food and water would be available after an attack to sustain our surviving citizens. However, temporary food shortages might occur in some areas, until food was shipped there from other areas.
Most of the Nation's remammg food supplies would be usable after an attack. Since radiation passing through food does not contaminate it, the only danger would be the actual swallowing of fallout particles that happened to be on the food itself (or on the can or package containing the food), and these could be wiped or washed off. Reaping, threshing, canning and other processing would prevent any dangerous quantities of fallout particles from getting into processed foods. If necessary to further protect the population, special precautions would be taken by food processors.
Water systems might be affected somewhat by radioactive fallout, but the risk would be small, especially if a few simple precautions were taken. Water stored in covered containers and water in covered wells would not be contaminated after an attack, because the fallout particles could not get into the water. Even if the containers were not covered (such as buckets or bathtubs filled with emergency supplies of water) , as long as they were indoors it is highly unlikely that fallout particles would get into them.
Practically all of the particles that dropped into open reservoirs, lakes, and streams (or into open containers or wells) would settle to the bottom. Any that didn't would be removed when the water was filtered before being pumped to consumers. A small amount of radioactive material might dissolve in the water, but at most this would be of concern for only a few weeks.
Milk contamination from fallout is not expected to be a serious prob- lem after an attack. If cows graze on contaminated pasture and swallow fallout particles that contain some radioactive elements, their milk might be harmful to the thyroid glands of infants and small children. 'l'herefore, if possible, they should be given canned or powdered milk for a few weeks if authorities say the regular milk supply is contaminated by radioactive elements.
In summary, the danger of people receiving harmful doses of fallout radiation through food, water or milk is very small. People suffering from extreme hunger or thirst should not be denied these necessities after an attack, even if the only available supplies might contain fallout particles or other radioactive substances.
* These smaller particles would drift to earth more slowly, losing much of their radioactivity before they reached the ground, and would be spread by the upper winds over vast areas of the world.
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