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Unprotected experiments in the U.S. in 1896 with an early X-ray tube (Crookes tube), when the dangers of radiation were largely unknown.[1]The history of radiation protection begins at the turn of the 19th and 20th centuries with the realization that ionizing radiation from natural and artificial sources can have harmful effects on living organisms.
Research in this area has focused on the three most common sources of radiation used for these applications, including gamma, electron beam, and x-ray radiation. [17] The mechanisms of radiation damage are different for polymers and metals, since dislocations and grain boundaries do not have real significance in a polymer.
Natural color X-ray photogram of a wine scene. Note the edges of hollow cylinders as compared to the solid candle. William Coolidge explains medical imaging and X-rays.. An X-ray (also known in many languages as Röntgen radiation) is a form of high-energy electromagnetic radiation with a wavelength shorter than those of ultraviolet rays and longer than those of gamma rays.
Monument to the X-ray and Radium Martyrs of All Nations erected 1936 at St. Georg hospital in Hamburg, commemorating 359 early radiology workers. The dangers of radioactivity and radiation were not immediately recognized. The discovery of x‑rays in 1895 led to widespread experimentation by scientists, physicians, and inventors.
2007 ISO radioactivity danger symbol intended for IAEA Category 1, 2, and 3 sources defined as dangerous sources capable of causing death or serious injury [1]. This article lists notable civilian accidents involving radioactive materials or involving ionizing radiation from artificial sources such as x-ray tubes and particle accelerators.
Alpha radiation is dangerous when alpha-emitting radioisotopes are inhaled or ingested (breathed or swallowed). This brings the radioisotope close enough to sensitive live tissue for the alpha radiation to damage cells. Per unit of energy, alpha particles are at least 20 times more effective at cell-damage than gamma rays and X-rays.
In 1999, Time placed Shoe-Store X Rays on a list of the 100 worst ideas of the 20th century. [29] [30] A shoe-fitting fluoroscope appeared on a 2011 episode of the History series American Restoration. [31] Its radionuclide source was found to be so dangerous that it was removed and replaced with a static X-ray. [32]
Extreme ultraviolet and higher frequencies, such as X-rays or gamma rays are ionizing, and these pose their own special hazards: see radiation poisoning. The field strength of electromagnetic radiation is measured in volts per meter (V/m). [2]