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Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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General Kenneth Nichols and the Manhattan Project
Nichols
The Oak Ridger has published the latest in a series of articles about General Kenneth D. Nichols, the Manhattan Project, and the 1954 Atomic Energy Act. The series has been produced by Nichols’ grandniece Barbara Rogers Scollin and Oak Ridge (Tenn.) city historian David Ray Smith. Gen. Nichols (1907–2000) was the district engineer for the Manhattan Engineer District during the Manhattan Project.
As Smith and Scollin explain, Nichols “had supervision of the research and development connected with, and the design, construction, and operation of, all plants required to produce plutonium-239 and uranium-235, including the construction of the towns of Oak Ridge, Tennessee, and Richland, Washington. The responsibility of his position was massive as he oversaw a workforce of both military and civilian personnel of approximately 125,000; his Oak Ridge office became the center of the wartime atomic energy’s activities.”
We live in a radioactive world - humans always have. Radiation is part of our natural environment. We are exposed to radiation from materials in the earth itself, from naturally occurring radon in the air, from outer space, and from inside our own bodies (as a result of the food and water we consume). This radiation is measured in units called millirems (mrems).
The average dose per person from all sources is about 620 mrems per year. It is not uncommon, however, for any of us to receive less or more than that in a given year (largely due to medical procedures we may undergo). International Standards allow exposure to as much as 5,000 mrems a year for those who work with and around radioactive material.
The Interactive Dose Calculator appears below, but you can also download a printable version of radiation dose chart.
All figures for radiation exposure are average values.
Exposure depends on your elevation (how much air is above you to block radiation). Amounts listed are per year.
Elevations: Atlanta 1050; Chicago 595; Dallas 436; Denver 5280; Las Vegas 2000; Minneapolis 815; Pittsburg 1200; St. Louis 455; Salt Lake City 4400; Spokane 1890. USGS GNIS Search.
0 mrem
Terrestrial (from the ground)
House Construction
Power Plants
Internal Radiation *
Hours (0.5 mrem per hour in the air)
Medical Diagnostic Tests ‡
Number of millirems are per procedure and are average values. Actual numbers may vary.
Enter the number of procedures per year.
(10 mrem each)
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(1274 mrem each)
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Your Estimated Annual Radiation Dose:
* Average values.
** Some of the radiation sources listed in this chart result in an exposure to only one part of the body. For example, false teeth and crowns result in a radiation dose to the mouth. The annual dose numbers given here represent the "effective dose" to the whole body.
† The value is less than 1, but adding a value of 1 would be reasonable.
‡ Exposures for medical tests vary depending upon equipment and the patient. The doses listed are an average for an actual exposure.
How is radiation measured? The units used to measure radiation are the rem and the millirem (1/1,000th of a rem). The international unit for measuring radiation exposure is the sievert (Sv), and 1 Sv = 100 rems. Therefore, to convert from the mrem values above to mSv (millisievert), divide the value by 100.
Primary sources for this information are National Council on Radiation Protection and Measurements Reports: #92 Public Radiation Exposure from Nuclear Power Generation in the United States (1987); #93 Ionizing Radiation Exposure of the Population of the United States (1987); #94 Exposure of the Population in the United States and Canada from Natural Background Radiation (1987); #95 Radiation Exposure of the U.S. population from Consumer Products and Miscellaneous Sources, (1987); #100 Exposure of the U.S. Population from Diagnostic Medical Radiation (1989); and #160 Ionizing Radiation Exposure of the Population of the United States (2009).
