document_title: X-ray

question_text: range of energy used in diagnostic x rays

question_tokens: range of energy used in diagnostic x rays

text: X-ray

text: History[edit]

text: Discovery[edit]

text: German physicist Wilhelm Röntgen is usually credited as the discoverer of X-rays in 1895, because he was the first to systematically study them, though he is not the first to have observed their effects. He is also the one who gave them the name "X-rays" (signifying an unknown quantity[4]) though many others referred to these as "Röntgen rays" (and the associated X-ray radiograms as, "Röntgenograms") for several decades after their discovery and even to this day in some languages, including Röntgen's native German.

text: X-rays were found emanating from Crookes tubes, experimental discharge tubes invented around 1875, by scientists investigating the cathode rays, that is energetic electron beams, that were first created in the tubes. Crookes tubes created free electrons by ionization of the residual air in the tube by a high DC voltage of anywhere between a few kilovolts and 100 kV. This voltage accelerated the electrons coming from the cathode to a high enough velocity that they created X-rays when they struck the anode or the glass wall of the tube. Many of the early Crookes tubes undoubtedly radiated X-rays, because early researchers noticed effects that were attributable to them, as detailed below. Wilhelm Röntgen was the first to systematically study them, in 1895.[7]

text: The discovery of X-rays stimulated a veritable sensation. Röntgen's biographer Otto Glasser estimated that, in 1896 alone, as many as 49 essays and 1044 articles about the new rays were published.[8] This was probably a conservative estimate, if one considers that nearly every paper around the world extensively reported about the new discovery, with a magazine such as Science dedicating as many as 23 articles to it in that year alone.[9] Sensationalist reactions to the new discovery included publications linking the new kind of rays to occult and paranormal theories, such as telepathy.[10][11]

text: Early research[edit]

text: The earliest experimenter thought to have (unknowingly) produced X-rays was actuary William Morgan. In 1785 he presented a paper to the Royal Society of London describing the effects of passing electrical currents through a partially evacuated glass tube, producing a glow created by X-rays.[12] This work was further explored by Humphry Davy and his assistant Michael Faraday.

text: In 1877 Ukrainian-born Ivan Pulyui, a lecturer in experimental physics at the University of Vienna, constructed various designs of vacuum discharge tube to investigate their properties.[13] He continued his investigations when appointed professor at the Prague Polytechnic and in 1886 he found that sealed photographic plates became dark when exposed to the emanations from the tubes. Early in 1896, just a few weeks after Röntgen published his first X-ray photograph, Pulyui published high-quality X-ray images in journals in Paris and London.[13] Although Pulyui had studied with Röntgen at the University of Strasbourg in the years 1873–75, his biographer Gaida (1997) asserts that his subsequent research was conducted independently.[13]

text: X-rays were generated and detected by Fernando Sanford (1854–1948), the foundation Professor of Physics at Stanford University, in 1891. From 1886 to 1888 he had studied in the Hermann Helmholtz laboratory in Berlin, where he became familiar with the cathode rays generated in vacuum tubes when a voltage was applied across separate electrodes, as previously studied by Heinrich Hertz and Philipp Lenard. His letter of January 6, 1893 (describing his discovery as "electric photography") to The Physical Review was duly published and an article entitled Without Lens or Light, Photographs Taken With Plate and Object in Darkness appeared in the San Francisco Examiner.[14]

text: Starting in 1888, Philipp Lenard, a student of Heinrich Hertz, conducted experiments to see whether cathode rays could pass out of the Crookes tube into the air. He built a Crookes tube (later called a "Lenard tube") with a "window" in the end made of thin aluminum, facing the cathode so the cathode rays would strike it. He found that something came through, that would expose photographic plates and cause fluorescence. He measured the penetrating power of these rays through various materials. It has been suggested that at least some of these "Lenard rays" were actually X-rays.[15]

text: Hermann von Helmholtz formulated mathematical equations for X-rays. He postulated a dispersion theory before Röntgen made his discovery and announcement. It was formed on the basis of the electromagnetic theory of light.[16] However, he did not work with actual X-rays.

text: In 1894 Nikola Tesla noticed damaged film in his lab that seemed to be associated with Crookes tube experiments and began investigating this radiant energy of "invisible" kinds.[17][18] After Röntgen identified the X-ray Tesla began making X-ray images of his own using high voltages and tubes of his own design,[19] as well as Crookes tubes.

text: In November 1896, the inventor Dr. Robert D'Unger proposed a X-Ray telephot, supposed able to make transmission of pictures by telegraph wire.[20]

text: Wilhelm Röntgen[edit]

text: On November 8, 1895, German physics professor Wilhelm Röntgen stumbled on X-rays while experimenting with Lenard and Crookes tubes and began studying them. He wrote an initial report "On a new kind of ray: A preliminary communication" and on December 28, 1895 submitted it to Würzburg's Physical-Medical Society journal.[21] This was the first paper written on X-rays. Röntgen referred to the radiation as "X", to indicate that it was an unknown type of radiation. The name stuck, although (over Röntgen's great objections) many of his colleagues suggested calling them Röntgen rays. They are still referred to as such in many languages, including German, Hungarian, Danish, Polish, Swedish, Finnish, Estonian, Russian, Japanese, Dutch,Georgian and Norwegian. Röntgen received the first Nobel Prize in Physics for his discovery.[22]

text: There are conflicting accounts of his discovery because Röntgen had his lab notes burned after his death, but this is a likely reconstruction by his biographers:[23][24] Röntgen was investigating cathode rays from a Crookes tube which he had wrapped in black cardboard so that the visible light from the tube would not interfere, using a fluorescent screen painted with barium platinocyanide. He noticed a faint green glow from the screen, about 1 meter away. Röntgen realized some invisible rays coming from the tube were passing through the cardboard to make the screen glow. He found they could also pass through books and papers on his desk. Röntgen threw himself into investigating these unknown rays systematically. Two months after his initial discovery, he published his paper.[citation needed]

text: Röntgen discovered their medical use when he made a picture of his wife's hand on a photographic plate formed due to X-rays. The photograph of his wife's hand was the first photograph of a human body part using X-rays. When she saw the picture, she said "I have seen my death."[25]

text: Advances in radiology[edit]

text: There was immediate interest from researchers for the X-ray. A.A.Campbell Swinton, Nikola Tesla were amongst the firsts to test the new discovery. In 1896, Thomas Edison investigated materials' ability to fluoresce when exposed to X-rays, and found that calcium tungstate was the most effective substance. Around March 1896, the fluoroscope he developed became the standard for medical X-ray examinations. Nevertheless, Edison dropped X-ray research around 1903, even before the death of Clarence Madison Dally, one of his glassblowers. Dally had a habit of testing X-ray tubes on his hands, and acquired a cancer in them so tenacious that both arms were amputated in a futile attempt to save his life.

text: The first use of X-rays under clinical conditions was by John Hall-Edwards in Birmingham, England on 11 January 1896, when he radiographed a needle stuck in the hand of an associate.[26] On February 14, 1896 Hall-Edwards was also the first to use X-rays in a surgical operation.[27] In early 1896, several weeks after Röntgen's discovery, Ivan Romanovich Tarkhanov irradiated frogs and insects with X-rays, concluding that the rays "not only photograph, but also affect the living function".[28]

text: The first medical X-ray made in the United States was obtained using a discharge tube of Pulyui's design. In January 1896, on reading of Röntgen's discovery, Frank Austin of Dartmouth College tested all of the discharge tubes in the physics laboratory and found that only the Pulyui tube produced X-rays. This was a result of Pulyui's inclusion of an oblique "target" of mica, used for holding samples of fluorescent material, within the tube. On 3 February 1896 Gilman Frost, professor of medicine at the college, and his brother Edwin Frost, professor of physics, exposed the wrist of Eddie McCarthy, whom Gilman had treated some weeks earlier for a fracture, to the X-rays and collected the resulting image of the broken bone on gelatin photographic plates obtained from Howard Langill, a local photographer also interested in Röntgen's work.[29]

text: In 1901, U.S. President William McKinley was shot twice in an assassination attempt. While one bullet only grazed his sternum, another had lodged somewhere deep inside his abdomen and could not be found. A worried McKinley aide sent word to inventor Thomas Edison to rush an X-ray machine to Buffalo to find the stray bullet. It arrived but wasn't used. While the shooting itself had not been lethal, gangrene had developed along the path of the bullet, and McKinley died of septic shock due to bacterial infection six days later.[30]

text: Hazards discovered[edit]

text: With the widespread experimentation with x‑rays after their discovery in 1895 by scientists, physicians, and inventors came many stories of burns, hair loss, and worse in technical journals of the time. In February 1896, Professor John Daniel and Dr. William Lofland Dudley of Vanderbilt University reported hair loss after Dr. Dudley was X-rayed. A child who had been shot in the head was brought to the Vanderbilt laboratory in 1896. Before trying to find the bullet an experiment was attempted, for which Dudley "with his characteristic devotion to science"[31][32][33] volunteered. Daniel reported that 21 days after taking a picture of Dudley's skull (with an exposure time of one hour), he noticed a bald spot 2 inches (5.1 cm) in diameter on the part of his head nearest the X-ray tube: "A plate holder with the plates towards the side of the skull was fastened and a coin placed between the skull and the head. The tube was fastened at the other side at a distance of one-half inch from the hair."[34]

text: In August 1896 Dr. HD. Hawks, a graduate of Columbia College, suffered severe hand and chest burns from an x-ray demonstration. It was reported in Electrical Review and led to many other reports of problems associated with x-rays being sent in to the publication.[35] Many experimenters including Elihu Thomson at Edison's lab, William J. Morton, and Nikola Tesla also reported burns. Elihu Thomson deliberately exposed a finger to an x-ray tube over a period of time and suffered pain, swelling, and blistering.[36] Other effects were sometimes blamed for the damage including ultraviolet rays and (according to Tesla) ozone.[37] Many physicians claimed there were no effects from x-ray exposure at all.[36] On August 3, 1905 at San Francisco, California, Elizabeth Fleischman, American woman X-ray pioneer, died from complications as a result of her work with X-rays.[38][39][40]

text: 20th century and beyond[edit]

text: The many applications of X-rays immediately generated enormous interest. Workshops began making specialized versions of Crookes tubes for generating X-rays and these first-generation cold cathode or Crookes X-ray tubes were used until about 1920.

text: Crookes tubes were unreliable. They had to contain a small quantity of gas (invariably air) as a current will not flow in such a tube if they are fully evacuated. However, as time passed, the X-rays caused the glass to absorb the gas, causing the tube to generate "harder" X-rays until it soon stopped operating. Larger and more frequently used tubes were provided with devices for restoring the air, known as "softeners". These often took the form of a small side tube which contained a small piece of mica, a mineral that traps relatively large quantities of air within its structure. A small electrical heater heated the mica, causing it to release a small amount of air, thus restoring the tube's efficiency. However, the mica had a limited life, and the restoration process was difficult to control.

text: In 1904, John Ambrose Fleming invented the thermionic diode, the first kind of vacuum tube. This used a hot cathode that caused an electric current to flow in a vacuum. This idea was quickly applied to X-ray tubes, and hence heated-cathode X-ray tubes, called "Coolidge tubes", completely replaced the troublesome cold cathode tubes by about 1920.

text: In about 1906, the physicist Charles Barkla discovered that X-rays could be scattered by gases, and that each element had a characteristic X-ray spectrum. He won the 1917 Nobel Prize in Physics for this discovery.

text: In 1912, Max von Laue, Paul Knipping, and Walter Friedrich first observed the diffraction of X-rays by crystals. This discovery, along with the early work of Paul Peter Ewald, William Henry Bragg, and William Lawrence Bragg, gave birth to the field of X-ray crystallography.

text: The Coolidge X-ray tube was invented during the following year by William D. Coolidge. It made possible the continuous emissions of X-rays. X-ray tubes similar to this are still in use in 2012.

text: The use of X-rays for medical purposes (which developed into the field of radiation therapy) was pioneered by Major John Hall-Edwards in Birmingham, England. Then in 1908, he had to have his left arm amputated because of the spread of X-ray dermatitis on his arm.[41]

text: In 1914 Marie Curie developed radiological cars to support soldiers injured in World War I. The cars would allow for rapid X-ray imaging of wounded soldiers so battlefield surgeons could quickly and more accurately operate.[42]

text: From the 1920s through to the 1950s, x-ray machines were developed to assist in the fitting of shoes and were sold to commercial shoe stores.[43][44][45] Concerns regarding the impact of frequent or poorly controlled use were expressed in the 1950s,[46][47] leading to the practise's eventual end that decade.[48]

text: The X-ray microscope was developed during the 1950s.

text: The Chandra X-ray Observatory, launched on July 23, 1999, has been allowing the exploration of the very violent processes in the universe which produce X-rays. Unlike visible light, which gives a relatively stable view of the universe, the X-ray universe is unstable. It features stars being torn apart by black holes, galactic collisions, and novae, and neutron stars that build up layers of plasma that then explode into space.

text: An X-ray laser device was proposed as part of the Reagan Administration's Strategic Defense Initiative in the 1980s, but the only test of the device (a sort of laser "blaster" or death ray, powered by a thermonuclear explosion) gave inconclusive results. For technical and political reasons, the overall project (including the X-ray laser) was de-funded (though was later revived by the second Bush Administration as National Missile Defense using different technologies).

text: Phase-contrast X-ray imaging refers to a variety of techniques that use phase information of a coherent x-ray beam to image soft tissues. It has become an important method for visualizing cellular and histological structures in a wide range of biological and medical studies. There are several technologies being used for x-ray phase-contrast imaging, all utilizing different principles to convert phase variations in the x-rays emerging from an object into intensity variations.[49][50] These include propagation-based phase contrast,[51] talbot interferometry,[50] refraction-enhanced imaging,[52] and x-ray interferometry.[53] These methods provide higher contrast compared to normal absorption-contrast x-ray imaging, making it possible to see smaller details. A disadvantage is that these methods require more sophisticated equipment, such as synchrotron or microfocus x-ray sources, X-ray optics, and high resolution x-ray detectors.

text: Energy ranges[edit]

text: Soft and hard X-rays[edit]

text: X-rays with high photon energies (above 5–10 keV, below 0.2–0.1 nm wavelength) are called hard X-rays, while those with lower energy are called soft X-rays.[54] Due to their penetrating ability, hard X-rays are widely used to image the inside of objects, e.g., in medical radiography and airport security. The term X-ray is metonymically used to refer to a radiographic image produced using this method, in addition to the method itself. Since the wavelengths of hard X-rays are similar to the size of atoms they are also useful for determining crystal structures by X-ray crystallography. By contrast, soft X-rays are easily absorbed in air; the attenuation length of 600 eV (~2 nm) X-rays in water is less than 1 micrometer.[55]

text: Gamma rays[edit]

text: There is no consensus for a definition distinguishing between X-rays and gamma rays. One common practice is to distinguish between the two types of radiation based on their source: X-rays are emitted by electrons, while gamma rays are emitted by the atomic nucleus.[56][57][58][59] This definition has several problems: other processes also can generate these high-energy photons, or sometimes the method of generation is not known. One common alternative is to distinguish X- and gamma radiation on the basis of wavelength (or, equivalently, frequency or photon energy), with radiation shorter than some arbitrary wavelength, such as 10−11 m (0.1 Å), defined as gamma radiation.[60] This criterion assigns a photon to an unambiguous category, but is only possible if wavelength is known. (Some measurement techniques do not distinguish between detected wavelengths.) However, these two definitions often coincide since the electromagnetic radiation emitted by X-ray tubes generally has a longer wavelength and lower photon energy than the radiation emitted by radioactive nuclei.[56] Occasionally, one term or the other is used in specific contexts due to historical precedent, based on measurement (detection) technique, or based on their intended use rather than their wavelength or source. Thus, gamma-rays generated for medical and industrial uses, for example radiotherapy, in the ranges of 6–20 MeV, can in this context also be referred to as X-rays.[citation needed]

text: Properties[edit]

text: X-ray photons carry enough energy to ionize atoms and disrupt molecular bonds. This makes it a type of ionizing radiation, and therefore harmful to living tissue. A very high radiation dose over a short period of time causes radiation sickness, while lower doses can give an increased risk of radiation-induced cancer. In medical imaging this increased cancer risk is generally greatly outweighed by the benefits of the examination. The ionizing capability of X-rays can be utilized in cancer treatment to kill malignant cells using radiation therapy. It is also used for material characterization using X-ray spectroscopy.

text: Hard X-rays can traverse relatively thick objects without being much absorbed or scattered. For this reason, X-rays are widely used to image the inside of visually opaque objects. The most often seen applications are in medical radiography and airport security scanners, but similar techniques are also important in industry (e.g. industrial radiography and industrial CT scanning) and research (e.g. small animal CT). The penetration depth varies with several orders of magnitude over the X-ray spectrum. This allows the photon energy to be adjusted for the application so as to give sufficient transmission through the object and at the same time provide good contrast in the image.

text: X-rays have much shorter wavelengths than visible light, which makes it possible to probe structures much smaller than can be seen using a normal microscope. This property is used in X-ray microscopy to acquire high resolution images, and also in X-ray crystallography to determine the positions of atoms in crystals.

text: Interaction with matter[edit]

text: X-rays interact with matter in three main ways, through photoabsorption, Compton scattering, and Rayleigh scattering. The strength of these interactions depends on the energy of the X-rays and the elemental composition of the material, but not much on chemical properties, since the X-ray photon energy is much higher than chemical binding energies. Photoabsorption or photoelectric absorption is the dominant interaction mechanism in the soft X-ray regime and for the lower hard X-ray energies. At higher energies, Compton scattering dominates.

text: Photoelectric absorption[edit]

text: The probability of a photoelectric absorption per unit mass is approximately proportional to Z3/E3, where Z is the atomic number and E is the energy of the incident photon.[61] This rule is not valid close to inner shell electron binding energies where there are abrupt changes in interaction probability, so called absorption edges. However, the general trend of high absorption coefficients and thus short penetration depths for low photon energies and high atomic numbers is very strong. For soft tissue, photoabsorption dominates up to about 26 keV photon energy where Compton scattering takes over. For higher atomic number substances this limit is higher. The high amount of calcium (Z=20) in bones together with their high density is what makes them show up so clearly on medical radiographs.

text: A photoabsorbed photon transfers all its energy to the electron with which it interacts, thus ionizing the atom to which the electron was bound and producing a photoelectron that is likely to ionize more atoms in its path. An outer electron will fill the vacant electron position and produce either a characteristic photon[clarification needed] or an Auger electron. These effects can be used for elemental detection through X-ray spectroscopy or Auger electron spectroscopy.

text: Compton scattering[edit]

text: Compton scattering is the predominant interaction between X-rays and soft tissue in medical imaging.[62] Compton scattering is an inelastic scattering of the X-ray photon by an outer shell electron. Part of the energy of the photon is transferred to the scattering electron, thereby ionizing the atom and increasing the wavelength of the X-ray. The scattered photon can go in any direction, but a direction similar to the original direction is more likely, especially for high-energy X-rays. The probability for different scattering angles are described by the Klein–Nishina formula. The transferred energy can be directly obtained from the scattering angle from the conservation of energy and momentum.

text: Rayleigh scattering[edit]

text: Rayleigh scattering is the dominant elastic scattering mechanism in the X-ray regime.[63] Inelastic forward scattering gives rise to the refractive index, which for X-rays is only slightly below 1.[64]

text: Production[edit]

text: Whenever charged particles (electrons or ions) of sufficient energy hit a material, X-rays are produced.

text: Production by electrons[edit]

text:
Characteristic X-ray emission lines for some common anode materials.[65][66]

Anode
material
Atomic
number
Photon energy [keV]
Wavelength [nm]

Kα1
Kβ1
Kα1
Kβ1

W
74
59.3
67.2
0.0209
0.0184

Mo
42
17.5
19.6
0.0709
0.0632

Cu
29
8.05
8.91
0.154
0.139

Ag
47
22.2
24.9
0.0559
0.0497

Ga
31
9.25
10.26
0.134
0.121

In
49
24.2
27.3
0.0512
0.455

text: X-rays can be generated by an X-ray tube, a vacuum tube that uses a high voltage to accelerate the electrons released by a hot cathode to a high velocity. The high velocity electrons collide with a metal target, the anode, creating the X-rays.[67] In medical X-ray tubes the target is usually tungsten or a more crack-resistant alloy of rhenium (5%) and tungsten (95%), but sometimes molybdenum for more specialized applications, such as when softer X-rays are needed as in mammography. In crystallography, a copper target is most common, with cobalt often being used when fluorescence from iron content in the sample might otherwise present a problem.

text: The maximum energy of the produced X-ray photon is limited by the energy of the incident electron, which is equal to the voltage on the tube times the electron charge, so an 80 kV tube cannot create X-rays with an energy greater than 80 keV. When the electrons hit the target, X-rays are created by two different atomic processes:

text:
Characteristic X-ray emission (X-ray fluorescence): If the electron has enough energy it can knock an orbital electron out of the inner electron shell of a metal atom, and as a result electrons from higher energy levels then fill up the vacancy and X-ray photons are emitted. This process produces an emission spectrum of X-rays at a few discrete frequencies, sometimes referred to as the spectral lines. The spectral lines generated depend on the target (anode) element used and thus are called characteristic lines. Usually these are transitions from upper shells into K shell (called K lines), into L shell (called L lines) and so on.
Bremsstrahlung: This is radiation given off by the electrons as they are scattered by the strong electric field near the high-Z (proton number) nuclei. These X-rays have a continuous spectrum. The intensity of the X-rays increases linearly with decreasing frequency, from zero at the energy of the incident electrons, the voltage on the X-ray tube.

tag: ol

text: So the resulting output of a tube consists of a continuous bremsstrahlung spectrum falling off to zero at the tube voltage, plus several spikes at the characteristic lines. The voltages used in diagnostic X-ray tubes range from roughly 20 kV to 150 kV and thus the highest energies of the X-ray photons range from roughly 20 keV to 150 keV.[68]

text: Both of these X-ray production processes are inefficient, with a production efficiency of only about one percent, and thus most of the electric power consumed by the tube is released as waste heat. When producing a usable flux of X-rays, the X-ray tube must be designed to dissipate the excess heat.

text: Short nanosecond bursts of X-rays peaking at 15-keV in energy may be reliably produced by peeling pressure-sensitive adhesive tape from its backing in a moderate vacuum. This is likely to be the result of recombination of electrical charges produced by triboelectric charging. The intensity of X-ray triboluminescence is sufficient for it to be used as a source for X-ray imaging.[69]

text: A specialized source of X-rays which is becoming widely used in research is synchrotron radiation, which is generated by particle accelerators. Its unique features are X-ray outputs many orders of magnitude greater than those of X-ray tubes, wide X-ray spectra, excellent collimation, and linear polarization.[70]

text: Production by fast positive ions[edit]

text: X-rays can also be produced by fast protons or other positive ions. The proton-induced X-ray emission or particle-induced X-ray emission is widely used as an analytical procedure. For high energies, the production cross section is proportional to Z12Z2−4, where Z1 refers to the atomic number of the ion, Z2 to that of the target atom.[71] An overview of these cross sections is given in the same reference.

text: Production in lightning and laboratory discharges[edit]

text: X-rays are also produced in lightning accompanying terrestrial gamma-ray flashes. The underlying mechanism is the acceleration of electrons in lightning related electric fields and the subsequent production of photons through Bremsstrahlung.[72] This produces photons with energies of some few keV and several tens of MeV.[73] In laboratory discharges with a gap size of approximately 1 meter length and a peak voltage of 1 MV, X-rays with a characteristic energy of 160 keV are observed.[74] A possible explanation is the encounter of two streamers and the production of high-energy run-away electrons;[75] however, microscopic simulations have shown that the duration of electric field enhancement between two streamers is too short to produce a significantly number of run-away electrons.[76]

text: Detectors[edit]

text: X-ray detectors vary in shape and function depending on their purpose. Imaging detectors such as those used for radiography were originally based on photographic plates and later photographic film, but are now mostly replaced by various digital detector types such as image plates and flat panel detectors. For radiation protection direct exposure hazard is often evaluated using ionization chambers, while dosimeters are used to measure the radiation dose a person has been exposed to. X-ray spectra can be measured either by energy dispersive or wavelength dispersive spectrometers.

text: Medical uses[edit]

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text: Since Röntgen's discovery that X-rays can identify bone structures, X-rays have been used for medical imaging. The first medical use was less than a month after his paper on the subject.[29] Up to 2010, 5 billion medical imaging examinations had been conducted worldwide.[77] Radiation exposure from medical imaging in 2006 made up about 50% of total ionizing radiation exposure in the United States.[78]

text: Projectional radiographs[edit]

text: Projectional radiography is the practice of producing two-dimensional images using x-ray radiation. Bones contain much calcium, which due to its relatively high atomic number absorbs x-rays efficiently. This reduces the amount of X-rays reaching the detector in the shadow of the bones, making them clearly visible on the radiograph. The lungs and trapped gas also show up clearly because of lower absorption compared to tissue, while differences between tissue types are harder to see.

text: Projectional radiographs are useful in the detection of pathology of the skeletal system as well as for detecting some disease processes in soft tissue. Some notable examples are the very common chest X-ray, which can be used to identify lung diseases such as pneumonia, lung cancer, or pulmonary edema, and the abdominal x-ray, which can detect bowel (or intestinal) obstruction, free air (from visceral perforations) and free fluid (in ascites). X-rays may also be used to detect pathology such as gallstones (which are rarely radiopaque) or kidney stones which are often (but not always) visible. Traditional plain X-rays are less useful in the imaging of soft tissues such as the brain or muscle. One area where projectional radiographs are used extensively is in evaluating how an orthopedic implant, such as a knee, hip or shoulder replacement, is situated in the body with respect to the surrounding bone. This can be assessed in two dimensions from plain radiographs, or it can be assessed in three dimensions if a technique called '2D to 3D registration' is used. This technique purportedly negates projection errors associated with evaluating implant position from plain radiographs.[79][80]

text: Dental radiography is commonly used in the diagnoses of common oral problems, such as cavities.

text: In medical diagnostic applications, the low energy (soft) X-rays are unwanted, since they are totally absorbed by the body, increasing the radiation dose without contributing to the image. Hence, a thin metal sheet, often of aluminium, called an X-ray filter, is usually placed over the window of the X-ray tube, absorbing the low energy part in the spectrum. This is called hardening the beam since it shifts the center of the spectrum towards higher energy (or harder) x-rays.

text: To generate an image of the cardiovascular system, including the arteries and veins (angiography) an initial image is taken of the anatomical region of interest. A second image is then taken of the same region after an iodinated contrast agent has been injected into the blood vessels within this area. These two images are then digitally subtracted, leaving an image of only the iodinated contrast outlining the blood vessels. The radiologist or surgeon then compares the image obtained to normal anatomical images to determine whether there is any damage or blockage of the vessel.

text: Computed tomography[edit]

text: Computed tomography (CT scanning) is a medical imaging modality where tomographic images or slices of specific areas of the body are obtained from a large series of two-dimensional X-ray images taken in different directions.[81] These cross-sectional images can be combined into a three-dimensional image of the inside of the body and used for diagnostic and therapeutic purposes in various medical disciplines.

text: Fluoroscopy[edit]

text: Fluoroscopy is an imaging technique commonly used by physicians or radiation therapists to obtain real-time moving images of the internal structures of a patient through the use of a fluoroscope. In its simplest form, a fluoroscope consists of an X-ray source and a fluorescent screen, between which a patient is placed. However, modern fluoroscopes couple the screen to an X-ray image intensifier and CCD video camera allowing the images to be recorded and played on a monitor. This method may use a contrast material. Examples include cardiac catheterization (to examine for coronary artery blockages) and barium swallow (to examine for esophageal disorders and swallowing disorders).

text: Radiotherapy[edit]

text: The use of X-rays as a treatment is known as radiation therapy and is largely used for the management (including palliation) of cancer; it requires higher radiation doses than those received for imaging alone. X-rays beams are used for treating skin cancers using lower energy x-ray beams while higher energy beams are used for treating cancers within the body such as brain, lung, prostate, and breast.[82][83]

text: Adverse effects[edit]

text: Diagnostic X-rays (primarily from CT scans due to the large dose used) increase the risk of developmental problems and cancer in those exposed.[84][85][86] X-rays are classified as a carcinogen by both the World Health Organization's International Agency for Research on Cancer and the U.S. government.[77][87] It is estimated that 0.4% of current cancers in the United States are due to computed tomography (CT scans) performed in the past and that this may increase to as high as 1.5-2% with 2007 rates of CT usage.[88]

text: Experimental and epidemiological data currently do not support the proposition that there is a threshold dose of radiation below which there is no increased risk of cancer.[89] However, this is under increasing doubt.[90] It is estimated that the additional radiation will increase a person's cumulative risk of getting cancer by age 75 by 0.6–1.8%.[91] The amount of absorbed radiation depends upon the type of X-ray test and the body part involved.[92] CT and fluoroscopy entail higher doses of radiation than do plain X-rays.

text: To place the increased risk in perspective, a plain chest X-ray will expose a person to the same amount from background radiation that people are exposed to (depending upon location) every day over 10 days, while exposure from a dental X-ray is approximately equivalent to 1 day of environmental background radiation.[93] Each such X-ray would add less than 1 per 1,000,000 to the lifetime cancer risk. An abdominal or chest CT would be the equivalent to 2–3 years of background radiation to the whole body, or 4–5 years to the abdomen or chest, increasing the lifetime cancer risk between 1 per 1,000 to 1 per 10,000.[93] This is compared to the roughly 40% chance of a US citizen developing cancer during their lifetime.[94] For instance, the effective dose to the torso from a CT scan of the chest is about 5 mSv, and the absorbed dose is about 14 mGy.[95] A head CT scan (1.5mSv, 64mGy)[96] that is performed once with and once without contrast agent, would be equivalent to 40 years of background radiation to the head. Accurate estimation of effective doses due to CT is difficult with the estimation uncertainty range of about ±19% to ±32% for adult head scans depending upon the method used.[97]

text: The risk of radiation is greater to a fetus, so in pregnant patients, the benefits of the investigation (X-ray) should be balanced with the potential hazards to the fetus.[98][99] In the US, there are an estimated 62 million CT scans performed annually, including more than 4 million on children.[92] Avoiding unnecessary X-rays (especially CT scans) reduces radiation dose and any associated cancer risk.[100]

text: Medical X-rays are a significant source of man-made radiation exposure. In 1987, they accounted for 58% of exposure from man-made sources in the United States. Since man-made sources accounted for only 18% of the total radiation exposure, most of which came from natural sources (82%), medical X-rays only accounted for 10% of total American radiation exposure; medical procedures as a whole (including nuclear medicine) accounted for 14% of total radiation exposure. By 2006, however, medical procedures in the United States were contributing much more ionizing radiation than was the case in the early 1980s. In 2006, medical exposure constituted nearly half of the total radiation exposure of the U.S. population from all sources. The increase is traceable to the growth in the use of medical imaging procedures, in particular computed tomography (CT), and to the growth in the use of nuclear medicine.[78][101]

text: Dosage due to dental X-rays varies significantly depending on the procedure and the technology (film or digital). Depending on the procedure and the technology, a single dental X-ray of a human results in an exposure of 0.5 to 4 mrem. A full mouth series of X-rays may result in an exposure of up to 6 (digital) to 18 (film) mrem, for a yearly average of up to 40 mrem.[102][103][104][105][106][107][108]

text: Financial incentives have been shown to have a significant impact on X-ray use with doctors who are paid a separate fee for each X-ray providing more X-rays.[109]

text: Other uses[edit]

text: Other notable uses of X-rays include

text:
X-ray crystallography in which the pattern produced by the diffraction of X-rays through the closely spaced lattice of atoms in a crystal is recorded and then analysed to reveal the nature of that lattice. In the early 1990s, experiments were done in which layers a few atoms thick of two different materials were deposited in a Thue-Morse sequence. The resulting object was found to yield X-ray diffraction patterns.[110] A related technique, fiber diffraction, was used by Rosalind Franklin to discover the double helical structure of DNA.[111]
X-ray astronomy, which is an observational branch of astronomy, which deals with the study of X-ray emission from celestial objects.
X-ray microscopic analysis, which uses electromagnetic radiation in the soft X-ray band to produce images of very small objects.
X-ray fluorescence, a technique in which X-rays are generated within a specimen and detected. The outgoing energy of the X-ray can be used to identify the composition of the sample.
Industrial radiography uses X-rays for inspection of industrial parts, particularly welds.

text:
Authentication and quality control, X-ray is used for authentication and quality control of packaged items.
Industrial CT (computed tomography) is a process which uses X-ray equipment to produce three-dimensional representations of components both externally and internally. This is accomplished through computer processing of projection images of the scanned object in many directions.
Paintings are often X-rayed to reveal underdrawings and pentimenti, alterations in the course of painting or by later restorers. Many pigments such as lead white show well in radiographs.
X-ray spectromicroscopy has been used to analyse the reactions of pigments in paintings. For example, in analysing colour degradation in the paintings of van Gogh[113]
Airport security luggage scanners use X-rays for inspecting the interior of luggage for security threats before loading on aircraft.
Border control truck scanners use X-rays for inspecting the interior of trucks.

text:
X-ray art and fine art photography, artistic use of X-rays, for example the works by Stane Jagodič
X-ray hair removal, a method popular in the 1920s but now banned by the FDA.[114]
Shoe-fitting fluoroscopes were popularized in the 1920s, banned in the US in the 1960s, banned in the UK in the 1970s, and even later in continental Europe.
Roentgen stereophotogrammetry is used to track movement of bones based on the implantation of markers
X-ray photoelectron spectroscopy is a chemical analysis technique relying on the photoelectric effect, usually employed in surface science.
Radiation implosion is the use of high energy X-rays generated from a fission explosion (an A-bomb) to compress nuclear fuel to the point of fusion ignition (an H-bomb).

text: Visibility[edit]

text: While generally considered invisible to the human eye, in special circumstances X-rays can be visible. Brandes, in an experiment a short time after Röntgen's landmark 1895 paper, reported after dark adaptation and placing his eye close to an X-ray tube, seeing a faint "blue-gray" glow which seemed to originate within the eye itself.[115] Upon hearing this, Röntgen reviewed his record books and found he too had seen the effect. When placing an X-ray tube on the opposite side of a wooden door Röntgen had noted the same blue glow, seeming to emanate from the eye itself, but thought his observations to be spurious because he only saw the effect when he used one type of tube. Later he realized that the tube which had created the effect was the only one powerful enough to make the glow plainly visible and the experiment was thereafter readily repeatable. The knowledge that X-rays are actually faintly visible to the dark-adapted naked eye has largely been forgotten today; this is probably due to the desire not to repeat what would now be seen as a recklessly dangerous and potentially harmful experiment with ionizing radiation. It is not known what exact mechanism in the eye produces the visibility: it could be due to conventional detection (excitation of rhodopsin molecules in the retina), direct excitation of retinal nerve cells, or secondary detection via, for instance, X-ray induction of phosphorescence in the eyeball with conventional retinal detection of the secondarily produced visible light.

text: Though X-rays are otherwise invisible, it is possible to see the ionization of the air molecules if the intensity of the X-ray beam is high enough. The beamline from the wiggler at the ID11 at the European Synchrotron Radiation Facility is one example of such high intensity.[116]

text: Units of measure and exposure[edit]

text: The measure of X-rays ionizing ability is called the exposure:

text:
The coulomb per kilogram (C/kg) is the SI unit of ionizing radiation exposure, and it is the amount of radiation required to create one coulomb of charge of each polarity in one kilogram of matter.
The roentgen (R) is an obsolete traditional unit of exposure, which represented the amount of radiation required to create one electrostatic unit of charge of each polarity in one cubic centimeter of dry air. 1 roentgen= 2.58×10−4 C/kg.

text: However, the effect of ionizing radiation on matter (especially living tissue) is more closely related to the amount of energy deposited into them rather than the charge generated. This measure of energy absorbed is called the absorbed dose:

text:
The gray (Gy), which has units of (joules/kilogram), is the SI unit of absorbed dose, and it is the amount of radiation required to deposit one joule of energy in one kilogram of any kind of matter.
The rad is the (obsolete) corresponding traditional unit, equal to 10 millijoules of energy deposited per kilogram. 100 rad= 1 gray.

text: The equivalent dose is the measure of the biological effect of radiation on human tissue. For X-rays it is equal to the absorbed dose.

text:
The Roentgen equivalent man (rem) is the traditional unit of equivalent dose. For X-rays it is equal to the rad, or, in other words, 10 millijoules of energy deposited per kilogram. 100 rem = 1 Sv.
The sievert (Sv) is the SI unit of equivalent dose, and also of effective dose. For X-rays the "equivalent dose" is numerically equal to a Gray (Gy). 1 Sv= 1 Gy. For the "effective dose" of X-rays, it is usually not equal to the Gray (Gy).

text:
Radiation related quantities view ‧ talk ‧ edit

Quantity
Unit
Symbol
Derivation
Year
SI equivalence

Activity (A)
curie
Ci
3.7 × 1010 s−1
1953
3.7×1010 Bq

becquerel
Bq
s−1
1974
SI

rutherford
Rd
106 s−1
1946
1,000,000 Bq

Exposure (X)
röntgen
R
esu / 0.001293 g of air
1928
2.58 × 10−4 C/kg

Fluence (Φ)
(reciprocal area)

m−2
1962
SI

Absorbed dose (D)
erg

erg⋅g−1
1950
1.0 × 10−4 Gy

rad
rad
100 erg⋅g−1
1953
0.010 Gy

gray
Gy
J⋅kg−1
1974
SI

Dose equivalent (H)
röntgen equivalent man
rem
100 erg⋅g−1
1971
0.010 Sv

sievert
Sv
J⋅kg−1 × WR
1977
SI


document_title: Shameless (season 8)

question_text: who plays liam in season 8 of shameless

question_tokens: who plays liam in season 8 of shameless

root

text: Shameless (season 8)

text: Cast and characters[edit]

text: Main[edit]

text:
William H. Macy as Frank Gallagher[4]
Emmy Rossum as Fiona Gallagher[4]
Jeremy Allen White as Philip "Lip" Gallagher[5]
Ethan Cutkosky as Carl Gallagher
Shanola Hampton as Veronica Fisher[6]
Steve Howey as Kevin Ball[5]
Emma Kenney as Deborah "Debbie" Gallagher[5]
Cameron Monaghan as Ian Gallagher[7]
Isidora Goreshter as Svetlana Fisher

tag: ul

text: Special Guest[edit]

text: Dermot Mulroney as Sean Pierce

text: Recurring[edit]

text:
Christian Isaiah as Liam Gallagher[8]
Jim Hoffmaster as Kermit
Michael Patrick McGill as Tommy
Alan Rosenberg as Professor Youens
Ruby Modine as Sierra Morton[9]
Zack Pearlman as Neil[10]
Elliot Fletcher as Trevor
Alicia Coppola as Sue
Scott Michael Campbell as Brad
Levy Tran as Eddie
Jessica Szohr as Nessa Chabon[11]
Perry Mattfeld as Mel
David Brackett as Duran
Richard Flood as Ford[12]
Faran Tahir as Adeeb[13]
Raffi Barsoumian as Bahir
Sammi Hanratty as Kassidi

text: Episodes[edit]

text:
No.
overall
No. in
season
Title
Directed by
Written by
Original air date
U.S. viewers
(millions)

85
1
"We Become What We... Frank!"
Iain B. MacDonald
John Wells
November 5, 2017 (2017-11-05)
1.86[14]

Fiona begins renovating and selling apartments in her new building. Frank returns from the monastery and begins to apologize to everyone he has wronged in the past. Lip tries to get his drinking problem under control while also trying to win back Sierra. Debbie gets a new job and begins night school where she's learning to become a welder. Ian tries to win back the heart of Trevor by helping teens at the youth center. Carl begins selling the meth that Monica left him and his siblings before she passed away while also staying in shape for military school over the summer break. Liam is used by the faculty of his new school to show off the school's diversity for prospective parents. Kevin learns some disturbing news about his health and Veronica tries to take back the Alibi from Svetlana.

86
2
"Where's My Meth?"
Anthony Hemingway
Nancy M. Pimental
November 12, 2017 (2017-11-12)
1.37[15]

Fiona grapples with evicting someone from the apartment building. Frank finds a job for the first time and tries to be a respectable citizen. Lip tries to sabotage Sierra's relationship. Ian goes with Trevor to a chub bar in an effort to fix their relationship. Carl tries to sell Ian's portion of Monica's meth but makes a troubling discovery about her. Liam visits a rich friend's house and is astonished by the luxury that others have. Kevin is sent off to a cancer support group and finds people he can relate to, trying to be ready for the operation that is coming.

87
3
"God Bless Her Rotting Soul"
Michael Morris
Krista Vernoff
November 19, 2017 (2017-11-19)
1.34[16]

While Kevin's tumour is benign, he becomes obsessed with being healthy and, upon researching his genetics, discovers that he comes from an inbred community in Kentucky. Fiona's evicted tenant destroys her room so Fiona attempts to find a new renter but comes into conflict with Nessa's girlfriend, Mel. Neil breaks up with Debbie. Ian continues to struggle with Monica's death. Lip tries to help Professor Yeouens deal with his alcoholism. Frank, now going by Francis, remains committed to becoming a better person. Svetlana tries to sell the Alibi, forcing Veronica to visit her in prison and make a deal, resulting in her release and partial-ownership of the bar. Monica's partner threatens the Gallaghers and they dig up her body in order to retrieve the meth.

88
4
"Fuck Paying It Forward"
Regina King
Dominique Morisseau
November 26, 2017 (2017-11-26)
1.59[17]

Frank is helping as much as he can at Liam's school, and meets a potential love interest amongst the mothers. Fiona is furious when Sean, now clean and married, returns to try and make amends. Lip is sex-crazed, and ends up sleeping with his co-worker, Eddie (Levy Tran). Ian lets a shelter girl of Trevor's sleep over to help her out of a bad spot, and gets chewed out by Trevor for it, but later they make amends, and Ian promises to try and find a living situation for some of the shelter kids. Debbie has moved back in, and is sad to be missing Frannie's growing up because of work. Carl attempts to catch a junkie breaking into houses on the block. Another black child join Liam's school. Kevin and Veronica meet Kevin's family; Kev is overwrought with emotion, whereas Veronica fears his family is racist.

89
5
"The (Mis)Education of Liam Fergus Beircheart Gallagher"
Iain B. MacDonald
Sheila Callaghan
December 3, 2017 (2017-12-03)
1.51[18]

Fiona tries to raise the profile of the neighborhood; Ian helps Trevor raise money for a youth shelter; Carl loses his scholarship; Lip stands up to a friend; Frank teaches parents about the working class.

90
6
"Icarus Fell And Rusty Ate Him"
Zetna Fuentes
Mark Steilen
December 10, 2017 (2017-12-10)
1.52[19]

After she discovers one of her tenants dead, Fiona is forced to reflect on her own life, as the rift between her and Ian grows deeper. Meanwhile, Lip enlists Carl's help to search for his AA sponsor, Brad, after he started drinking again. After having sex with Duran, Debbie has a pregnancy scare and tries to get a morning-after pill. Frank enjoys having his first-ever credit card, while Kev and V are making discoveries about their sexualities.

91
7
"Occupy Fiona"
Iain B. MacDonald
Molly Smith Metzler
December 17, 2017 (2017-12-17)
1.58[20]

Ian keeps testing Fiona's patience, and starts a "Occupy Fiona" movement right to her front door. With the support of Brad, Lip tries to help Youens for his DUI trial, after the latter's fifth drunk driving. Meanwhile, a now unemployed Frank goes on a job hunt, while Debbie is facing a rude doctor at her own work. Carl gets close to Kassidi, one of his rehab clients, who comes up with a plan to get him easy money. An unsure Kev is learning how to seuxally dominate V.

92
8
"Frank's Northern Southern Express"
Emmy Rossum
Nancy M. Pimental
December 31, 2017 (2017-12-31)
TBD

Fiona considers moving into one of her apartments, while she tries to get closer to Ford. Frank starts an import-export business, by smuggling muslim people and drugs through the US-Canada border. Meanwhile, Lip interviews new AA sponsors, and discovers something about Charlie, Sierra's boyfriend. Ian confronts a pastor preaching gay conversion, as Carl tries to conciliate his job and Kassidi, his new problematic girlfriend. As she tries to find a new job and some money, Debbie thinks she is pregnant again. Kev starts showing his dominating side against Svetlana at work, to the pleasure of V.

93
9
"The Fugees"[21]
Jeffrey Reiner
Dominique Morisseau
January 7, 2018 (2018-01-07)
TBD

94
10
"Church of Gay Jesus"[22]
TBA
TBA
January 14, 2018 (2018-01-14)
TBD

95
11
"A Gallagher Pedicure"[23]
TBA
TBA
January 21, 2018 (2018-01-21)
TBD

96
12
"Sleepwalking"[24]
TBA
TBA
January 28, 2018 (2018-01-28)
TBD

tag: table

text: Ratings[edit]

text:
No.
Title
Air date
Rating/share
(18–49)
Viewers
(millions)
DVR
(18–49)
DVR viewers
(millions)
Total
(18–49)
Total viewers
(millions)

1
"We Become What We ... Frank!"
November 5, 2017
0.7
1.86[14]
0.5
1.16
1.2
3.02[25]

2
"Where's My Meth?"
November 12, 2017
0.5
1.37[15]
N/A
N/A
N/A
N/A

3
"God Bless Her Rotting Soul"
November 19, 2017
0.5
1.34[16]
N/A
N/A
N/A
N/A

4
"Fuck Paying It Forward"
November 26, 2017
0.6
1.59[17]
0.6
1.26
1.2
2.86[26]

5
"The (Mis)Education of Liam Fergus Beircheart
Gallagher"
December 3, 2017
0.6
1.51[18]
0.5
1.42
1.1
2.93[27]

6
"Icarus Fell And Rusty Ate Him"
December 10, 2017
0.5
1.52[19]
0.6
1.40
1.1
2.92[28]

7
"Occupy Fiona"
December 17, 2017
0.5
1.58[20]
TBD
TBD
TBD
TBD


document_title: The Life of Riley

question_text: where does the expression living the life of riley come from

text: The Life of Riley

text: Source of the title[edit]

text: Theories exist as to the origin, for example from James Whitcomb Riley's poems in the 1880s depicting the comforts of a prosperous home life,[3] but it could have an Irish origin: After the Reilly clan consolidated its hold on County Cavan, they minted their own money, which was accepted as legal tender even in England. These coins, called "O'Reillys" and "Reillys," became synonymous with a monied person, and a gentleman freely spending was therefore "living on his Reillys."

tag: p

text: Radio[edit]

text:
The Life of Riley (radio)

William Bendix as Chester A. Riley

Genre
Situation comedy

Running time
30 minutes

Country of origin
United States

Language(s)
English

Syndicates
ABC
NBC

TV adaptations
The Life of Riley

Starring
William Bendix
John Brown
Grace Coppin
Paula Winslowe

Announcer
Ken Niles
Ken Carpenter
Jimmy Wallington

Created by
Irving Brecher

Written by
Alan Lipscott
Reuben Ship

Produced by
Irving Brecher

Original release
January 16, 1944 (1944-01-16) – June 29, 1951 (1951-06-29)

Sponsored by
Prell Shampoo
Teel
Pabst Blue Ribbon
Dreft
American Meat Institute

text: An unrelated radio show with the name Life of Riley was a summer replacement show heard on CBS from April 12, 1941, to September 6, 1941. The CBS program starred Lionel Stander as J. Riley Farnsworth and had no real connection with the more famous series that followed a few years later.[4]

text: The radio program starring William Bendix as Riley initially aired on the Blue Network, later known as ABC, from January 16, 1944, to June 8, 1945. Then it moved to NBC, where it was broadcast from September 8, 1945, to June 29, 1951.

text: The supporting cast featured Paula Winslowe as Peg (Riley's wife) and as Riley's mother-in law; John Brown as undertaker "Digger" O'Dell and as Riley's co-worker Jim Gillis; Francis "Dink" Trout as Waldo Binny; Tommy Cook, Bobby Ellis and Scotty Beckett, each playing Junior during the show's run; Sharon Douglas playing Babs, Riley's daughter; and, in one episode, Henry Morgan voicing Riley's father. Alan Reed was a regular on the show as multiple characters, including Riley's boss (Mr. Stevenson) and Peg's father; Shirley Mitchell played Honeybee Gillis; and Hans Conried was Uncle Baxter.

text: Whereas Gillis gave Riley bad information that got him into trouble, Digger gave him good information that "helped him out of a hole," as he might have put it. Brown's lines as the undertaker were often repetitive, including puns based on his profession; but thanks to Brown's delivery, the audience loved him. The program was broadcast live with a studio audience, most of whom were not aware Brown played both characters. As a result, when Digger delivered his first line, it was usually greeted with howls of laughter and applause from surprised audience members.[citation needed]

text: The series was co-developed by the nonperforming Marx Brother turned agent Gummo. The American Meat Institute (1944–45), Procter & Gamble (Teel dentifrice and Prell shampoo) (1945–49), and Pabst Blue Ribbon beer (1949–51) took turns as the radio program's sponsor.[5]

text: Film[edit]

text: William Bendix starred in the 1949 film version of The Life of Riley directed by Irving Brecher. It earned $1.6 million in the US and Canada.[6]

text: This prevented him from starring in the TV series that began in 1949. He took over the starring role in the TV series' second run, which started in 1953. Bendix and Rosemary DeCamp (who starred as Riley's wife in Gleason's version of the TV series) repeated the roles when an hour-long radio adaptation of the feature film was presented on Lux Radio Theater in May 1950.

text: Television[edit]

text:
The Life of Riley (television)

John Brown as Digger with Jackie Gleason as Riley.

Genre
Situation comedy[7]

Starring
Jackie Gleason (1949-1950)
William Bendix (1953-1958)

Country of origin
United States

Original language(s)
English

No. of seasons
6

Production

Running time
30 minutes[7]

Release

Original network
NBC

Original release
October 4, 1949 – August 22, 1958

text: In 1948, NBC broadcast "two live television test programs based on the radio series."[8] The April 13 episode starred Herb Vigran as Riley, and the April 20 episode had Buddy Gray in the title role.[8][9]

text: Jackie Gleason[edit]

text: The show was adapted for television on NBC by the producer of the radio series, Irving Brecher. It was seen for single-season telecast from October 4, 1949, to March 28, 1950.

text: Originally, William Bendix was to have appeared on both radio and television, but Bendix's RKO Radio Pictures movie contract prevented him from appearing on the television version. Instead, Jackie Gleason starred, along with Rosemary DeCamp, replacing Paula Winslowe, as wife Peg, Gloria Winters as daughter Barbara (Babs), Lanny Rees as son Chester Jr. (Junior), and Sid Tomack as Jim Gillis, Riley's manipulative best buddy and next-door neighbor. John Brown returned as the morbid counseling undertaker Digby (Digger) O'Dell ("Cheerio, I'd better be... shoveling off"; "Business is a little dead tonight"). Television's first Life of Riley won television's first Emmy (for "Best Film Made For and Shown on Television"). However, it came to an end after 26 episodes, not because of low ratings or a desire by Gleason to leave the series, but because Irving Brecher and sponsor Pabst Brewing Company reached an impasse on extending the series for a full 39-week season. Groucho Marx received a credit for "story."

text: Episode List:

text:
Episode 1: Tonsils
Episode 2: Babs and Simon Step Out
Episode 3: Egbert's Chemistry Set
Episode 4: The French Professor
Episode 5: The Nervous Breakdown
Episode 6: Assistant Manager with Mary Treen
Episode 7: Riley's Birthday Gift
Episode 8: Riley, Gills, and Vanderhopper, Inc.
Episode 9: Junior Falls for Teacher
Episode 10: Night School
Episode 11: Prom Dress
Episode 12: Junior's Birthday Present
Episode 13: The Border
Episode 14: Peg's Birthday
Episode 15: Junior Drops Out
Episode 16: Riley's Firstborn
Episode 17: Insurance
Episode 18: The Gambler
Episode 19: Acting Lessons
Episode 20: Valentine's Day
Episode 21: Home Sweet Home
Episode 22: South American Job
Episode 23: Riley's Quarrel
Episode 24: Junior and the Bully
Episode 25: The Banned Book
Episode 26: Five Dollar Bill

text: William Bendix[edit]

text: This section possibly contains original research. Please improve it by verifying the claims made and adding inline citations. Statements consisting only of original research should be removed. (August 2013) (Learn how and when to remove this template message)

text: The second TV series ran for six seasons, from January 2, 1953, to May 23, 1958. It was produced by Tom McKnight for NBC and featured William Bendix. He was supported by Marjorie Reynolds, replacing both Paula Winslowe and Rosemary DeCamp, as wife Peg; Tom D'Andrea as schemer buddy Jim Gillis; Gloria Blondell (sister of Joan Blondell) as Gillis' wife, Honeybee; Lugene Sanders as daughter Babs; and Wesley Morgan as son Junior. This Life of Riley series with Bendix was a ratings hit, ranking at #16 in its first season, with four of its six seasons in the top 30, and ran for a total of 217 episodes. It then went into syndicated reruns.

text: In all of the show's incarnations, the comedic plotlines centered around Riley himself, a gullible and occasionally clumsy (but big-hearted) man, and the doings and undoings of his family. Riley's penchant for turning mere trouble into near-disaster through his well-intentioned bumbling was often aided or instigated by his arch best friend/next-door neighbor, Gillis.

text: Legacy[edit]

text: In several ways, Riley was a prototype for later blue-collar sitcom protagonists such as blustery, get-rich-quick schemer Ralph Kramden (played, perhaps not coincidentally, by Jackie Gleason) and his animated stone-age counterpart Fred Flintstone; blustery bigot Archie Bunker; benign, bighearted Dan Conner; and King of Queens Doug Heffernan. Perhaps the greatest tribute to The Life of Riley was paid by Married... with Children: Ed O'Neill's language and manner of speaking as Al Bundy are remarkably similar to Bendix's, and Al's wife, like Riley's, is named Peg. Bendix's Riley, especially, was perhaps too guileless to be the true prototype for this group, but for making blue-collar characters as operable on television as on radio or in film, Chester Riley earned his place in broadcasting history.[10]

text: The latter portion of the fifth season, broadcast between April and June 1957, was filmed and originally broadcast in color, although only black-and-white film prints of those episodes were syndicated. For the final season, filming reverted to black-and-white.

text: Sponsors of the TV show included Pabst Blue Ribbon Beer (1949–50), Gulf Oil (1953–58) and Lever Brothers (1957–58).

text:
Chester and Peg Riley

Riley and Gillis.

William Bendix and Sterling Holloway, 1957.

text: A comic book adaptation of the show was produced by Dell Comics in 1958 as part of their Four Color series of one-shots.


document_title: Voting age

question_text: what is the legal age to vote in canada

question_tokens: what is the legal age to vote in canada

text: Voting age

text: History[edit]

text: Before the Second World War, the voting age in almost all countries was 21 years or higher. Czechoslovakia was the first to reduce the voting age to 20 years in 1946, and by 1968 a total of 17 countries had lowered their voting age.[1] Many countries, particularly in Western Europe, reduced their voting ages to 18 years during the 1970s, starting with the United Kingdom (1970),[2] with the United States (26th Amendment) (1971), Canada, Germany (1972), Australia (1974), France (1974) and others following soon afterwards. By the end of the 20th century, 18 had become by far the most common voting age. However, a few countries maintain a voting age of 20 years or higher. It was argued that 18-year-old men could be drafted to go to war, and many people felt they should be able to vote at the age of 18.[3]

text: In the late 20th and early 21st centuries voting ages were lowered to 18 in India, Switzerland, Austria and Morocco. Japan was due to make the change to 18 in 2016.[4] A dispute is continuing in the Maldives.[5][6]

text: Debate on lowering voting age to 16[edit]

text: Around the year 2000 a number of countries began to consider whether the voting age ought to be reduced further, with arguments most often being made in favour of a reduction to 16. The earliest moves came during the 1990s, when the voting age for municipal elections in some States of Germany was lowered to 16. Lower Saxony was the first state to make such a reduction, in 1995, and four other states did likewise.[7]

text: Arguments against lowering the voting age to sixteen include lack of political maturity and arguments for include encouraging interest in politics in young people.

text: During the 2000s several proposals for a reduced voting age were put forward in U.S. states, including California, Florida and Alaska,[8] but none was successful. A national reduction was proposed in 2005 in Canada[9] and in the Australian state of New South Wales,[10] but these proposals were not adopted. In May 2009, Danish Member of Parliament Mogens Jensen presented an initiative to the Parliamentary Assembly of the Council of Europe in Strasbourg to lower the voting age in Europe to 16.[11]

text: Austria[edit]

text: In 2007, Austria became the first member of the European Union to adopt a voting age of 16 for most purposes.[12] The voting age had been reduced in Austria from 19 to 18 at all levels in 1992. At that time a voting age of 16 was proposed by the Green Party, but was not adopted.[13]

text: The voting age for municipal elections in some states was lowered to 16 shortly after 2000.[7] Three states had made the reduction by 2003 (Burgenland, Carinthia and Styria),[7] and in May 2003 Vienna became the fourth.[14] Salzburg followed suit,[15][16] and so by the start of 2005 the total had reached at least five states out of nine.[17] As a consequence of state law, reduction of the municipal voting age in the states of Burgenland, Salzburg and Vienna resulted in the reduction of the regional voting age in those states as well.[16]

text: After the 2006 election, the winning SPÖ-ÖVP coalition announced on 12 January 2007 that one of its policies would be the reduction of the voting age to 16 for elections in all states and at all levels in Austria.[18] The policy was set in motion by a Government announcement on 14 March,[19] and a bill proposing an amendment to the Constitution was presented to the legislature on 2 May.[20][21] On 5 June the National Council approved the proposal following a recommendation from its Constitution Committee.[12][13][22] During the passage of the bill through the chamber relatively little opposition was raised to the reduction, with four out of five parties explicitly supporting it; indeed, there was some dispute over which party had been the first to suggest the idea. Greater controversy surrounded the other provisions of the bill concerning the Briefwahl, or postal vote, and the extension of the legislative period for the National Council from four to five years.[13] A further uncontroversial inclusion was a reduction in the candidacy age from 19 to 18. The Federal Council approved the Bill on 21 June, with no party voting against it.[23] The voting age was reduced when the Bill's provisions came into force on 1 July 2007.[24] Austria thus became the first member of the European Union, and the first of the developed world democracies, to adopt a voting age of 16 for all purposes.[12] Lowering the voting age encouraged political interest in young people in Austria. More sixteen and seventeen year olds voted than eighteen to twenty-one year olds in Austria.

text: Brazil[edit]

text: Brazil lowered the voting age from 18 to 16 in the 1988 constitution. The presidential election of 1989 was the first with the lower voting age. People between the ages 18 and 70 are required to vote.

text: Malta[edit]

text: On 20 November 2013, Malta lowered the voting age from 18 to 16 for local elections starting from 2015. The proposal had wide support from both the government and opposition, social scientists and youth organizations.

text: On Monday 29 January 2018, the Maltese Parliament will be debating to lower the voting age to 16 for General Elections, European Parliament Elections and referenda.

text: On Monday, 5 March 2018, the Maltese Parliament unanimously voted in favour of ammeding the constitution, lowering the official voting age from 18 to 16, making Malta the second state in the EU to lower its voting age to 16.[25]

text: United Kingdom[edit]

text: The Representation of the People Act 1969 lowered the voting age from 21 to 18, with effect from 1970 and remained in force until the Scottish Independence Referendum Act 2013 which allowed 16 year olds to vote for the first time, but only in Scotland and only in that particular referendum. The Scottish Parliament reduced the voting age to 16 for its own and Scottish local elections in 2015.[26]

text: Men in military service who turned 19 during the first world war were entitled to vote in 1918 irrespective of their age as part of the Representation of the People Act 1918 which also allowed some women over the age of 30 to vote. The Representation of the People (Equal Franchise) Act 1928[27] brought the voting age for women down to 21.

text: The reduction of the voting age to 16 in the United Kingdom was first given serious consideration on 15 December 1999, when the House of Commons considered in Committee an amendment proposed by Simon Hughes to the Representation of the People Bill.[28] This was the first time the reduction of a voting age below 18 had ever been put to a vote in the Commons.[29] The Government opposed the amendment, and it was defeated by 434 votes to 36.[29]

text: The Votes at 16 coalition, a group of political and charitable organisations supporting a reduction of the voting age to 16, was launched on 29 January 2003.[30] At that time a Private Member's Bill was also proposed in the House of Lords by Lord Lucas, and received a Second Reading on 9 January.[31]

text: In 2004, the UK Electoral Commission conducted a major consultation on the subject of the voting and candidacy ages, and received a significant response. In its conclusions it recommended that the voting age remain at 18.[32] On 29 November 2005 the House of Commons voted 136-128 (on a free vote) against a Private Member's Bill for a reduction in the voting age to 16 proposed by Liberal Democrat MP Stephen Williams. Parliament chose not to include a provision reducing the voting age in the Electoral Administration Act during its passage in 2006.

text: On 27 February 2006, the report of the Power Inquiry called for a reduction of the voting age, and of the candidacy age for the House of Commons, to 16.[33] On the same day the Chancellor of the Exchequer, Gordon Brown, indicated in an article in The Guardian that he favoured a reduction provided it was made concurrently with effective citizenship education.[34]

text: The UK Ministry of Justice published on 3 July 2007 a Green Paper entitled The Governance of Britain, in which it proposed the establishment of a "Youth Citizenship Commission".[35] The Commission would examine the case for lowering the voting age. On launching the Paper in the House of Commons, PM Gordon Brown said: "Although the voting age has been 18 since 1969, it is right, as part of that debate, to examine, and hear from young people themselves, whether lowering that age would increase participation."[36]

text: The Scottish National Party's conference voted unanimously on 27 October 2007 for a policy of reducing the voting age to 16, as well as in favour of a campaign for the necessary power to be devolved to the Scottish Parliament.[37]

text: During the Youth Parliament debates of 30 October 2009 in the House of Commons, Votes at 16 was debated and young people of that age group voted for it overwhelmingly as a campaign priority. Since that debate the issue has been raised in Prime Minister's Questions and has also gained the widespread support of the major political parties.[citation needed]

text: In April 2015, Labour announced that it would support the policy if it won an overall majority in the 2015 general election.[38]

text: There was some criticism about not reducing the voting age to 16 years for the referendum on the membership in the European Union in 2016.[39][40]

text: Scotland[edit]

text: In September 2011, it was announced that the voting age was likely to be reduced from 18 to 16 for the Scottish independence referendum.[41] This was approved by the Scottish Parliament in June 2013.[42]

text: In June 2015, the Scottish Parliament voted unanimously to reduce the voting age to 16 for Scottish Parliament elections and Scottish local government elections.[26]

text: Crown dependencies[edit]

text: Moves to lower the voting age to 16 were successful in each of the three British Crown dependencies from 2006 to 2008. The Isle of Man was the first to amend its law, when in July 2006 it reduced the voting age to 16 for its general elections, with the House of Keys approving the move by 19 votes to 4.[43]

text: Jersey followed suit on 4 July 2007, when it approved in principle a reduction of the voting age to 16. The States of Jersey voted narrowly in favour, by 25 votes to 21,[44] and the legislative amendments were adopted on 26 September.[45] The law was sanctioned by Order in Council on 12 December,[46][47] and was brought into force on 1 April, in time for the general elections in late 2008.[48][49]

text: On 31 October 2007, a proposal[50][51] for a reduction made by the House Committee of the States of Guernsey, and approved by the States' Policy Committee, was adopted by the assembly by 30 votes to 15.[51][52] An Order in Council sanctioning the law was made on 12 December,[46] and it was registered at the Court of Guernsey on 19 December. It came into force immediately, and the voting age was accordingly reduced in time for the Guernsey general election, 2008.[53]

text: Alderney and Sark, each part of the Bailiwick of Guernsey, have autonomy in deciding the question. Both have yet to favour a reduction to 16.

text: United States[edit]

text: In the United States, the debate about lowering voting age from 21 to 18 began during World War II and intensified during the Vietnam War, when most of those subjected to the draft were too young to vote, and the image of young men being forced to risk their lives in the military without the privileges of voting successfully pressured legislators to lower the voting age nationally and in many states. By 1968, several states had lowered the voting age below 21 years: Alaska and Hawaii's minimum age was 20, Kentucky's was 19, and Georgia's was 18.[54] In 1970, the Supreme Court in Oregon v. Mitchell ruled that Congress had the right to regulate the minimum voting age in federal elections; however, not at local and state level.

text: The 26th Amendment (passed and ratified in 1971)[55] set the voting age for federal and state elections at 18 years, but does not prevent states from establishing a lower voting age.[56] Except for the express limitations provided for in Amendments XIV, XV, XIX and XXVI, voter qualifications for House and Senate elections are largely delegated to the States under Article I, Section 2 and Amendment XVII of the United States Constitution, which respectively state that "The House of Representatives shall be composed of Members chosen every second Year by the People of the several States, and the Electors in each State shall have the Qualifications requisite for Electors of the most numerous Branch of the State Legislature." and "The Senate of the United States shall be composed of two Senators from each State, elected by the people thereof, for six years; and each Senator shall have one vote. The electors in each State shall have the qualifications requisite for electors of the most numerous branch of the State legislatures."[57]

text: 21 states permit 17-year-olds to vote in primary elections and caucuses if they will be 18 by election day: Alaska, Connecticut, Hawaii, Illinois, Indiana, Iowa, Kansas, Kentucky, Maine, Maryland, Mississippi, Nebraska, Nevada, New Mexico,[58] North Dakota, North Carolina, Ohio, Oregon, Virginia, Vermont, and Washington. Alaska, Kansas, North Dakota and Washington allow 17-year-olds to participate in Democrat caucuses, but not in the Republican caucus. Minnesota allows 17-year-olds to participate in presidential caucuses, but may not vote in primary elections for other offices.[59] New Hampshire allows anyone who will be 18 years old by the time of next election to register, meaning some 17-year-olds can register to vote in this state.[60]

text: Currently, the Maine Green Independent Party, the state branch of the Green Party of the United States, calls for the lowering of the voting age to 17.[61] Youth suffrage appears to be gaining ground in Massachusetts; three of the four Democratic United States Senate candidates in 2010 supported lowering the voting age.[62]

text: In 2013, the City of Takoma Park, Maryland became the first place in the United States to lower its voting age to 16, for local (but not general) elections and referendums.[63][64]

text: Iran[edit]

text: Iran had been unique in awarding suffrage at 15, but raised the age to 18 in January 2007 despite the opposition of the Government.[65] In May 2007 the Iranian Cabinet proposed a bill to reverse the increase.[66][67]

text: Switzerland[edit]

text: On 6 May 2007, the Swiss Canton of Glarus reduced the voting age from 18 to 16 for cantonal and local elections.[68][69]

text: New Zealand[edit]

text: The New Zealand Green Party MP Sue Bradford announced on 21 June 2007 that she intended to introduce her Civics Education and Voting Age Bill on the next occasion upon which a place became available for the consideration of Members' Bills.[70] When this happened on 25 July Bradford abandoned the idea, citing an adverse public reaction.[71] The Bill would have sought to reduce the voting age to 16 in New Zealand and make civics education part of the compulsory curriculum in schools.

text: Venezuela[edit]

text: A request to lower the voting age to 16 was made during consideration of revisions to the Constitution of Venezuela in 2007. Cilia Flores, president of the National Assembly, announced that the Mixed Committee for Constitutional Reform had found the idea acceptable.[72] Following approval in the legislature[73] the amendment formed part of the package of constitutional proposals, and was defeated in the 2007 referendum.

text: Australia[edit]

text: A report suggesting that consideration be given to reducing the voting age to 16 in the Australian Capital Territory in Canberra, Australia was tabled in the territorial legislature on 26 September 2007 and defeated.[74]

text: In 2015, federal Opposition Leader Bill Shorten said that the voting age should be lowered to 16.[75]

text: Luxembourg[edit]

text: Luxembourg has compulsory voting from the age of 18. A proposal by the government to introduce optional voting for those aged 16 and 17 was rejected by 81% of voters in a June 2015 referendum.

text: Voting ages around the world[edit]

text: Eighteen is the most common voting age, with a small minority of countries differing from this rule. Those with a national minimum age of 17 include East Timor, Greece, Indonesia, North Korea, South Sudan and Sudan. The minimum age is 16 in Argentina, Austria, Brazil, Cuba, Ecuador, Nicaragua and the Isle of Man, Jersey and Guernsey (three self-governing British Crown Dependencies). People aged 16–18 can vote in Bosnia, Serbia and Montenegro if employed. The highest minimum voting age is 21 in several nations. Some countries have variable provision for the minimum voting age, whereby a lower age is set for eligibility to vote in state, regional or municipal elections.

text: The only known maximum voting age is in the Holy See, where the franchise for electing a new Pope is restricted to Cardinals under the age of 80.

text: Alphabetical list of countries[edit]

text: The following is an alphabetical list of voting ages in the various countries of the world.[76]

text: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

text: A[edit]

text:
Afghanistan: 18
Albania: 18
Algeria: 18
American Samoa: 18
Andorra: 18
Angola: 18
Anguilla: 18
Antigua and Barbuda: 18
Argentina: 16, 16 to 18 and 70+ optional.
Armenia: 18
Aruba:18
Australia: 18, voting is compulsory
Austria: 16[24]
Azerbaijan: 18

text: B[edit]

text:
Bahamas: 18
Bahrain: 20[77]
Bangladesh: 18
Barbados: 18
Belarus: 18
Belgium: 18 (compulsory)
Belize: 18
Benin: 18
Bermuda: 18
Bhutan: 18
Bolivia: 18, universal and compulsory
Bosnia and Herzegovina: 18, 16 if employed
Botswana: 18
Brazil: 16, compulsory for 18 to 70; optional for illiterate citizens.
British Virgin Islands: 18
Brunei: 18 (village elections only)
Bulgaria: 18
Burkina Faso: 18
Burundi: 18

text: C[edit]

text:
Cambodia: 18
Cameroon: 21
Canada: 18
Cape Verde: 18
Cayman Islands: 18
Central African Republic: 18
Chad: 18
Chile: 18
China: 18
Cocos (Keeling) Islands: 18
Colombia: 18
Comoros: 18
Democratic Republic of the Congo: 18
Republic of the Congo: 18
Cook Islands: 18
Costa Rica: 18
Côte d'Ivoire: 18
Croatia: 18
Cuba: 16
Curaçao: 18
Cyprus: 18
Czech Republic: 18

text: D[edit]

text:
Denmark: 18
Djibouti: 18
Dominica: 18
Dominican Republic: 18, compulsory; married persons regardless of age (members of the armed forces and national police cannot vote)

text: E[edit]

text:
East Timor: 17
Ecuador: 16; universal, compulsory for literate persons ages 18–65, optional for other eligible voters
Egypt: 18
El Salvador: 18
England: 18
Equatorial Guinea: 18
Eritrea: 18
Estonia: 18; 16 for local elections
Ethiopia: 17
European Union: 18

text: F[edit]

text:
Falkland Islands: 18
Faroe Islands: 18
Fiji: 18, as of 2013 Constitution
Finland: 18
France: 18
French Polynesia: 18

text: G[edit]

text:
Gabon: 18
Gambia: 18
Georgia: 18
Germany: 18

Voting age 16 for state elections:  Brandenburg,  Bremen,  Hamburg and  Schleswig-Holstein.
Voting age 16 for municipal elections:  Baden-Württemberg,  Berlin,  Brandenburg,  Bremen,  Hamburg,  Mecklenburg-Vorpommern,  Lower Saxony,  North Rhine-Westphalia,  Saxony-Anhalt and  Schleswig-Holstein.[78]

Ghana: 18
Gibraltar: 18; universal, plus other British citizens who have been residents six months or more
Greece: 17 from 3 August 2016 onwards,[79] was 18 before 3 August 2016
Greenland: 18
Grenada: 18
Guadeloupe: 18
Guam: 18; US citizens, but do not vote in US presidential elections
Guatemala: 18; active-duty members of the armed forces may not vote and are restricted to their barracks on election day.
Guernsey: 16[80]
Guinea: 18
Guinea-Bissau: 18
Guyana: 18

text: H[edit]

text:
Haiti: 18
Honduras: 18
Hong Kong: direct election 18 years of age; universal for permanent residents living in the territory of Hong Kong for the past seven years; indirect election limited to about 220,000 members of functional constituencies and a 1,200-member election committee drawn from broad regional groupings, municipal organizations, and central government bodies
Hungary: 18

text: I[edit]

text:
Iceland: 18
India: 18
Indonesia: 17; no threshold for married persons, except for the military and police
Iran: 18 (changed from 15 to 18 in 2007, returned to 15 in 2009 and returned to 18 in 2011)[65][81][82][83]
Iraq: 18
Ireland: 18
Isle of Man: 16
Israel: 18 (17 for municipal elections)
Italy: 18 (25 for Senate elections)

text: J[edit]

text:
Jamaica: 18
Japan: 18 (changed from 20 in 2016)[4]
Jersey: 16
Jordan: 18

text: K[edit]

text:
Kazakhstan: 18
Kenya: 18
Kiribati: 18
North Korea: 17; members of the military have the right to vote, regardless of age[84]
South Korea: 19
Kosovo (disputed): 18
Kuwait: 21 for those not in the military or police forces; all voters must have been citizens for 20 years; current proposal for reduction to 18[85]
Kyrgyzstan: 18

text: L[edit]

text:
Laos: 18
Latvia: 18
Lebanon: 21. Attempt to amend to 18 on 22 February 2010 failed to pass.[86]
Lesotho: 18
Liberia: 18
Libya: 18
Liechtenstein: 18
Lithuania: 18
Luxembourg: 18, compulsory until the age of 75. A proposal to lower the voting age to 16 was rejected in 2015 in a nationwide referendum (81% "no"-votes)

text: M[edit]

text:
Macau: direct election 18 years of age, universal for permanent residents living in Macau for the past seven years; indirect election limited to organizations registered as "corporate voters" (973 are currently registered) and a 300-member Election Committee drawn from broad regional groupings, municipal organizations, and central government bodies
Republic of Macedonia: 18
Madagascar: 18
Malawi: 18
Malaysia: 21
Maldives: 18
Mali: 18
Malta: 16
Marshall Islands: 18
Martinique: 18
Mauritania: 18
Mauritius: 18
Mayotte: 18
Mexico: 18
Federated States of Micronesia: 18
Moldova: 18
Monaco: 18
Mongolia: 18
Montenegro: 18
Montserrat: 18
Morocco: 18
Mozambique: 18
Myanmar (Burma): 18

text: N[edit]

text:
Namibia: 18
Nauru: 20
Nepal: 18
Netherlands: 18
New Caledonia: 18
New Zealand: 18
Nicaragua: 16
Niger: 18
Nigeria: 18
Niue: 18
Norfolk Island: 18
Northern Mariana Islands: 18; indigenous inhabitants are US citizens but do not vote in US presidential elections
Norway: 18; however, persons 17 years of age are permitted to vote in parliamentary elections if they will be 18 years of age in the year the election is held.

text: O[edit]

text: Oman: 21, except for members of the military and police.

text: P[edit]

text:
Pakistan: 18; joint electorates and reserved parliamentary seats for women and non-Muslims
Palau: 18
Panama: 18
Papua New Guinea: 18
Paraguay: 18; universal and compulsory until the age of 75
Peru: 18; universal and compulsory until the age of 70; (members of the military and national police could not vote until a Constitutional Reform in 2005[87])
Philippines: 18

For youth councils: 18 to 30; previously from 15 to 18. Incumbents are allowed to keep their positions if they surpass the legal age.

Pitcairn Islands: 18; universal with three years' residency
Poland: 18
Portugal: 18
Puerto Rico: 18; island residents are US citizens but do not vote in US presidential elections.

text: Q[edit]

text: Qatar: 18

text: R[edit]

text:
Réunion: 18
Romania: 18
Russia: 18
Rwanda: 18

text: S[edit]

text:
Saint Helena: 18
Saint Kitts and Nevis: 18
Saint Lucia: 18
Saint Pierre and Miquelon: 18
Saint Vincent and the Grenadines: 18
Samoa: 21
San Marino: 18
São Tomé and Príncipe: 18
Saudi Arabia: 18
Scotland: 16
Senegal: 18
Serbia: 18[88]
Seychelles: 18[89]
Sierra Leone: 18
Singapore: 21
Sint Maarten: 18
Slovakia: 18
Slovenia: 18
Solomon Islands: 21
Somalia: 18
South Africa: 18
South Sudan: 17
Spain: 18 (16 only for Catalonia's 9N Referendum)
Sri Lanka: 18
Sudan: 17
Suriname: 18
Swaziland: 18
Sweden: 18
Switzerland: 18 (16 for cantonal and municipal elections in the canton of Glarus[68][69] [1/26])
Syria: 18

text: T[edit]

text:
Taiwan (Republic of China): 18
Tajikistan: 18
Tanzania: 18
Thailand: 18 (being a Thai citizen since birth, or at least 5 years)
Togo: 18
Tokelau: 21
Tonga: 21
Trinidad and Tobago: 18
Tunisia: 18 (with some exceptions)[90]
Turkey: 18
Turkmenistan: 18
Turks and Caicos Islands: 18
Tuvalu: 18

text: U[edit]

text:
Uganda: 18
Ukraine: 18[91]
United Arab Emirates: none[92] but at least 25 (the minimum age is decided by the ruler of each Emirate and may vary from one Emirate to another)[93]
United Kingdom: 18 (16 for the Scottish independence referendum, Scottish Parliament elections and Scottish local government elections.[26])
United States: 18; however, in many states, persons 17 years of age are permitted to vote in primary elections if they will be 18 years of age on or before the day of the general election.
Uruguay: 18
Uzbekistan: 18[94]

text: V[edit]

text:
Vanuatu: 18
Venezuela: 18
Vietnam: 18
Virgin Islands of the United States: 18; island residents are U.S. citizens but do not vote in U.S. presidential elections.

text: W[edit]

text:
Wallis and Futuna: 18
Western Sahara: none (18 for residents of Moroccan-controlled Western Sahara in Moroccan elections) [92]

text: Y[edit]

text: Yemen: 18

text: Z[edit]

text:
Zambia: 18
Zimbabwe: 18

text: Chronology of lowering the voting age to 18[edit]

text: The following is a chronological list of the dates upon which countries lowered the voting age to 18; unless otherwise indicated, the reduction was from 21. In some cases the age was lowered decrementally, and so the "staging points" are also given. Some information is also included on the relevant legal instruments involved.

text:
Turkey: 20 April 1924 (Previously 25 per the 1876 constitution, reduced to 18 with the 1924 constitution. It was again raised to 22 on 5 December 1934 while granting full women's suffrage, and gradually lowered to 21 in 1961, 20 in 1987 and 18 in 1995)[95][96]
Czechoslovakia: 1946
Poland: 1952[citation needed]
South Africa: 1958 (white voters only; Electoral Law Amendment Act, 1958)[97]
United Kingdom: 1 January 1970 (Representation of the People Act 1969)
Canada: 26 June 1970[98][99] (federal elections, amendment to Canada Elections Act)

text:
Germany: 1970 [104]
Netherlands: 1971 (previous reduction from 23 to 21 in 1965)
United States: 1 July 1971, per the Twenty-sixth Amendment. Previously reduced on 1 January 1971 by the Voting Rights Act Amendments 1970, ss. 302, 305[105] (Prior reductions: Georgia in August 1943,[106] Kentucky in 1955,[107] Guam in 1954[108] and American Samoa in 1965.[108])
Finland: 1972 (from 20; previous reductions were 24 to 21 in 1944 and 21 to 20 in 1968/1969)[109][110]
Sweden: 1972 (from 20) [111]
Ireland: 5 January 1973 (4th Amendment of the Constitution). Women under 30 gained the vote in local elections in 1935[112] and in Dáil elections and referendums in 1922 (Constitution of the Irish Free State[113]). The only popular election (in 1925) to the Free State Seanad had a voting age of 30.[114] (See also History of the franchise in Ireland.)
Australia: 1973 (New South Wales was the first state to do so, in 1970)
France: 5 July 1974 (Act No. 74-631)[115]
New Zealand: November 1974 (from 20; previous reduction from 21 to 20 in 1969)[116][117]
Dominica: 1974[118]
Italy: 1975 (voting age to elect the Senate remained at 25)
Trinidad and Tobago: 1976
Denmark: 19 September 1978 (from 20; 53.8% in referendum; previous reductions were 25 to 23 in 1953, 23 to 21 in 1961 and 21 to 20 in 1971)[119]
Spain: 29 December 1978 (1978 Constitution)[120]
Peru: 1979 Constitution
Belgium: 1981[121]
India: 28 March 1989 (61st Constitution Amendment Act, 1988 read with Act 21 of 1989)[122]
Switzerland: 1991 (from 20; referendum held on 3 March)[123]
Austria: 1992 (from 19; previous reductions were 21 to 20 in 1949 and 20 to 19 in 1970)[124]
Estonia: 29 July 1992 (from 22, according to the 1938 Constitution; was 18 during the Soviet Occupation since 1940 and 16 for the Congress of Estonia in 1990)[125][126]
Hong Kong: 1995 (from 21)[127]
Liechtenstein: 2000 (from 20; LGBl. 2000 No. 55)[128]
Jordan: July 2001 (from 19; Provisional Election Law No. 34/2001)[129]
Pakistan: 21 August 2002 (Legal Framework Order, 2002),[130][131] was 18 under 1973 Constitution, then increased to 21, then lowered back to 18.[132]
Morocco: 11 December 2002 (from 20)[133]
Uzbekistan: July 2012 (from 25)
Saudi Arabia: April 2015 (from 21)[134]
Japan: June 2016 (from 20)[135]

text: Chronology of lowering the voting age to 16[edit]

text: This is a further list, similar to the above but of the dates upon which countries lowered the voting age to 16; unless otherwise indicated, the reduction was from 18.

text:
Nicaragua: November 1984 (from 21)[136][137]
Brazil: 5 October 1988 (Constitution of the Federative Republic of Brazil, 1988)[138]
Estonia: 24 February 1990 (from 22 according to the 1938 Constitution, from 18 during the Soviet occupation); only for the Congress of Estonia, was raised to 18 according to the 1992 Constitution
Isle of Man: 11 July 2006; legislation brought into force in time for general election held on 23 November 2006[139]
Austria: 1 July 2007 (BGBl. No. 1/1930, as amended)[24]
Guernsey: 19 December 2007 (Reform (Guernsey) (Amendment) Law, 2007)[53][80]
Jersey: 1 April 2008 (Public Elections (Amendment No. 2) (Jersey) Law 2008)[47]
Ecuador: 28 September 2008 (New constitution accepted by referendum) for general election on 26 March 2009.
Argentina: 1 November 2012. Voting for teenagers between 16 and 18 years of age became optional.[140]
Malta: 20 November 2013. Motion passed in parliament to lower the voting age to 16 at local council elections starting from 2015.[141]
Scotland: 18 September 2014. 16 & 17 years old were given the vote for the Independence Referendum. This was subsequently extended permanently as of the 2016 parliament election.[142]
Estonia: 6 May 2015 in local elections only.

text: Organizations in favour of lowering the voting age[edit]

text: This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (November 2008) (Learn how and when to remove this template message)

text: The following are political parties and other campaigning organisations that have either endorsed a lower voting age or who favour its removal.

text: Alphabetical list of countries[edit]

text: Australia[edit]

text:
Australian Democrats
Australian Greens
Australian Labor Party[75]

text: Austria[edit]

text:
The Greens – The Green Alternative
Liberal Forum[143]
Social Democratic Party of Austria[144]
vote4future.at Austrian National Youth Council[145]

text: Belgium[edit]

text:
Ecolo[146]
Groen[146]
Open Vlaamse Liberalen en Democraten[146]

text: Canada[edit]

text:
Communist Party of Canada
Green Party of Canada[147]
New Democratic Party
Parti Québécois[148]
voteto16.ca[149]

text: Denmark[edit]

text:
Social Democrats
Socialist People's Party
Dansk Ungdoms Fællesråd[150]

text: Estonia[edit]

text:
Estonian National Youth Council
Young Social Democrats

text: France[edit]

text: La France Insoumise[151]

text: Germany[edit]

text:
Foundation for the Rights of Future Generations[152]
K.R.Ä.T.Z.Ä. (demanding abolition of any age-based voting restrictions)[153]

text: Greece[edit]

text: Ecologist Greens[154]

text: Ireland[edit]

text:
Green Party[155]
Labour Party[156]
Sinn Féin[157]
Socialist Party[158]

text: In 2013, the Constitutional Convention was asked to consider reducing the voting age to 17 and recommended lowering it to 16.[159] The then government agreed to hold a referendum,[160] but in 2015 postponed it indefinitely to give priority to other referendums.[161]

text: Italy[edit]

text: Five Star Movement[162]

text: Malaysia[edit]

text: No political party had decreed that its members should all follow the party line about lowering voting age policy, resulting in public differences of view. Most parties had splits in their members and supporters, taking different sides.[163]

text:
Malaysian civil societies' demands (to 18)[164]
Coalition for Clean and Fair Elections (BERSIH) (to 18)[165]
Democratic Action Party (to 18)[166]
National Trust Party (to 18)[167]
Pan-Malaysian Islamic Party (to 18)
Parti Gerakan Rakyat Malaysia (to 18)[168]
Parti Sosialis Malaysia (to 18)[169]
People's Justice Party (to 18)

text: Netherlands[edit]

text: GroenLinks

text: New Zealand[edit]

text:
Green Party of Aotearoa New Zealand
New Zealand Labour Party

text: Norway[edit]

text:
Liberal Party[170]
Socialist Left Party[171]

text: Portugal[edit]

text:
Left Bloc
LIVRE/Tempo de Avançar
Socialist Party

text: Romania[edit]

text:
National Liberal Party[172]
National Union for the Progress of Romania[173]

text: Spain[edit]

text: Izquierda Unida

text: Sweden[edit]

text: Green Party[174]

text: United Kingdom[edit]

text:
Green Party of England and Wales[175]
Green Party in Northern Ireland[176]
Liberal Democrats[177]
Liberal Party[178]
National Health Action Party[179]
Plaid Cymru[180]
Scottish Conservative Party
Scottish Green Party
Scottish National Party
Scottish Socialist Party[181]
Social Democratic Labour Party
Ulster Unionist Party
Votes at 16

text: United States[edit]

text:
Americans for a Society Free from Age Restrictions (supports full elimination of voting age)
Future Voters of America[182]
Green Party of Texas[183]
National Youth Rights Association
Rock the Vote
Socialist Party USA (to 15)
FairVote
Vermont Libertarian Party