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The Atomic Age

  1953 Speech | Film [circa early 1950s] | 1955 Stamp
  1957 Booklet | 1958-59 Seal

1957 Booklet: Atomic Tests in Nevada

Atomic Tests in Nevada Booklet. In 1957 Mike McCollough was in the eighth grade at Townsite Elementary School in Henderson, Nevada. As part of the Civil Defense effort that year, he and all of his classmates were given a green booklet titled "Atomic Tests in Nevada." The booklet describes the importance of the atomic tests at the Nevada Proving Grounds and emphasizes the safety precautions that were taken to protect those both on- and off-site.

Henderson, in the Las Vegas Valley, is now part of the greater Las Vegas metropolitan area. Townsite Elementary School once stood where the Henderson Convention Center is located. McCollough donated his copy of "Atomic Tests in Nevada" to the Atomic Testing Museum in Las Vegas.

The following is excerpted from the booklet with original illustrations.

The Nevada Test Site of U.S. Atomic Energy Commission is used periodically for experiments or tests involving nuclear detonations of relatively low yield (explosive energy).

Forty-five nuclear fission weapons, weapon prototypes, and experimental devices were fired at the Nevada Test Site from January 1951 to June 1955. They ranged in yield from less than 1 kiloton up to considerably less than 100 kilotons. (A kiloton is equivalent to 1,000 tons of TNT.)

Despite their relatively low yield, Nevada tests have clearly demonstrated their value to all national atomic weapons programs. They have made important contributions to the development of a whole family of weapons, including ones for defense against attack. Because of them our Armed Forces are stronger and our Civil Defense better prepared.

Each test fired in Nevada is justified, before it is scheduled, as to national need for the data sought. Each Nevada test has successfully added to scientific knowledge needed for development and use of atomic weapons, and needed to strengthen our defense against enemy weapons. Most tests have been used additionally for basic research, such as biological studies, which could be conducted only in the presence of a full scale nuclear detonation.

Conducting low-yield tests in Nevada, instead of in the distant Pacific, also has resulted in major savings in time, manpower, and money. The saving of time is particularly important because of its contribution to the Nation's defense capability.

Every Test is Evaluated. PROTECTION OF THE PUBLIC
You people who live near Nevada Test Site are in a very real sense active participants in the Nation's atomic test program. You have been close observers if tests which have contributed greatly to building the defenses of our country and of the free world. Nevada tests have helped us make great progress in a few years, and have been a vital factor in maintaining the peace of the world.

Some of you have been inconvenienced by our test operations. Nonetheless, you have accepted them without fuss and without alarm. Your cooperation has helped achieve an unusual record of safety.

To our knowledge no one outside the test site has been hurt in six years of testing. Only one person, a test participant, has been injured seriously as a result of the 45 detonations. His was an eye injury from the flash of light received at a point relatively near ground zero inside the test site. Experience has proved the adequacy of the safeguards which govern Nevada test operations.

Potential Exposure Is Low
Any atomic detonation, even though small enough to be fired in Nevada, involves powerful forces. The effects of a detonation include flash, blast, and radio-active fallout. Your potential exposure to these effects will be low, and it can be reduced still further by your continued cooperation.

The low level of public exposure has been made possible by very close attention to a variety of on-site and off-site procedures.

Public protection began with selection of the site. Nevada Test Site was selected only after extensive studies of other possible locations. The testing site covers an area of more than 600 square miles, with an adjoining U.S. Air Force gunnery range of 4,000 square miles. The controlled areas are surrounded by wide expanses of sparsely populated land, providing optimum conditions for maintenance of safety.


A nuclear explosion releases tremendous energy, equivalent in a so-called "nominal" burst to about 20,000 tons of TNT. This energy is released as heat, light, blast, and nuclear radiation.

Nevada Test Site.

The heat energy, released instantaneously, produces very hot gases at a high pressure, and the outward movement of these gases creates a shock wave, which is capable of severe destructive effects in the immediate area.

The instantaneous release of light is so great that devices detonated in Nevada, when fired before dawn have produced a flash visible 400-600 miles away. At a distance of about 6 miles, the brilliant flash from a 20-kiloton burst -- used as an example throughout this section -- is 100 times brighter than the sun.

Nuclear radiation is released as particles and waves (similar to X-rays) of energy. A portion of the radiation is released instantaneously in the form of neutrons (particles) and gamma rays (or waves).

The remainder of the radiation is given off over a period of time by the "fission products" created during the nuclear detonation.

For each 20 KT of explosive energy, about two pounds of radioactive materials are produced. In these 2 pounds are a variety of different radioactive substances varying in half-life from a fraction of a second to many years.


We cannot see, feel, smell, taste, or hear nuclear radiation. Consequently it may seem to be more difficult to understand than are light and sound waves from Nevada tests.

In order to help you understand radioactive fallout, we have appended to this booklet a discussion of the units used in measuring radiation, natural radioactive background, and the effects of radiation on man, including possible effects on inheritance and life expectancy.

Please understand that in the following discussion of radioactive fallout, we are not talking about high-yield A-bombs or H-bombs tested elsewhere. We are not talking about radiation from enemy bombs designed to do the most damage possible. We are talking only about low yield tests, conducted under controlled conditions at Nevada Test Site.

The Atomic Cloud
As the fireball rises, the atomic cloud forms. If dirt and debris have been drawn up into it, they become coated with radioactive materials and immediately start falling to earth. As the cloud rises, it expands, begins losing its radioactivity by decay, and floats away.

The radioactive particles within the cloud are initially of a wide range of sizes. Extremely small particles are apt to be fission products; larger particles are more likely to consist of fission products condensed on dust and debris of the air or sucked up from the ground.


As the radioactive particles begin to descend to earth, they are carried transversely by the winds. The larger particles tend to settle first. Fallout -- the descent of the particles back to earth -- may occur in the immediate vicinity of the burst or thousands of miles away.


Fallout Can Be Inconvenient
Fallout of very minute intensity can interfere temporarily with some industrial and research enterprises not only near the test site but elsewhere in the United States.

Interference in normal operations may occur in the uranium prospecting and mining business, in industrial and commercial processes where there are radiation controls, in the photographic industry, in low-level radiation research, etc.

Similar interference is, of course, caused by any United States or foreign tests. To help avoid or reduce such interference, Nevada series and individual shots are publicly announced.


Road Closed.

Warnings and Procedures
As in past series, every effort will be made to warn people away from the test site and the bombing range.

Helicopter and light aircraft sweeps of close-in predicted fallout areas will be made before a shot and any persons found there will be warned to leave. Like sweeps will be made following a shot. Stockmen will be advised if there are indications their stock has been exposed.

An extensive radiation monitoring system will be in operation in the test site region.


The effects of the flash of light are essentially no different from those of sunlight. If you look directly into the sun (or at photographer's flash bulb), you get black spots in front of your eyes for a few seconds or a few minutes. If you were much closer to the sun or if you used binoculars, eye damage might result.

On-site the thermal (heat) waves can injure eye tissues and cause permanent eye damage if one looks directly at the fireball. This is also true in the air above the test site. At shot time all personnel on or above the test site wear extremely dark glasses or turn away; binoculars are prohibited; and road traffic may be halted.

Off-site the same precautions should be followed by anyone in line of sight with the expected burst. The flash can cause "black spots" so that momentarily you can't see, or the flash can startle you if it is unexpected. This effect can be experienced at night many miles away. The greatest caution needs to be used by drivers of vehicles or the pilots of aircraft who might have an accident if momentarily unable to see, or if startled.

Enjoy the View.

The brightness of the light striking your eyes depends of course on whether it is night or day (at night, more light enters the dilated pupils), whether there is direct line of sight of the fireball, on distance, on atmospheric conditions, and to some extent on the yield of the device.

A majority of Nevada shots must be in the predawn hours of darkness and will require precautions against flash.

Past Experience With Flash
There have been no known cases of serious eye damage from light effects to people off-site. Some observers on nearby mountains, who did not wear dark glasses nor turn away, have reported temporary blind spots.


Shock waves go out in all directions from the detonation. Some strike the earth and are dissipated. Some are reflected back to earth from various atmospheric layers. If they reach earth at an inhabited point they may be felt or heard.

Wave propagated through the troposphere (up to 6 miles high) cause sharp cracking and banging noises in the nearby site region. The strength of waves hitting in the nearby region depends on temperature and wind structure of the atmosphere, on altitude of the detonation , and on its yield. The point at which the wave will strike the earth is dictated by the altitude of the detonation and the meteorological structure of the atmosphere at that moment. Wind direction causes directional variation in blast. If the weather creates a lens effect in the atmosphere, blast intensity may be focused at a particular point and may be strong enough to break windows.


Past Experience With Blast
Light damage to structures and broken windows have resulted within 100 miles of the test site. Most of these were in the two 1951 series, on a line from the test site through Las Vegas and Henderson. Blast has been heard, but it is not known to have caused damage, at greater distances, including Los Angeles, Calif., and Albuquerque, N. Mex.

Off-Site Warnings and Procedures for Blast
The Nevada Test Organization has a blast prediction and blast recording unit and devotes considerable effort to forecasting where blast may strike. High explosive shots are fired shortly before the nuclear test so the resulting blast can be recorded on sensitive instruments in communities around the test site. If the weather remains constant these provide a good indication of where the blast will strike, but if the atmosphere changes only slightly the point of impact may vary by miles. If strong blast is indicated for any community, under apparently meteorological conditions, the shot may be postponed.

When a possibility of slight damage to any community is indicated, the community is warned to open windows and doors to equalize pressure.


Since the first Nevada test series, the AEC has contracted with the General Adjustment Bureau to receive and to investigate claims for damages arising from test operations. An office is maintained in Las Vegas, Nev.

Blast Claims.

The Bureau's investigative teams are supplemented by engineers, architects, veterinarians, or other experts from the area where the asserted damaged occurred. The investigation is thorough, in order to determine whether or not the claimed loss actually resulted from a test detonation. If found to be justified , settlement is relatively prompt.

If a claim is refused, or if it exceeds $5,000 you may still sue in Federal Court.

Almost all of the claims made as a result of tests have been for asserted damage made as a result of tests and a large majority of these were from the Las Vegas area as a result of the first two test series.


Quite by chance, some unusual weather accompanied Nevada tests during the spring of 1952 and 1953 (this was not the case in 1955). Lacking anything else to blame, some people thought the tests caused the bad weather.

You have lived next door to the test site long enough to know that weather is very important to us. We sometimes wait for days and days until the right period of strong winds. In such a case, strong winds will of course follow a shot.

For example, people in Las Vegas have noted during the day of an early morning test that a wind storm moved in from the northwest, seemingly from the test site. They haven't always realized that the same storm was moving toward them across California at shot time, and the Test Organization was taking advantage of the calmer period before the storm in order to control test effects. To a Tonopah resident, the sequence would have been different as he could have seen the early morning flash in the southeast, then watched the clouds move in from the northwest.

The U.S. Weather Bureau experts, and those in our Armed Forces, have reviewed all of the facts. They have found no indication at all that Nevada tests change the weather anywhere in any respect.

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