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Lesson 11e - Understanding the Basics of Radiation |
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Man-made Radiation Sources The only difference between man-made sources of radiation and naturally occurring sources is the place from which the radiation originates. Consumer products, industrial products and treatments, and nuclear weapons testing are all sources of man-made radiation, but it might be surprising to know that radiation from medical sources constitutes the largest percentage of exposure for most people. Medical radiation sources |
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| X-rays
The type of rays emitted by X-rays are identical to gamma rays, except that an x-ray originates outside the nucleus of an atom, whereas gamma rays are generated from the inside of an atom. A typical radiation dose from a chest x-ray adds up to about 10 mrem. Including estimations from the contributions of other possible x-rays, such as those performed for dental procedures and emergency care, the total average annual dose to the general population from medical x-rays is 53 mrem. To find out about the history of x-rays, click on this link!!! |
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| Diagnosis and therapy
Presently, radioactive materials, far from causing cancers, are being used to treat and diagnose cancers, as well as other illnesses. These therapeutic and diagnostic radioactive sources add, approximately 14 mrem per year to the total average annual dose to the general population.
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Consumer products |
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| Common household appliances contribute about 10 mrem a year to the average person's yearly radiation dose. Televisions, older luminous dial watches, and many smoke detectors emit very small amounts of radiation into the average American home. |
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Industrial uses |
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| Many industries use radioactive materials or machinery for a wide variety of special testing or treatments. For example, tires are treated with radioactive materials to make them more durable; bottling plants use radioactive sensors to measure when bottles are full; quality control measures for hundreds of different industries include x- ray machines (radiography) that detect manufacturing faults in everything from pipe welds to engine blocks. The annual radiation exposure from these sources varies from region to region, depending on the different types of industry based in a given area. |
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Atmospheric testing of nuclear weapons |
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| The one man-made source of radiation which many people mistakenly believe offers the most radiation is actually an extremely small percentage of the annual exposure rate: residual fallout from atmospheric nuclear weapons testing conducted in the 1950's and early 1960's, nuclear power generation, and radiation from other activities, such as the tailings resulting from mining operations, are estimated to contribute less than 1 mrem a year to the 360 mrem total. As most nations have discontinued the practice of testing weapons in the atmosphere, the fallout, not the testing, is now considered the source of this radiation. |
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