title: Ozone

text: According to experimental evidence from microwave spectroscopy, ozone is a bent molecule, with C symmetry (similar to the water molecule). The O – O distances are . The O – O – O angle is 116.78°. The central atom is "sp"² hybridized with one lone pair. Ozone is a polar molecule with a dipole moment of 0.53 D. The molecule can be represented as a resonance hybrid with two contributing structures, each with a single bond on one side and double bond on the other. The arrangement possesses an overall bond order of 1.5 for both sides. It is isoelectronic with the nitrite anion. Naturally occurring ozone can be composed of substituted isotopes (O, O, O). A cyclic form has been predicted but not observed.


title: Ozone

text: Ozone is among the most powerful oxidizing agents known, far stronger than O. It is also unstable at high concentrations, decaying into ordinary diatomic oxygen. Its half-life varies with atmospheric conditions such as temperature, humidity, and air movement. Under laboratory conditions, Half-Life Time (HLT) will average ~1500 minutes (25 hours) in "still" air at room temperature (24 °C), "zero" humidity with "zero" air changes per hour (ACH).


title: Ozone

text: This reaction proceeds more rapidly with increasing temperature. Deflagration of ozone can be triggered by a spark and can occur in ozone concentrations of 10 wt% or higher.


title: Ozone

text: Ozone can also be produced from oxygen at the anode of an electrochemical cell. This reaction can create smaller quantities of ozone for research purposes.


title: Ozone

text: This can be observed as an unwanted reaction in a Hoffman gas apparatus during the electrolysis of water when the voltage is set above the necessary voltage.


title: Ozone

text: Ozone will oxidize most metals (except gold, platinum, and iridium) to oxides of the metals in their highest oxidation state. For example:


title: Ozone

text: In an aqueous solution, however, two competing simultaneous reactions occur, one to produce elemental sulfur, and one to produce sulfuric acid:


title: Ozone

text: Alkenes can be oxidatively cleaved by ozone, in a process called ozonolysis, giving alcohols, aldehydes, ketones, and carboxylic acids, depending on the second step of the workup.


title: Ozone

text: Ozone can also cleave alkynes to form an acid anhydride or diketone product. If the reaction is performed in the presence of water, the anhydride hydrolyzes to give two carboxylic acids.


title: Ozone

text: Usually ozonolysis is carried out in a solution of dichloromethane, at a temperature of −78 °C. After a sequence of cleavage and rearrangement, an organic ozonide is formed. With reductive workup (e.g. zinc in acetic acid or dimethyl sulfide), ketones and aldehydes will be formed, with oxidative workup (e.g. aqueous or alcoholic hydrogen peroxide), carboxylic acids will be formed.


title: Ozone

text: All three atoms of ozone may also react, as in the reaction of tin(II) chloride with hydrochloric acid and ozone:


title: Ozone

text: Iodine perchlorate can be made by treating iodine dissolved in cold anhydrous perchloric acid with ozone:


title: Ozone

text: Ozone could also react with potassium iodide to give oxygen and iodine gas that can be titrated for quantitative determination :


title: Ozone

text: Ozone can be used for combustion reactions and combustible gases; ozone provides higher temperatures than burning in dioxygen (O). The following is a reaction for the combustion of carbon subnitride which can also cause higher temperatures:


title: Ozone

text: Ozone can react at cryogenic temperatures. At , atomic hydrogen reacts with liquid ozone to form a hydrogen superoxide radical, which dimerizes:


title: Ozone

text: Ozone is a toxic substance, commonly found or generated in human environments (aircraft cabins, offices with photocopiers, laser printers, sterilizers...) and its catalytic decomposition is very important to reduce pollution. This type of decomposition is the most widely used, especially with solid catalysts, and it has many advantages such as a higher conversion with a lower temperature. Furthermore, the product and the catalyst can be instantaneously separated, and this way the catalyst can be easily recovered without using any separation operation. Moreover, the most used materials in the catalytic decomposition of ozone in the gas phase are noble metals like Pt, Rh or Pd and transition metals such as Mn, Co, Cu, Fe, Ni or Ag.


title: Ozone

text: The first one is a thermal decomposition where the ozone can be decomposed using only the action of heat. The problem is that this type of decomposition is very slow with temperatures below 250 °C. However, the decomposition rate can be increased working with higher temperatures but this would involve a high energy cost.


title: Ozone

text: The second one is a photochemical decomposition, which consists of radiating ozone with ultraviolet radiation (UV) and it gives rise to oxygen and radical peroxide.


title: Ozone

text: The process of ozone decomposition is a complex reaction involving two elementary reactions that finally lead to molecular oxygen, and this means that the reaction order and the rate law cannot be determined by the stoichiometry of the fitted equation.


title: Ozone

text: It has been determined that the ozone decomposition follows a first order kinetics, and from the rate law above it can be determined that the partial order respect to molecular oxygen is -1 and respect to ozone is 2, therefore the global reaction order is 1.


title: Ozone

text: The ozone decomposition consists of two elementary steps: The first one corresponds to a unimolecular reaction because one only molecule of ozone decomposes into two products (molecular oxygen and oxygen). Then, the oxygen from the first step is an intermediate because it participates as a reactant in the second step, which is a bimolecular reaction because there are two different reactants (ozone and oxygen) that give rise to one product, that corresponds to molecular oxygen in the gas phase.


title: Ozone

text: These two steps have different reaction rates, the first one is reversible and faster than the second reaction, which is slower, so this means that the determining step is the second reaction and this is used to determine the observed reaction rate. The reaction rate laws for every step are the ones that follow:


title: Ozone

text: The following mechanism allows to explain the rate law of the ozone decomposition observed experimentally, and also it allows to determine the reaction orders with respect to ozone and oxygen, with which the overall reaction order will be determined. The slower step, the bimolecular reaction, is the one that determines the rate of product formation, and considering that this step gives rise to two oxygen molecules the rate law has this form:


title: Ozone

text: However, this equation depends on the concentration of oxygen (intermediate), which can be determined considering the first step. Since the first step is faster and reversible and the second step is slower, the reactants and products from the first step are in equilibrium, so the concentration of the intermediate can be determined as follows:


title: Ozone

text: Finally, the mechanism presented allows to establish the rate observed experimentally, with a rate constant (K) and corresponding to a first order kinetics, as follows:


title: Ozone

text: Reduction of ozone gives the ozonide anion, O. Derivatives of this anion are explosive and must be stored at cryogenic temperatures. Ozonides for all the alkali metals are known. KO, RbO, and CsO can be prepared from their respective superoxides:


title: Ozone

text: NaO and LiO must be prepared by action of CsO in liquid NH on an ion-exchange resin containing Na or Li ions:


title: Ozone

text: Ozone can be used to remove iron and manganese from water, forming a precipitate which can be filtered:


title: Ozone

text: Ozone is a bent triatomic molecule with three vibrational modes: the symmetric stretch (1103.157 cm), bend (701.42 cm) and antisymmetric stretch (1042.096 cm). The symmetric stretch and bend are weak absorbers, but the antisymmetric stretch is strong and responsible for ozone being an important minor greenhouse gas. This IR band is also used to detect ambient and atmospheric ozone although UV-based measurements are more common.


title: Ozone

text: The electromagnetic spectrum of ozone is quite complex. An overview can be seen at the MPI Mainz UV/VIS Spectral Atlas of Gaseous Molecules of Atmospheric Interest.


title: Ozone

text: All of the bands are dissociative, meaning that the molecule falls apart to after absorbing a photon. The most important absorption is the Hartley band, extending from slightly above 300 nm down to slightly above 200 nm. It is this band that is responsible for absorbing UV C in the stratosphere.


title: Ozone

text: On the high wavelength side, the Hartley band transitions to the so-called Huggins band, which falls off rapidly until disappearing by ~360 nm. Above 400 nm, extending well out into the NIR, are the Chappius and Wulf bands. There, unstructured absorption bands are useful for detecting high ambient concentrations of ozone, but are so weak that they do not have much practical effect.


title: Ozone

text: There are additional absorption bands in the far UV, which increase slowly from 200 nm down to reaching a maximum at ~120 nm.


title: Ozone

text: The standard way to express total ozone levels (the amount of ozone in a given vertical column) in the atmosphere is by using Dobson units. Point measurements are reported as mole fractions in nmol/mol (parts per billion, ppb) or as concentrations in μg/m. The study of ozone concentration in the atmosphere started in the 1920s.


title: Ozone

text: The highest levels of ozone in the atmosphere are in the stratosphere, in a region also known as the ozone layer between about 10 and 50 km above the surface (or between about 6 and 31 miles). However, even in this "layer", the ozone concentrations are only two to eight parts per million, so most of the oxygen there is dioxygen, O, at about 210,000 parts per million by volume.


title: Ozone

text: Ozone in the stratosphere is mostly produced from short-wave ultraviolet rays between 240 and 160 nm. Oxygen starts to absorb weakly at 240 nm in the Herzberg bands, but most of the oxygen is dissociated by absorption in the strong Schumann–Runge bands between 200 and 160 nm where ozone does not absorb. While shorter wavelength light, extending to even the X-Ray limit, is energetic enough to dissociate molecular oxygen, there is relatively little of it, and, the strong solar emission at Lyman-alpha, 121 nm, falls at a point where molecular oxygen absorption is a minimum.


title: Ozone

text: The process of ozone creation and destruction is called the Chapman cycle and starts with the photolysis of molecular oxygen


title: Ozone

text: where "M" denotes the third body that carries off the excess energy of the reaction. The ozone molecule can then absorb a UV-C photon and dissociate


title: Ozone

text: The excess kinetic energy heats the stratosphere when the O atoms and the molecular oxygen fly apart and collide with other molecules. This conversion of UV light into kinetic energy warms the stratosphere. The oxygen atoms produced in the photolysis of ozone then react back with other oxygen molecule as in the previous step to form more ozone. In the clear atmosphere, with only nitrogen and oxygen, ozone can react with the atomic oxygen to form two molecules of O


title: Ozone

text: An estimate of the rate of this termination step to the cycling of atomic oxygen back to ozone can be found simply by taking the ratios of the concentration of O to O. The termination reaction is catalysed by the presence of certain free radicals, of which the most important are hydroxyl (OH), nitric oxide (NO) and atomic chlorine (Cl) and bromine (Br). In the second half of the 20th century, the amount of ozone in the stratosphere was discovered to be declining, mostly because of increasing concentrations of chlorofluorocarbons (CFC) and similar chlorinated and brominated organic molecules. The concern over the health effects of the decline led to the 1987 Montreal Protocol, the ban on the production of many ozone depleting chemicals and in the first and second decade of the 21st century the beginning of the recovery of stratospheric ozone concentrations.


title: Ozone

text: Ozone in the ozone layer filters out sunlight wavelengths from about 200 nm UV rays to 315 nm, with ozone peak absorption at about 250 nm. This ozone UV absorption is important to life, since it extends the absorption of UV by ordinary oxygen and nitrogen in air (which absorb all wavelengths < 200 nm) through the lower UV-C (200–280 nm) and the entire UV-B band (280–315 nm). The small unabsorbed part that remains of UV-B after passage through ozone causes sunburn in humans, and direct DNA damage in living tissues in both plants and animals. Ozone's effect on mid-range UV-B rays is illustrated by its effect on UV-B at 290 nm, which has a radiation intensity 350 million times as powerful at the top of the atmosphere as at the surface. Nevertheless, enough of UV-B radiation at similar frequency reaches the ground to cause some sunburn, and these same wavelengths are also among those responsible for the production of vitamin D in humans.


title: Ozone

text: The ozone layer has little effect on the longer UV wavelengths called UV-A (315–400 nm), but this radiation does not cause sunburn or direct DNA damage, and while it probably does cause long-term skin damage in certain humans, it is not as dangerous to plants and to the health of surface-dwelling organisms on Earth in general (see ultraviolet for more information on near ultraviolet).


title: Ozone

text: Low level ozone (or tropospheric ozone) is an atmospheric pollutant. It is not emitted directly by car engines or by industrial operations, but formed by the reaction of sunlight on air containing hydrocarbons and nitrogen oxides that react to form ozone directly at the source of the pollution or many kilometers downwind.


title: Ozone

text: Ozone reacts directly with some hydrocarbons such as aldehydes and thus begins their removal from the air, but the products are themselves key components of smog. Ozone photolysis by UV light leads to production of the hydroxyl radical HO• and this plays a part in the removal of hydrocarbons from the air, but is also the first step in the creation of components of smog such as peroxyacyl nitrates, which can be powerful eye irritants. The atmospheric lifetime of tropospheric ozone is about 22 days; its main removal mechanisms are being deposited to the ground, the above-mentioned reaction giving HO•, and by reactions with OH and the peroxy radical HO•.


title: Ozone

text: There is evidence of significant reduction in agricultural yields because of increased ground-level ozone and pollution which interferes with photosynthesis and stunts overall growth of some plant species. The United States Environmental Protection Agency is proposing a secondary regulation to reduce crop damage, in addition to the primary regulation designed for the protection of human health.


title: Ozone

text: Certain examples of cities with elevated ozone readings are Denver, Colorado; Houston, Texas; and Mexico City, Mexico. Houston has a reading of around 41 nmol/mol, while Mexico City is far more hazardous, with a reading of about 125 nmol/mol.


title: Ozone

text: Low level ozone, or tropospheric ozone, is the most concerning type of ozone pollution in urban areas and is increasing in general. Ozone pollution in urban areas affects denser populations, and is worsened by high populations of vehicles, which emit pollutants NO and VOCs, the main contributors to problematic ozone levels. Ozone pollution in urban areas is especially concerning with increasing temperatures, raising heat-related mortality during heat waves. During heat waves in urban areas, ground level ozone pollution can be 20% higher than usual. Ozone pollution in urban areas reaches higher levels of exceedance in the summer and autumn, which may be explained by weather patterns and traffic patterns. People experiencing poverty are more affected by pollution in general, even though these populations are less likely to be contributing to pollution levels.


title: Ozone

text: As mentioned above, Denver, Colorado, is one of the many cities in the United States that have high amounts of ozone. According to the American Lung Association, the Denver-Aurora area is the 14th most ozone-polluted area in the United States. The problem of high ozone levels is not new to this area. In 2004, "the US Environmental Protection Agency designated the Denver Metro/North Front Range (Adams, Arapahoe, Boulder, Broomfield, Denver, Douglas, Jefferson, and parts of Larimer and Weld counties) as nonattainment for the 1997 8-hour ozone standard", but later deferred this nonattainment status until 2007. The nonattainment standard indicates that an area does not meet the EPA's air quality standards. The Colorado Ozone Action Plan was created in response, and numerous changes were implemented from this plan. The first major change was that car emission testing was expanded across the state to more counties that did not previously mandate emissions testing, like areas of Larimer and Weld County. There have also been changes made to decrease Nitrogen Oxides (NOx) and Volatile Organic Compound (VOC) emissions, which should help lower ozone levels.


title: Ozone

text: One large contributor to high ozone levels in the area is the oil and natural gas industry situated in the Denver-Julesburg Basin (DJB) which overlaps with a majority of Colorado's metropolitan areas. Ozone is created naturally in the Earth's stratosphere, but is also created in the troposphere from human efforts. Briefly mentioned above, NOx and VOCs react with sunlight to create ozone through a process called photochemistry. One hour elevated ozone events (<75 ppb) "occur during June–August indicating that elevated ozone levels are driven by regional photochemistry". According to an article from the University of Colorado-Boulder, "Oil and natural gas VOC emission have a major role in ozone production and bear the potential to contribute to elevated O levels in the Northern Colorado Front Range (NCFR)".  Using complex analyses to research wind patterns and emissions from large oil and natural gas operations, the authors concluded that "elevated O levels in the NCFR are predominantly correlated with air transport from N– ESE, which are the upwind sectors where the O&NG operations in the Wattenberg Field area of the DJB are located".


title: Ozone

text: Contained in the Colorado Ozone Action Plan, created in 2008, plans exist to evaluate "emission controls for large industrial sources of NOx" and "statewide control requirements for new oil and gas condensate tanks and pneumatic valves". In 2011, the Regional Haze Plan was released that included a more specific plan to help decrease NOx emissions. These efforts are increasingly difficult to implement and take many years to come to pass. Of course there are also other reasons that ozone levels remain high. These include: a growing population meaning more car emissions, and the mountains along the NCFR that can trap emissions. If interested, daily air quality readings can be found at the Colorado Department of Public Health and Environment's website. As noted earlier, Denver continues to experience high levels of ozone to this day. It will take many years and a systems-thinking approach to combat this issue of high ozone levels in the Front Range of Colorado.


title: Ozone

text: Ozone gas attacks any polymer possessing olefinic or double bonds within its chain structure, such as natural rubber, nitrile rubber, and styrene-butadiene rubber. Products made using these polymers are especially susceptible to attack, which causes cracks to grow longer and deeper with time, the rate of crack growth depending on the load carried by the rubber component and the concentration of ozone in the atmosphere. Such materials can be protected by adding antiozonants, such as waxes, which bond to the surface to create a protective film or blend with the material and provide long term protection. Ozone cracking used to be a serious problem in car tires, for example, but it is not an issue with modern tires. On the other hand, many critical products, like gaskets and O-rings, may be attacked by ozone produced within compressed air systems. Fuel lines made of reinforced rubber are also susceptible to attack, especially within the engine compartment, where some ozone is produced by electrical components. Storing rubber products in close proximity to a DC electric motor can accelerate ozone cracking. The commutator of the motor generates sparks which in turn produce ozone.


title: Ozone

text: Although ozone was present at ground level before the Industrial Revolution, peak concentrations are now far higher than the pre-industrial levels, and even background concentrations well away from sources of pollution are substantially higher. Ozone acts as a greenhouse gas, absorbing some of the infrared energy emitted by the earth. Quantifying the greenhouse gas potency of ozone is difficult because it is not present in uniform concentrations across the globe. However, the most widely accepted scientific assessments relating to climate change (e.g. the Intergovernmental Panel on Climate Change Third Assessment Report) suggest that the radiative forcing of tropospheric ozone is about 25% that of carbon dioxide.


title: Ozone

text: The annual global warming potential of tropospheric ozone is between 918 and 1022 tons carbon dioxide equivalent/tons tropospheric ozone. This means on a per-molecule basis, ozone in the troposphere has a radiative forcing effect roughly 1,000 times as strong as carbon dioxide. However, tropospheric ozone is a short-lived greenhouse gas, which decays in the atmosphere much more quickly than carbon dioxide. This means that over a 20-year span, the global warming potential of tropospheric ozone is much less, roughly 62 to 69 tons carbon dioxide equivalent / ton tropospheric ozone.


title: Ozone

text: Because of its short-lived nature, tropospheric ozone does not have strong global effects, but has very strong radiative forcing effects on regional scales. In fact, there are regions of the world where tropospheric ozone has a radiative forcing up to 150% of carbon dioxide. For example, ozone increase in the troposphere is shown to be responsible for ~30% of upper Southern Ocean interior warming between 1955 and 2000.


title: Ozone

text: For the last few decades, scientists studied the effects of acute and chronic ozone exposure on human health. Hundreds of studies suggest that ozone is harmful to people at levels currently found in urban areas. Ozone has been shown to affect the respiratory, cardiovascular and central nervous system. Early death and problems in reproductive health and development are also shown to be associated with ozone exposure.


title: Ozone

text: The American Lung Association has identified five populations who are especially vulnerable to the effects of breathing ozone:


title: Ozone

text: Additional evidence suggests that women, those with obesity and low-income populations may also face higher risk from ozone, although more research is needed.


title: Ozone

text: Acute ozone exposure ranges from hours to a few days. Because ozone is a gas, it directly affects the lungs and the entire respiratory system. Inhaled ozone causes inflammation and acute—but reversible—changes in lung function, as well as airway hyperresponsiveness. These changes lead to shortness of breath, wheezing, and coughing which may exacerbate lung diseases, like asthma or chronic obstructive pulmonary disease (COPD) resulting in the need to receive medical treatment. Acute and chronic exposure to ozone has been shown to cause an increased risk of respiratory infections, due to the following mechanism.


title: Ozone

text: Multiple studies have been conducted to determine the mechanism behind ozone's harmful effects, particularly in the lungs. These studies have shown that exposure to ozone causes changes in the immune response within the lung tissue, resulting in disruption of both the innate and adaptive immune response, as well as altering the protective function of lung epithelial cells. It is thought that these changes in immune response and the related inflammatory response are factors that likely contribute to the increased risk of lung infections, and worsening or triggering of asthma and reactive airways after exposure to ground-level ozone pollution.


title: Ozone

text: The innate (cellular) immune system consists of various chemical signals and cell types that work broadly and against multiple pathogen types, typically bacteria or foreign bodies/substances in the host. The cells of the innate system include phagocytes, neutrophils, both thought to contribute to the mechanism of ozone pathology in the lungs, as the functioning of these cell types have been shown to change after exposure to ozone. Macrophages, cells that serve the purpose of eliminating pathogens or foreign material through the process of "phagocytosis", have been shown to change the level of inflammatory signals they release in response to ozone, either up-regulating and resulting in an inflammatory response in the lung, or down-regulating and reducing immune protection. Neutrophils, another important cell type of the innate immune system that primarily targets bacterial pathogens, are found to be present in the airways within 6 hours of exposure to high ozone levels. Despite high levels in the lung tissues, however, their ability to clear bacteria appears impaired by exposure to ozone.


title: Ozone

text: The adaptive immune system is the branch of immunity that provides long-term protection via the development of antibodies targeting specific pathogens and is also impacted by high ozone exposure. Lymphocytes, a cellular component of the adaptive immune response, produce an increased amount of inflammatory chemicals called "cytokines" after exposure to ozone, which may contribute to airway hyperreactivity and worsening asthma symptoms.


title: Ozone

text: The airway epithelial cells also play an important role in protecting individuals from pathogens. In normal tissue, the epithelial layer forms a protective barrier, and also contains specialized ciliary structures that work to clear foreign bodies, mucus and pathogens from the lungs. When exposed to ozone, the cilia become damaged and mucociliary clearance of pathogens is reduced. Furthermore, the epithelial barrier becomes weakened, allowing pathogens to cross the barrier, proliferate and spread into deeper tissues. Together, these changes in the epithelial barrier help make individuals more susceptible to pulmonary infections.


title: Ozone

text: Inhaling ozone not only affects the immune system and lungs, but it may also affect the heart as well. Ozone causes short-term autonomic imbalance leading to changes in heart rate and reduction in heart rate variability; and high levels exposure for as little as one-hour results in a supraventricular arrhythmia in the elderly, both increase the risk of premature death and stroke. Ozone may also lead to vasoconstriction resulting in increased systemic arterial pressure contributing to increased risk of cardiac morbidity and mortality in patients with pre-existing cardiac diseases.


title: Ozone

text: Breathing ozone for periods longer than eight hours at a time for weeks, months or years defines chronic exposure. Numerous studies suggest a serious impact on the health of various populations from this exposure.


title: Ozone

text: One study finds significant positive associations between chronic ozone and all-cause, circulatory, and respiratory mortality with 2%, 3%, and 12% increases in risk per 10 ppb and report an association (95% CI) of annual ozone and all-cause mortality with a hazard ratio of 1.02 (1.01–1.04), and with cardiovascular mortality of 1.03 (1.01–1.05). A similar study finds similar associations with all-cause mortality and even larger effects for cardiovascular mortality. An increased risk of mortality from respiratory causes is associated with long-term chronic exposure to ozone.


title: Ozone

text: Chronic ozone has detrimental effects on children, especially those with asthma. The risk for hospitalization in children with asthma increases with chronic exposure to ozone; younger children and those with low-income status are even at greater risk.


title: Ozone

text: Adults suffering from respiratory diseases (asthma, COPD, lung cancer) are at a higher risk of mortality and morbidity and critically ill patients have an increased risk of developing acute respiratory distress syndrome with chronic ozone exposure as well.


title: Ozone

text: Ozone generators sold as air cleaners intentionally produce the gas ozone. These are often marketed to control indoor air pollution, and use misleading terms to describe ozone. Some examples are describing it as "energized oxygen" or "pure air", suggesting that ozone is a healthy or "better" kind of oxygen. However, according to the EPA, "ozone is not effective at removing many odor-causing chemicals"" and "does not effectively remove viruses, bacteria, mold, or other biological pollutants"." Furthermore, another report states that "results of some controlled studies show that concentrations of ozone considerably higher than these [human safety] standards are possible even when a user follows the manufacturer's operating instructions".


title: Ozone

text: The California Air Resources Board has a page listing air cleaners (many with ionizers) meeting their indoor ozone limit of 0.050 parts per million. From that article:


title: Ozone

text: Ozone precursors are a group of pollutants, predominantly those emitted during the combustion of fossil fuels. Ground-level ozone pollution (tropospheric ozone) is created near the Earth's surface by the action of daylight UV rays on these precursors. The ozone at ground level is primarily from fossil fuel precursors, but methane is a natural precursor, and the very low natural background level of ozone at ground level is considered safe. This section examines the health impacts of fossil fuel burning, which raises ground level ozone far above background levels.


title: Ozone

text: There is a great deal of evidence to show that ground-level ozone can harm lung function and irritate the respiratory system. Exposure to ozone (and the pollutants that produce it) is linked to premature death, asthma, bronchitis, heart attack, and other cardiopulmonary problems.


title: Ozone

text: Long-term exposure to ozone has been shown to increase risk of death from respiratory illness. A study of 450,000 people living in United States cities saw a significant correlation between ozone levels and respiratory illness over the 18-year follow-up period. The study revealed that people living in cities with high ozone levels, such as Houston or Los Angeles, had an over 30% increased risk of dying from lung disease.


title: Ozone

text: Air quality guidelines such as those from the World Health Organization, the United States Environmental Protection Agency (EPA) and the European Union are based on detailed studies designed to identify the levels that can cause measurable ill health effects.


title: Ozone

text: According to scientists with the US EPA, susceptible people can be adversely affected by ozone levels as low as 40 nmol/mol. In the EU, the current target value for ozone concentrations is 120 µg/m which is about 60 nmol/mol. This target applies to all member states in accordance with Directive 2008/50/EC. Ozone concentration is measured as a maximum daily mean of 8 hour averages and the target should not be exceeded on more than 25 calendar days per year, starting from January 2010. Whilst the directive requires in the future a strict compliance with 120 µg/m limit (i.e. mean ozone concentration not to be exceeded on any day of the year), there is no date set for this requirement and this is treated as a long-term objective.


title: Ozone

text: In the US, the Clean Air Act directs the EPA to set National Ambient Air Quality Standards for several pollutants, including ground-level ozone, and counties out of compliance with these standards are required to take steps to reduce their levels. In May 2008, under a court order, the EPA lowered its ozone standard from 80 nmol/mol to 75 nmol/mol. The move proved controversial, since the Agency's own scientists and advisory board had recommended lowering the standard to 60 nmol/mol. Many public health and environmental groups also supported the 60 nmol/mol standard, and the World Health Organization recommends 100 µg/m (51 nmol/mol).


title: Ozone

text: On January 7, 2010, the U.S. Environmental Protection Agency (EPA) announced proposed revisions to the National Ambient Air Quality Standard (NAAQS) for the pollutant ozone, the principal component of smog:


title: Ozone

text: ... EPA proposes that the level of the 8-hour primary standard, which was set at 0.075 μmol/mol in the 2008 final rule, should instead be set at a lower level within the range of 0.060 to 0.070 μmol/mol, to provide increased protection for children and other "at risk" populations against an array of – related adverse health effects that range from decreased lung function and increased respiratory symptoms to serious indicators of respiratory morbidity including emergency department visits and hospital admissions for respiratory causes, and possibly cardiovascular-related morbidity as well as total non- accidental and cardiopulmonary mortality ...


title: Ozone

text: On October 26, 2015, the EPA published a final rule with an effective date of December 28, 2015 that revised the 8-hour primary NAAQS from 0.075 ppm to 0.070 ppm.


title: Ozone

text: The EPA has developed an air quality index (AQI) to help explain air pollution levels to the general public. Under the current standards, eight-hour average ozone mole fractions of 85 to 104 nmol/mol are described as "unhealthy for sensitive groups", 105 nmol/mol to 124 nmol/mol as "unhealthy", and 125 nmol/mol to 404 nmol/mol as "very unhealthy".


title: Ozone

text: Ozone can also be present in indoor air pollution, partly as a result of electronic equipment such as photocopiers. A connection has also been known to exist between the increased pollen, fungal spores, and ozone caused by thunderstorms and hospital admissions of asthma sufferers.


title: Ozone

text: In the Victorian era, one British folk myth held that the smell of the sea was caused by ozone. In fact, the characteristic "smell of the sea" is caused by dimethyl sulfide, a chemical generated by phytoplankton. Victorian Britons considered the resulting smell "bracing".


title: Ozone

text: An investigation to assess the joint mortality effects of ozone and heat during the European heat waves in 2003, concluded that these appear to be additive.


title: Ozone

text: Ozone, along with reactive forms of oxygen such as superoxide, singlet oxygen, hydrogen peroxide, and hypochlorite ions, is produced by white blood cells and other biological systems (such as the roots of marigolds) as a means of destroying foreign bodies. Ozone reacts directly with organic double bonds. Also, when ozone breaks down to dioxygen it gives rise to oxygen free radicals, which are highly reactive and capable of damaging many organic molecules. Moreover, it is believed that the powerful oxidizing properties of ozone may be a contributing factor of inflammation. The cause-and-effect relationship of how the ozone is created in the body and what it does is still under consideration and still subject to various interpretations, since other body chemical processes can trigger some of the same reactions. There is evidence linking the antibody-catalyzed water-oxidation pathway of the human immune response to the production of ozone. In this system, ozone is produced by antibody-catalyzed production of trioxidane from water and neutrophil-produced singlet oxygen.


title: Ozone

text: When inhaled, ozone reacts with compounds lining the lungs to form specific, cholesterol-derived metabolites that are thought to facilitate the build-up and pathogenesis of atherosclerotic plaques (a form of heart disease). These metabolites have been confirmed as naturally occurring in human atherosclerotic arteries and are categorized into a class of secosterols termed "atheronals", generated by ozonolysis of cholesterol's double bond to form a 5,6 secosterol as well as a secondary condensation product via aldolization.


title: Ozone

text: Ozone has been implicated to have an adverse effect on plant growth: "... ozone reduced total chlorophylls, carotenoid and carbohydrate concentration, and increased 1-aminocyclopropane-1-carboxylic acid (ACC) content and ethylene production. In treated plants, the ascorbate leaf pool was decreased, while lipid peroxidation and solute leakage were significantly higher than in ozone-free controls. The data indicated that ozone triggered protective mechanisms against oxidative stress in citrus." Studies that have used pepper plants as a model have shown that ozone decreased fruit yield and changed fruit quality. Furthermore, it was also observed a decrease in chlorophylls levels and antioxidant defences on the leaves, as well as increased the reactive oxygen species (ROS) levels and lipid and protein damages.


title: Ozone

text: A 2022 study concludes that East Asia loses 63 billion Dollars in crops per year due to ozone pollution, a by-product of fossile fuel combustion. China loses about one third of its potential wheat production and one fourth of its rice production.


title: Ozone

text: Because of the strongly oxidizing properties of ozone, ozone is a primary irritant, affecting especially the eyes and respiratory systems and can be hazardous at even low concentrations. The Canadian Centre for Occupation Safety and Health reports that:


title: Ozone

text: Even very low concentrations of ozone can be harmful to the upper respiratory tract and the lungs. The severity of injury depends on both the concentration of ozone and the duration of exposure. Severe and permanent lung injury or death could result from even a very short-term exposure to relatively low concentrations."


title: Ozone

text: To protect workers potentially exposed to ozone, U.S. Occupational Safety and Health Administration has established a permissible exposure limit (PEL) of 0.1 μmol/mol (29 CFR 1910.1000 table Z-1), calculated as an 8-hour time weighted average. Higher concentrations are especially hazardous and NIOSH has established an Immediately Dangerous to Life and Health Limit (IDLH) of 5 μmol/mol. Work environments where ozone is used or where it is likely to be produced should have adequate ventilation and it is prudent to have a monitor for ozone that will alarm if the concentration exceeds the OSHA PEL. Continuous monitors for ozone are available from several suppliers.


title: Ozone

text: Elevated ozone exposure can occur on passenger aircraft, with levels depending on altitude and atmospheric turbulence. United States Federal Aviation Administration regulations set a limit of 250 nmol/mol with a maximum four-hour average of 100 nmol/mol. Some planes are equipped with ozone converters in the ventilation system to reduce passenger exposure.


title: Ozone

text: Ozone generators, or ozonators, are used to produce ozone for cleaning air or removing smoke odours in unoccupied rooms. These ozone generators can produce over 3 g of ozone per hour. Ozone often forms in nature under conditions where O will not react. Ozone used in industry is measured in μmol/mol (ppm, parts per million), nmol/mol (ppb, parts per billion), μg/m, mg/h (milligrams per hour) or weight percent. The regime of applied concentrations ranges from 1% to 5% (in air) and from 6% to 14% (in oxygen) for older generation methods. New electrolytic methods can achieve up 20% to 30% dissolved ozone concentrations in output water.


title: Ozone

text: Temperature and humidity play a large role in how much ozone is being produced using traditional generation methods (such as corona discharge and ultraviolet light). Old generation methods will produce less than 50% of nominal capacity if operated with humid ambient air, as opposed to very dry air. New generators, using electrolytic methods, can achieve higher purity and dissolution through using water molecules as the source of ozone production.


title: Ozone

text: This is the most common type of ozone generator for most industrial and personal uses. While variations of the "hot spark" coronal discharge method of ozone production exist, including medical grade and industrial grade ozone generators, these units usually work by means of a corona discharge tube or ozone plate. They are typically cost-effective and do not require an oxygen source other than the ambient air to produce ozone concentrations of 3–6%. Fluctuations in ambient air, due to weather or other environmental conditions, cause variability in ozone production. However, they also produce nitrogen oxides as a by-product. Use of an air dryer can reduce or eliminate nitric acid formation by removing water vapor and increase ozone production. At room temperature, nitric acid will form into a vapour that is hazardous if inhaled. Symptoms can include chest pain, shortness of breath, headaches and a dry nose and throat causing a burning sensation. Use of an oxygen concentrator can further increase the ozone production and further reduce the risk of nitric acid formation by removing not only the water vapor, but also the bulk of the nitrogen.


title: Ozone

text: UV ozone generators, or vacuum-ultraviolet (VUV) ozone generators, employ a light source that generates a narrow-band ultraviolet light, a subset of that produced by the Sun. The Sun's UV sustains the ozone layer in the stratosphere of Earth.


title: Ozone

text: UV ozone generators use ambient air for ozone production, no air prep systems are used (air dryer or oxygen concentrator), therefore these generators tend to be less expensive. However, UV ozone generators usually produce ozone with a concentration of about 0.5% or lower which limits the potential ozone production rate. Another disadvantage of this method is that it requires the ambient air (oxygen) to be exposed to the UV source for a longer amount of time, and any gas that is not exposed to the UV source will not be treated. This makes UV generators impractical for use in situations that deal with rapidly moving air or water streams (in-duct air sterilization, for example). Production of ozone is one of the potential dangers of ultraviolet germicidal irradiation. VUV ozone generators are used in swimming pools and spa applications ranging to millions of gallons of water. VUV ozone generators, unlike corona discharge generators, do not produce harmful nitrogen by-products and also unlike corona discharge systems, VUV ozone generators work extremely well in humid air environments. There is also not normally a need for expensive off-gas mechanisms, and no need for air driers or oxygen concentrators which require extra costs and maintenance.


title: Ozone

text: In the cold plasma method, pure oxygen gas is exposed to a plasma created by DBD. The diatomic oxygen is split into single atoms, which then recombine in triplets to form ozone.


title: Ozone

text: It is common in the industry to mislabel some DBD ozone generators as CD Corona Discharge generators. Typically all solid flat metal electrode ozone generators produce ozone using the dielectric barrier discharge method.


title: Ozone

text: Cold plasma machines use pure oxygen as the input source and produce a maximum concentration of about 24% ozone. They produce far greater quantities of ozone in a given time compared to ultraviolet production that has about 2% efficiency.


title: Ozone

text: The discharges manifest as filamentary transfer of electrons (micro discharges) in a gap between two electrodes. In order to evenly distribute the micro discharges, a dielectric insulator must be used to separate the metallic electrodes and to prevent arcing.


title: Ozone

text: In most EOG methods, the hydrogen gas will be removed to leave oxygen and ozone as the only reaction products. Therefore, EOG can achieve higher dissolution in water without other competing gases found in corona discharge method, such as nitrogen gases present in ambient air. This method of generation can achieve concentrations of 20–30% and is independent of air quality because water is used as the source material. Production of ozone electrolytically is typically unfavorable because of the high overpotential required to produce ozone as compared to oxygen. This is why ozone is not produced during typical water electrolysis. However, it is possible to increase the overpotential of oxygen by careful catalyst selection such that ozone is preferentially produced under electrolysis. Catalysts typically chosen for this approach are lead dioxide or boron-doped diamond.


title: Ozone

text: The ozone to oxygen ratio is improved by increasing current density at the anode, cooling the electrolyte around the anode close to 0 °C, using an acidic electrolyte (such as dilute sulfuric acid) instead of a basic solution, and by applying pulsed current instead of DC.


title: Ozone

text: Ozone cannot be stored and transported like other industrial gases (because it quickly decays into diatomic oxygen) and must therefore be produced on site. Available ozone generators vary in the arrangement and design of the high-voltage electrodes. At production capacities higher than 20 kg per hour, a gas/water tube heat-exchanger may be utilized as ground electrode and assembled with tubular high-voltage electrodes on the gas-side. The regime of typical gas pressures is around absolute in oxygen and absolute in air. Several megawatts of electrical power may be installed in large facilities, applied as single phase AC current at 50 to 8000 Hz and peak voltages between 3,000 and 20,000 volts. Applied voltage is usually inversely related to the applied frequency.


title: Ozone

text: The dominating parameter influencing ozone generation efficiency is the gas temperature, which is controlled by cooling water temperature and/or gas velocity. The cooler the water, the better the ozone synthesis. The lower the gas velocity, the higher the concentration (but the lower the net ozone produced). At typical industrial conditions, almost 90% of the effective power is dissipated as heat and needs to be removed by a sufficient cooling water flow.


title: Ozone

text: Because of the high reactivity of ozone, only a few materials may be used like stainless steel (quality 316L), titanium, aluminium (as long as no moisture is present), glass, polytetrafluorethylene, or polyvinylidene fluoride. Viton may be used with the restriction of constant mechanical forces and absence of humidity (humidity limitations apply depending on the formulation). Hypalon may be used with the restriction that no water comes in contact with it, except for normal atmospheric levels. Embrittlement or shrinkage is the common mode of failure of elastomers with exposure to ozone. Ozone cracking is the common mode of failure of elastomer seals like O-rings.


title: Ozone

text: Silicone rubbers are usually adequate for use as gaskets in ozone concentrations below 1 wt%, such as in equipment for accelerated aging of rubber samples.


title: Ozone

text: Ozone may be formed from by electrical discharges and by action of high energy electromagnetic radiation. Unsuppressed arcing in electrical contacts, motor brushes, or mechanical switches breaks down the chemical bonds of the atmospheric oxygen surrounding the contacts [ → 2O]. Free radicals of oxygen in and around the arc recombine to create ozone []. Certain electrical equipment generate significant levels of ozone. This is especially true of devices using high voltages, such as ionic air purifiers, laser printers, photocopiers, tasers and arc welders. Electric motors using brushes can generate ozone from repeated sparking inside the unit. Large motors that use brushes, such as those used by elevators or hydraulic pumps, will generate more ozone than smaller motors.


title: Ozone

text: Ozone is similarly formed in the Catatumbo lightning storms phenomenon on the Catatumbo River in Venezuela, though ozone's instability makes it dubious that it has any effect on the ozonosphere.


title: Ozone

text: It is the world's largest single natural generator of ozone, lending calls for it to be designated a UNESCO World Heritage Site.


title: Ozone

text: In the laboratory, ozone can be produced by electrolysis using a 9 volt battery, a pencil graphite rod cathode, a platinum wire anode and a 3 molar sulfuric acid electrolyte. The half cell reactions taking place are:


title: Ozone

text: In the net reaction, three equivalents of water are converted into one equivalent of ozone and three equivalents of hydrogen. Oxygen formation is a competing reaction.


title: Ozone

text: It can also be generated by a high voltage arc. In its simplest form, high voltage AC, such as the output of a neon-sign transformer is connected to two metal rods with the ends placed sufficiently close to each other to allow an arc. The resulting arc will convert atmospheric oxygen to ozone.


title: Ozone

text: It is often desirable to contain the ozone. This can be done with an apparatus consisting of two concentric glass tubes sealed together at the top with gas ports at the top and bottom of the outer tube. The inner core should have a length of metal foil inserted into it connected to one side of the power source. The other side of the power source should be connected to another piece of foil wrapped around the outer tube. A source of dry is applied to the bottom port. When high voltage is applied to the foil leads, electricity will discharge between the dry dioxygen in the middle and form and which will flow out the top port. This is called a Siemen's ozoniser. The reaction can be summarized as follows:


title: Ozone

text: The largest use of ozone is in the preparation of pharmaceuticals, synthetic lubricants, and many other commercially useful organic compounds, where it is used to sever carbon-carbon bonds. It can also be used for bleaching substances and for killing microorganisms in air and water sources. Many municipal drinking water systems kill bacteria with ozone instead of the more common chlorine. Ozone has a very high oxidation potential. Ozone does not form organochlorine compounds, nor does it remain in the water after treatment. Ozone can form the suspected carcinogen bromate in source water with high bromide concentrations. The U.S. Safe Drinking Water Act mandates that these systems introduce an amount of chlorine to maintain a minimum of 0.2 μmol/mol residual free chlorine in the pipes, based on results of regular testing. Where electrical power is abundant, ozone is a cost-effective method of treating water, since it is produced on demand and does not require transportation and storage of hazardous chemicals. Once it has decayed, it leaves no taste or odour in drinking water.


title: Ozone

text: Although low levels of ozone have been advertised to be of some disinfectant use in residential homes, the concentration of ozone in dry air required to have a rapid, substantial effect on airborne pathogens exceeds safe levels recommended by the U.S. Occupational Safety and Health Administration and Environmental Protection Agency. Humidity control can vastly improve both the killing power of the ozone and the rate at which it decays back to oxygen (more humidity allows more effectiveness). Spore forms of most pathogens are very tolerant of atmospheric ozone in concentrations at which asthma patients start to have issues.


title: Ozone

text: In 1908 artificial ozonisation the Central Line of the London Underground was introduced as an aerial disinfectant. The process was found to be worthwhile, but was phased out by 1956. However the beneficial effect was maintained by the ozone created incidentally from the electrical discharges of the train motors (see above: Incidental production).


title: Ozone

text: Ozone generators were made available to schools and universities in Wales for the Autumn term 2021, to disinfect classrooms after COVID-19 outbreaks.


title: Ozone

text: Ozone is a reagent in many organic reactions in the laboratory and in industry. Ozonolysis is the cleavage of an alkene to carbonyl compounds.


title: Ozone

text: Many hospitals around the world use large ozone generators to decontaminate operating rooms between surgeries. The rooms are cleaned and then sealed airtight before being filled with ozone which effectively kills or neutralizes all remaining bacteria.


title: Ozone

text: Ozone is used as an alternative to chlorine or chlorine dioxide in the bleaching of wood pulp. It is often used in conjunction with oxygen and hydrogen peroxide to eliminate the need for chlorine-containing compounds in the manufacture of high-quality, white paper.


title: Ozone

text: Ozone can be used to detoxify cyanide wastes (for example from gold and silver mining) by oxidizing cyanide to cyanate and eventually to carbon dioxide.


title: Ozone

text: Since the invention of Dielectric Barrier Discharge (DBD) plasma reactors, it has been employed for water treatment with ozone. However, with cheaper alternative disinfectants like chlorine, such applications of DBD ozone water decontamination have been limited by high power consumption and bulky equipment. Despite this, with research revealing the negative impacts of common disinfectants like chlorine with respect to toxic residuals and ineffectiveness in killing certain micro-organisms, DBD plasma-based ozone decontamination is of interest in current available technologies. Although ozonation of water with a high concentration of bromide does lead to the formation of undesirable brominated disinfection byproducts, unless drinking water is produced by desalination, ozonation can generally be applied without concern for these byproducts. Advantages of ozone include high thermodynamic oxidation potential, less sensitivity to organic material and better tolerance for pH variations while retaining the ability to kill bacteria, fungi, viruses, as well as spores and cysts. Although, ozone has been widely accepted in Europe for decades, it is sparingly used for decontamination in the U.S due to limitations of high-power consumption, bulky installation and stigma attached with ozone toxicity. Considering this, recent research efforts have been directed towards the study of effective ozone water treatment systems Researchers have looked into lightweight and compact low power surface DBD reactors, energy efficient volume DBD reactors and low power micro-scale DBD reactors. Such studies can help pave the path to re-acceptance of DBD plasma-based ozone decontamination of water, especially in the U.S.


title: Ozone

text: Devices generating high levels of ozone, some of which use ionization, are used to sanitize and deodorize uninhabited buildings, rooms, ductwork, woodsheds, boats and other vehicles.


title: Ozone

text: Ozonated water is used to launder clothes and to sanitize food, drinking water, and surfaces in the home. According to the U.S. Food and Drug Administration (FDA), it is "amending the food additive regulations to provide for the safe use of ozone in gaseous and aqueous phases as an antimicrobial agent on food, including meat and poultry." Studies at California Polytechnic University demonstrated that 0.3 μmol/mol levels of ozone dissolved in filtered tapwater can produce a reduction of more than 99.99% in such food-borne microorganisms as salmonella, "E. coli" 0157:H7 and "Campylobacter". This quantity is 20,000 times the WHO-recommended limits stated above.


title: Ozone

text: Ozone is used in homes and hot tubs to kill bacteria in the water and to reduce the amount of chlorine or bromine required by reactivating them to their free state. Since ozone does not remain in the water long enough, ozone by itself is ineffective at preventing cross-contamination among bathers and must be used in conjunction with halogens. Gaseous ozone created by ultraviolet light or by corona discharge is injected into the water.


title: Ozone

text: Ozone is also widely used in the treatment of water in aquariums and fishponds. Its use can minimize bacterial growth, control parasites, eliminate transmission of some diseases, and reduce or eliminate "yellowing" of the water. Ozone must not come in contact with fishes' gill structures. Natural saltwater (with life forms) provides enough "instantaneous demand" that controlled amounts of ozone activate bromide ions to hypobromous acid, and the ozone entirely decays in a few seconds to minutes. If oxygen-fed ozone is used, the water will be higher in dissolved oxygen and fishes' gill structures will atrophy, making them dependent on oxygen-enriched water.


title: Ozone

text: Ozonation – a process of infusing water with ozone – can be used in aquaculture to facilitate organic breakdown. Ozone is also added to recirculating systems to reduce nitrite levels through conversion into nitrate. If nitrite levels in the water are high, nitrites will also accumulate in the blood and tissues of fish, where it interferes with oxygen transport (it causes oxidation of the heme-group of haemoglobin from ferrous () to ferric (), making haemoglobin unable to bind ). Despite these apparent positive effects, ozone use in recirculation systems has been linked to reducing the level of bioavailable iodine in salt water systems, resulting in iodine deficiency symptoms such as goitre and decreased growth in Senegalese sole ("Solea senegalensis") larvae.


title: Ozone

text: Ozonate seawater is used for surface disinfection of haddock and Atlantic halibut eggs against nodavirus. Nodavirus is a lethal and vertically transmitted virus which causes severe mortality in fish. Haddock eggs should not be treated with high ozone level as eggs so treated did not hatch and died after 3–4 days.


title: Ozone

text: Ozone application on freshly cut pineapple and banana shows increase in flavonoids and total phenol contents when exposure is up to 20 minutes. Decrease in ascorbic acid (one form of vitamin C) content is observed but the positive effect on total phenol content and flavonoids can overcome the negative effect. Tomatoes upon treatment with ozone shows an increase in β-carotene, lutein and lycopene. However, ozone application on strawberries in pre-harvest period shows decrease in ascorbic acid content.


title: Ozone

text: Ozone facilitates the extraction of some heavy metals from soil using EDTA. EDTA forms strong, water-soluble coordination compounds with some heavy metals (Pb, Zn) thereby making it possible to dissolve them out from contaminated soil. If contaminated soil is pre-treated with ozone, the extraction efficacy of Pb, Am and Pu increases by 11.0–28.9%, 43.5% and 50.7% respectively.


title: Ozone

text: Crop pollination is an essential part of an ecosystem. Ozone can have detrimental effects on plant-pollinator interactions. Pollinators carry pollen from one plant to another. This is an essential cycle inside of an ecosystem. Causing changes in certain atmospheric conditions around pollination sites or with xenobiotics could cause unknown changes to the natural cycles of pollinators and flowering plants. In a study conducted in North-Western Europe, crop pollinators were negatively affected more when ozone levels were higher.


title: Ozone

text: The use of ozone for the treatment of medical conditions is not supported by high quality evidence, and is generally considered alternative medicine.


title: Night Court

text: Night Court is an American television sitcom that aired on NBC from January 4, 1984 to May 31, 1992. The setting was the night shift of a Manhattan municipal court presided over by a young, unorthodox judge, Harold "Harry" T. Stone (portrayed by Harry Anderson). The series was created by comedy writer Reinhold Weege, who had previously worked on "Barney Miller" in the 1970s and early 1980s.


title: Night Court

text: The only actors to appear consistently throughout the show's run were Anderson, Larroquette, and Moll.


title: Night Court

text: Every episode of "Night Court" opens and closes with a jazz-influenced, bass-heavy theme tune composed by Jack Elliott, featuring Ernie Watts on saxophone while featuring video footage of prominent New York City landmarks such as the Brooklyn Bridge and the New York County Courthouse.


title: Night Court

text: "Night Court"s theme was used in the season-5 "Family Guy" episode "Bill & Peter's Bogus Journey", featuring animations of former US President Bill Clinton playing saxophone along with Secret Service musicians playing backup.


title: Night Court

text: "Night Court"s theme was sampled for the remix to Cam'Ron's 1998 single "Horse & Carriage". It was produced by Darrell "Digga" Branch and featured Big Pun, Charli Baltimore, Wyclef Jean, and Silkk the Shocker.


title: Night Court

text: Following the end credits theme music, a distinctive laugh can be heard dubbed over the vanity logo displaying producer Reinhold Weege's "Starry Night Productions". This same laugh can be heard coming from the studio audience throughout numerous seasons of "Night Court". At first it was thought to be the canned laugh of voice actor Mel Blanc or even star Harry Anderson; but in fact, it was the laugh of Chuck Weege, Reinhold's father, who attended nearly all of the tapings in person.


title: Night Court

text: "Night Court" received a number of awards and nominations. Both Selma Diamond (in 1985) and John Larroquette (in 1988) earned Golden Globe nominations, but lost to Faye Dunaway and Rutger Hauer, respectively. Paula Kelly was nominated for an Emmy after the first season. Larroquette won four consecutive Emmys for Outstanding Supporting Actor in a Comedy Series from 1985 to 1988, before he withdrew his name from the ballot in 1989. Selma Diamond was nominated in 1985, and Anderson received three nominations in 1985, 1986, and 1987. The series received three nominations for Outstanding Comedy Series in 1985, 1987, and 1988. The series also received many awards and nominations in the areas of lighting, editing, sound mixing, and technical direction. The show was nominated for 31 Emmys, winning seven.


title: Night Court

text: After its primary run in broadcast syndication, the series aired on cable's A&E Network for many years. It then aired on TV Land from 2005 to 2008, then began airing on Encore Classic on December 2, 2013. Beginning at the end of 2015, the show airs nationally on the Laff digital multicast subchannel.


title: Night Court

text: Network Ten first broadcast the series in the 1980s and 1990s. 7TWO began showing reruns in June 2011.


title: Night Court

text: Warner Home Video released the first three seasons on DVD in Region 1. Seasons 4–9 were released as Manufacture-on-Demand (MOD) DVDs as part of the Warner Archive Collection.


title: Night Court

text: The "Television Favorites" compilation DVD included the pilot episode, "All You Need Is Love"; both parts of the fourth-season finale, "Her Honor"; the fifth-season episodes "Death of a Bailiff" and "Who Was That Mashed Man?"; and the sixth-season episode "Fire", which marked the beginning of Harry's relationship with Christine.


title: Night Court

text: Harry Anderson, Markie Post, and Charles Robinson appeared in the "30 Rock" episode, "The One with the Cast of Night Court". John Larroquette is also mentioned; Harry says he had just spoken to John, which annoys Markie (who has not had recent contact with her absent former co-star) and begins an argument between them that lasts for most of the story.


title: Night Court

text: In December 2020, NBC announced it was working on a sequel series to "Night Court". The show will be executive produced by Melissa Rauch and Winston Rauch, with Dan Rubin to write. Larroquette is set to return as Fielding, while the show's central character will be Abby Stone, a judge and the daughter of Harry Stone. The show is expected to be produced by Warner Bros. Television for NBC. In April 2021, it was reported that Rauch will also lead the series as Abby Stone. In May 2021, it was announced that NBC had given a pilot order to a sequel series. In June 2021, Ana Villafañe joined the cast for the pilot, portraying an Assistant District Attorney and Lacretta will play a bailiff Donna "Gurgs" Gurganous. In July 2021, Kapil Talwalkar joined the cast for the pilot, will play a court's clerk Neil. In September 2021, it was announced that NBC had given the production a series order.


title: Punch-Drunk Love

text: Punch-Drunk Love is a 2002 American absurdist romantic comedy-drama film written and directed by Paul Thomas Anderson, and starring Adam Sandler, Emily Watson, Philip Seymour Hoffman, Luis Guzmán, and Mary Lynn Rajskub. It follows an entrepreneur with social anxiety who falls in love with his sister's co-worker.


title: Punch-Drunk Love

text: The film was produced by Revolution Studios and New Line Cinema, and distributed by Columbia Pictures. It features the video art of Jeremy Blake in the form of visual interludes. The film received positive reviews from critics, with Sandler's performance receiving widespread acclaim. However, the film was a box office bomb, failing to recoup its $25 million production budget at the box office.


title: Punch-Drunk Love

text: Barry Egan is a bachelor who owns a company that markets themed toilet plungers and other novelty items. He has seven overbearing sisters who regularly ridicule and emotionally abuse him, so he leads a lonely life punctuated by fits of rage and social anxiety. One day, he witnesses an inexplicable car accident, picks up an abandoned harmonium from the street, and encounters Lena Leonard (a coworker of Elizabeth, one of his sisters). Lena had orchestrated the meeting after seeing him in Elizabeth's family picture at work.


title: Punch-Drunk Love

text: Barry goes to his sister's birthday party, where they tease him about his sexuality, leading to a serious outburst in which he breaks his sister's sliding glass door. Afterwards, he asks his brother-in-law to refer him to a therapist. Instead, Barry calls a phone sex line to cope with his loneliness. The phone sex operator tries to extort money from him and then sends four henchmen, who are brothers, to collect. This complicates his budding relationship with Lena, as well as his plan to exploit a loophole in a Healthy Choice promotion and amass a million frequent-flyer miles by purchasing large quantities of pudding.


title: Punch-Drunk Love

text: When Lena leaves for Hawaii on a business trip, Barry decides to follow her, using his sister to find Lena, who is overjoyed to see him. As the two spend time together, Barry's sister calls Lena, complicating matters, but Lena lies about having contact with Barry. The romance develops further, leading to Barry's relief from his emotional isolation.


title: Punch-Drunk Love

text: On the return trip, the four brothers ram Barry's car, mildly injuring Lena. After fighting all four brothers off with a tire iron, Barry leaves Lena at the hospital and sets out to end the harassment. He calls the phone-sex line back and finds out the "supervisor" is the owner of a mattress store. Barry drives all the way to Provo, Utah, to confront the owner, Dean, face to face. At first, trying to intimidate Barry, Dean finds him more intimidating once he learns that Barry has come all the way from California. They both agree "that's that".


title: Punch-Drunk Love

text: Barry returns home and goes to see Lena to explain why the accident happened. He begs for forgiveness, pledging his loyalty and to use his frequent-flier miles to accompany her on all future business trips after his pudding miles are processed. Lena confesses she was more upset at being left at the hospital but forgives him and they embrace happily.


title: Punch-Drunk Love

text: After the success of "Magnolia" (1999), writer-director Paul Thomas Anderson stated that he was determined to make his next film ninety minutes long, and stated that he wanted to cast Adam Sandler in a future film. After establishing his style with his previous films, he wanted to challenge himself within the parameters of a ninety-minute-long romantic comedy. Anderson is a fan of Sandler's films, describing his love for his movies as "obsession-level," and was determined to make a film with Sandler as a lead, saying, "He's always just made me laugh, he gets me, I wanted a piece of him." He specifically wrote "Punch-Drunk Love" with Sandler and Emily Watson in mind. Anderson had to convince producer JoAnne Sellar, who was "befuddled" with his desire to cast Sandler, that he was the right person for the job. Anderson took inspiration for Barry Egan's characterization from watching the "Saturday Night Live: The Best of Adam Sandler" compilation DVD, primarily with the skit "The Denise Show," saying,


title: Punch-Drunk Love

text: Anderson described the film as an "art-house Adam Sandler film," while film critic Roger Ebert felt Anderson "deconstructed the Adam Sandler movies and put them back together again in a new way at a different level." In writing the elements of the Healthy Choice frequent-flier miles sub-plot line, Anderson was inspired by the real-life story of David Phillips, who successfully amassed over a million frequent flier miles from buying $3,000 worth of Healthy Choice's pudding. Anderson received approval from Phillips and Healthy Choice to adapt Phillips' story into the film. A major source of inspiration for "Punch-Drunk Love" came from the films of Jacques Tati, while Barry's blue suit was inspired by musicals such as "The Band Wagon" (1953) and "Singin' in the Rain" (1952)"."


title: Punch-Drunk Love

text: Filming and editing took place within over a year and a half due to several reasons, such as Anderson scrapping the first two weeks of shooting over fears that he was "making the same movie" as his previous filmography, as well as the threat of Hollywood strikes in 2001 that led to Sandler and Watson filming other projects in between filming "Punch-Drunk Love". Anderson also denied more funding from Revolution Studios, as he was determined to keep the film under $30 million in terms of budget.


title: Punch-Drunk Love

text: Sandler shared phone numbers with "Magnolia" star Tom Cruise when he visited "Saturday Night Live" during the taping of an episode hosted by Cruise's then-wife Nicole Kidman. While filming "Magnolia", Anderson contacted Sandler through a phone call with Cruise and expressed his intention to write a movie for him; despite being unfamiliar with Anderson, Sandler gave his blessing. Sandler was intimidated upon first viewing "Magnolia", leading him to be "fucking terrified" and doubt his ability to carry Anderson's next film. Anderson helped alleviate Sandler's fears upon personally being delivered the script. Sandler's casting was officially announced in November 2000; the unconventional pairing shocked reporters as Anderson was a filmmaker on the rise that wrote and directed critically-acclaimed films, while Sandler was known for negatively-reviewed mainstream comedies. Aside from the primary named cast, all on-screen actors are non-professionals, which Anderson found more interesting and less complicated.


title: Punch-Drunk Love

text: The score to "Punch-Drunk Love" was composed by Jon Brion. As with "Magnolia", Brion and Anderson collaborated heavily for the production of the film's score. However, rather than scoring the film after rough footage had been shot, Brion made compositions while making the film. During the scoring process, Brion would experiment with tones and sounds, carefully making note of what Anderson would respond to. Anderson himself would create the vocal tempos he would envision in the score and use them on set, even to the extent of inspiring the pace of Sandler's performance.


title: Punch-Drunk Love

text: The film's score features heavy use of the harmonium. Brion had introduced Anderson to it on "Magnolia", and Anderson knew he wanted it to feature heavily in the score. Many scenes between Sandler's character and the instrument were inspired by Brion. For instance, Brion once found a harmonium with a hole in its bellows before going on tour with Aimee Mann. To fix the problem, he covered the hole with duct tape. The situation is mirrored in the film.


title: Punch-Drunk Love

text: The film began a limited domestic release on October 11, 2002, grossing $118,539 from five theaters. It went on to gross $17.8 million in the United States, and an international total of $6.8 million, for a worldwide box office total of $24.6 million.


title: Punch-Drunk Love

text: On review aggregator Rotten Tomatoes, the film holds an approval rating of 79% based on 197 reviews, with an average rating of 7.40/10. The website's critical consensus states, "Odd, touching, and unique, "Punch-Drunk Love" is also delightfully funny, utilizing Adam Sandler's comic persona to explore the life of a lonely guy who finds love." On Metacritic, the film has a weighted average score of 78 out of 100, based on 37 critics, indicating "generally favorable reviews". Audiences polled by CinemaScore gave the film an average grade of "D+" on an A+ to F scale.


title: Punch-Drunk Love

text: Writing for "Rolling Stone", Peter Travers felt the pairing of Anderson and Sandler was "parallel lines that meet triumphantly in a mesmerizer that stays true to both of their anarchic spirits," and praised the cast's performances, ultimately calling the film's effect "intoxicating." Angie Errigo of "Empire" complimented Anderson's direction as "simply captivating and exquisitely controlled, with a restless mood and no end of fascinating, beautifully-orchestrated oddness," and said, "One of the joys of this film...is that you really have no idea what's going to happen next." Daniel Fierman of "Entertainment Weekly" thought the film was a "meditation on true love, the ways in which we are all bizarre, the magic of the perfect match, and the preposterously unlikely nature of the whole enterprise." The "Los Angeles Times"' Kenneth Turan stated that the film was "a comedy of discomfort and rage that turns unexpectedly sweet and pure." Writing for "Variety", Todd McCarthy said that "there is no mistaking the exceeding creativity that has gone into nearly every shot, transition, narrative choice and musical selection," and praised Adam Sandler, Emily Watson, and Philip Seymour Hoffman's performances. He also opined that "Sandler fans will probably take it as a lightweight, but agreeable enough, outing with slightly weird elements to it, while Anderson partisans could split between those who will revel in the thrill of his ongoing creative inventions and others who may find this light lifting between heavy workouts." Charles Taylor of "Salon.com" described the film as a "manic-depressive romantic comedy that aspires to the soul of a musical," and complimented Anderson's direction, Christopher Scarabosio's sound design, and Jon Brion's score. He believed that Anderson properly utilized the "threat of sudden, bellowing, red-faced rage" of Sandler's known comic persona in the film.


title: Punch-Drunk Love

text: David Ansen of "Newsweek" described the film as "a romantic comedy on the verge of a nervous breakdown," praising the film's unpredictability and cinematography, but felt Lena was underwritten, concluding that it was "an emotional jigsaw puzzle that's missing a couple of crucial pieces." Giving the film three stars out of five, Peter Bradshaw of "The Guardian" felt the story was "deeply unconvincing" and "a short cut to an entirely unearned emotional resolution that doesn't begin to illuminate the jagged and disturbing - and gripping - ideas that swirl around the beginning of this film," and felt the film's core romance was "the most bafflingly unreal love story you can imagine."


title: Punch-Drunk Love

text: Adam Sandler's lead performance received acclaim. Giving the film three-and-a-half stars out of four, Roger Ebert of the "Chicago Sun-Times" praised Sandler's performance in his review, saying, "Sandler, liberated from the constraints of formula, reveals unexpected depths as an actor. Watching this film, you can imagine him in Dennis Hopper roles. He has darkness, obsession and power. He can't go on making those moronic comedies forever, can he?" Errigo called the film "an anti-Adam Sandler movie that proves to be a highly defining moment for the actor" and called Sandler's performance "astonishing." She also felt Watson was "relishing a calming character who is on an even keel." "Entertainment Weekly"'s Owen Gleiberman said Sandler was "utterly winning to watch" and added that "he has become a tender and arresting presence, like a fusion of Chaplin’s Little Tramp, Woody Allen, and Edward Scissorhands." Desson Thomson of "The Washington Post" proclaimed that Sandler gave "the performance of his life" in the film.


title: Punch-Drunk Love

text: Sandler went on to win Best Actor at the Gijón International Film Festival for his performance and was also nominated for the Golden Globe Award for Best Actor – Motion Picture Musical or Comedy. Anderson won the award for Best Director at the 2002 Cannes Film Festival and the film was nominated for the Palme d'Or. The film was nominated for the Grand Prix of the Belgian Syndicate of Cinema Critics.


title: Punch-Drunk Love

text: The Criterion Collection released the film on Blu-ray in November 2016 with a restored HD transfer, the first time the company had done so for Anderson and Sandler. It has behind-the-scenes featurette about a recording session for the film's soundtrack, a Cannes press conference and deleted scenes.


title: Punch-Drunk Love

text: The film came in at #33 in The A.V. Club's "Top 50 films of the '00s". Filmmakers Lee Unkrich, Judd Apatow, Kleber Mendonça, Miranda July, Bong Joon-ho, Guillermo del Toro, Barry Jenkins and Taika Waititi, and actors Bill Nighy, Owen Wilson and Timothée Chalamet have cited it as one of their favorite films.


title: Punch-Drunk Love

text: When asked about "Punch-Drunk Love" following its twentieth anniversary in 2022, Sandler said that the film that enabled him to pursue films different from his usual roles, while also sharing that it helped forge a close friendship between him and Anderson. The two reunited in their first project since "Punch-Drunk Love" when Anderson helped film segments of Sandler's Netflix comedy special "100% Fresh" (2018)"."


title: Punch-Drunk Love

text: Critics agreed that "Punch-Drunk Love" remained as one of Sandler's best acting performances, and was a launchpad for Sandler to take on dramatic roles or opportunities outside of his usual mainstream comedies. In a retrospective review following its 2017 release on Netflix, "GQ"'s Miranda Popkey called the film "Adam Sandler’s finest performance and P.T. Anderson’s most underrated work," describing it as "a paean to love as a source of unfathomable power." "Far Out"'s Arun Starkey described "Punch-Drunk Love" as Sandler's "first true foray into auteur cinema" and "the first indicator of his prowess as an actor and shows that if he is given a good enough script that isn’t shackled by the tropes of a mainstream genre, he can actually do very well at carrying a three-dimensional character onto the big screen." Alan Dorich of "Comic Book Resources" shared that the film's critical success "changed the course of Sandler's career forever" and "opened new opportunities that enhanced his legacy as a performer," leading to other dramatic roles in films such as "Men, Women & Children" (2014), "The Meyerowitz Stories" (2017), and "Uncut Gems" (2019).


title: Defenestration

text: The term was coined around the time of an incident in Prague Castle in the year 1618 which became the spark that started the Thirty Years' War. This was done in "good Bohemian style", referring to the defenestration which had occurred in Prague's New Town Hall almost 200 years earlier (July 1419), which also on that occasion led to the Hussite war. The word comes from the New Latin "de-" ("down from") and "fenestra" (window or opening).


title: Defenestration

text: The term originates from two incidents in history, both occurring in Prague. In 1419, seven town officials were thrown from the New Town Hall, precipitating the Hussite War. In 1618, two Imperial governors and their secretary were tossed from the Prague Castle, sparking the Thirty Years' War. These incidents, particularly that in 1618, were referred to as the Defenestrations of Prague and gave rise to the term and the concept.


title: Defenestration

text: The word itself is derived from New Latin "defenestratio"; with "dē" meaning "out" + "fenestra" meaning "window" + "-atio" as a suffix indicating an action or process.


title: Defenestration

text: Historically, the word "defenestration" referred to an act of political dissent. Notably, the Defenestrations of Prague in 1419 and 1618 helped to trigger prolonged conflict within Bohemia and beyond. Some Catholics ascribed the survival of those defenestrated at Prague Castle in 1618 to divine intervention.


title: Defenestration

text: "Autodefenestration" (or "self-defenestration") is the term used for the act of jumping, propelling oneself, or causing oneself to fall, out of a window.


title: Duffer brothers

text: Matt and Ross Duffer (born February 15, 1984), often credited as the Duffer Brothers, are American film and television writers, directors, and producers. They are best known as the creators, directors and executive producers of the hit Netflix science fiction horror drama series "Stranger Things". They also wrote and directed the 2015 psychological horror film "Hidden", and wrote and produced episodes for the Fox mystery-science fiction series "Wayward Pines".


title: Duffer brothers

text: They are identical twin brothers and have had a close relationship since childhood. They work on all their projects as a pair.


title: Duffer brothers

text: After the brothers had written and directed several short films, their script for the post-apocalyptic horror film "Hidden" was acquired by Warner Bros. Pictures in 2011. The brothers would go on to direct the film "Hidden", which was released in 2015. Next the Duffer brothers were hired as writers/producers for the Fox television series "Wayward Pines".


title: Duffer brothers

text: With experience in television, they began pitching their idea for "Stranger Things", which Dan Cohen eventually brought to Shawn Levy. Backed by Levy's 21 Laps production company, the show was quickly picked up by Netflix. The show is set in 1980s Indiana and is an homage to 1980s pop culture, inspired and aesthetically informed by the works of Steven Spielberg, John Carpenter, Wes Craven, Sam Raimi, David Lynch, Stephen King, and George Lucas, among others.


title: Duffer brothers

text: It was released on July 15, 2016, to overwhelming praise, specifically for its characterization, pacing, atmosphere, acting, soundtrack, directing, writing, and homages to 1980s genre films. It began to develop a cult following online. Review aggregator Rotten Tomatoes gave the series an approval rating of 95%, based on 82 reviews, with a weighted average score of 7.96/10. The site's critical consensus states, "Exciting, heartbreaking, and sometimes scary, "Stranger Things" acts as an addictive homage to Spielberg films and vintage 1980s television."


title: Duffer brothers

text: On September 30, 2019, Netflix announced they had signed the Duffers for additional films and television shows over the coming years.


title: Duffer brothers

text: In March 2021, the duo announced they will team up with Spielberg to adapt Stephen King's and Peter Straub's "The Talisman" as a Netflix series. They will both be executive producers via Amblin Partners and Monkey Massacre and have hired Curtis Gwinn, who worked as a writer-executive producer on "Stranger Things", to act as writer and showrunner of the project.


title: Duffer brothers

text: Following the premiere of the fourth season of "Stranger Things" in July 2022, the Duffers launched the production company Upside Down Pictures, for which they offered Netflix several possible concepts for a follow up to the show. Among these include a live-action series adaption of "Death Note" and a series adaption of "The Talisman", in addition to their follow up series to "Stranger Things".


title: Duffer brothers

text: The Duffer Brothers were born and raised in Durham, North Carolina, the sons of Ann M. Christensen and Allen P. Duffer. They began making films in the third grade, using a Hi8 video camera that was a gift from their parents. They attended the Duke School for Children from grades K-8, a private suburban school, and then the Charles E. Jordan High School, a large Durham public school. They relocated to Orange, California, to study film at Chapman University's Dodge College of Film and Media Arts, where they graduated in 2007.


title: Duffer brothers

text: Ross Duffer married director Leigh Janiak in Palm Springs, California in December 2015. The couple met in 2006 at a production company in Los Angeles, where she was an assistant to the producer and he was an intern.


title: Ok Taec-yeon

text: Ok Taec-yeon (; born December 27, 1988), known mononymously as Taecyeon, is a South Korean rapper, singer, songwriter, actor and entrepreneur. He is the main rapper of the South Korean boy band 2PM.


title: Ok Taec-yeon

text: In 2010, Ok debuted as an actor in the Korean drama "Cinderella's Sister" and since then has starred in "Dream High" (2011), "Who Are You?" (2013), "Wonderful Days" (2014), "Assembly" (2015), "Let's Fight, Ghost" (2016), "Save Me" (2017), "" (2020), "Secret Royal Inspector & Joy" (2021) and "Vincenzo" (2021), as well as the movies "Marriage Blue" (2013) and "House of the Disappeared" (2017).


title: Ok Taec-yeon

text: Ok was born in Seoul, South Korea, but emigrated at the age of 10, with his parents and older sister Jihyen to Bedford, Massachusetts, a small town situated in the Greater Boston Area. It was his sister Jihyen who persuaded him to participate in a JYP Entertainment audition, whose promotion she had noticed when surfing on the Internet. After his reluctant agreement to participate, both headed for New York City on his 17th birthday. A week later he was chosen for the final 35 and got the call to go to South Korea to go further in the competition. At first Ok applied to become a model, but the judges suggested he try dancing and singing. Eventually he was named one of the dozen finalists (including his future members, Lee Junho and Hwang Chansung) to compete in the show "Superstar Survival", but was the first contestant to leave the show.


title: Ok Taec-yeon

text: Ok lived in Massachusetts for seven years, attending Bedford High School where he was a member of the Chess Club, Jazz Band, JV Soccer Team, and National Honor Society, before returning to pursue his career in Korea. Ok transferred to Young Dong High School in Seoul and then studied Business Administration at Dankook University and attended Korea University Graduate School of International Studies.


title: Ok Taec-yeon

text: He is fluent in English, Korean, and Japanese. Ok is also familiar with the use of the Busan dialect, which he used in the KBS2 drama "Wonderful Days".


title: Ok Taec-yeon

text: In 2008 he took part in Mnet's "Hot Blood Men" which follows the extreme training of 13 trainees in order to become a member of the boy band "One Day". "One Day" spawned two boy bands, 2AM and 2PM, the latter of which Ok became a member of. Six months after "Hot Blood" was aired on TV 2PM debuted with their first single "10 Points out of 10 Points" from their first EP Hottest Time of the Day, but it wasn't until their second EP "" that their success in the Korean music industry skyrocketed.


title: Ok Taec-yeon

text: Ok was featured in Baek Ji-young's 2009 hit song "My Ear's Candy". Baek revealed that she asked Ok to feature on the song after having listened to his rap on 2PM's single "10 Points out of 10 Points".


title: Ok Taec-yeon

text: In 2012, Ok teamed up with his fellow Dankook University alumni students to produce a digital album titled "Blue Bears with Taecyeon". The album was performed live at Dankook University for the matriculation ceremony. The title song “Wings” featured penned rap lyrics written by Ok. The second song, a remake of Lee Gwangjo's “A Night Like Tonight" was also included in the performance, with an original rap written by Ok himself. The album went on sale in February 2012, with all proceeds donated back the University.


title: Ok Taec-yeon

text: Ok released his first solo Japanese album "" in 2017. As part of the solo project, he successfully held his first solo concert, "Taecyeon (From 2PM) Premium Concert" at the Tokyo Dome City Hall in Japan on January 2–3.


title: Ok Taec-yeon

text: In July 2018, it was announced that Ok had signed an exclusive contract with 51K, an agency founded by actor So Ji-sub, following the end of his contract with JYP Entertainment. His former agency reported that he will remain as a member of 2PM despite the move.


title: Ok Taec-yeon

text: He formerly hosted SBS' music show "Inkigayo" with Wooyoung, and was a permanent cast member on "Family Outing 2" before it was cancelled.


title: Ok Taec-yeon

text: In 2010 he made his acting debut in KBS drama series "Cinderella's Sister" alongside Moon Geun-young and Chun Jung-myung. He then starred in high school drama "Dream High", which received high domestic ratings as well as international popularity.


title: Ok Taec-yeon

text: In September 2011, FujiTV announced that Ok was going to become a regular on their Sunday drama Boku to Star no 99 Nichi, along with Japanese actor Nishijima Hidetoshi and South Korean actress Kim Tae-hee. This is his first regular role on a Japanese drama.


title: Ok Taec-yeon

text: In February 2013, it was announced that Ok would form an on-screen couple with Taiwanese actress Emma Wu, in the Global Edition of the reality show "We Got Married". The same year, he made his film debut in romantic comedy "Marriage Blue". He composed two songs for the soundtrack of the film.


title: Ok Taec-yeon

text: In 2014, he starred in KBS' weekend drama "Wonderful Days", playing a tough-fisted bodyguard. The same year, he joined tvN's cooking variety show "Three Meals a Day" directed by Na PD. He later rejoined for a second season in 2015. Ok was praised for his hardworking image and easygoing personality on the show.


title: Ok Taec-yeon

text: In 2015, Ok was cast in KBS' political drama "Assembly". He plays an aspiring police officer who studies at the library to pass his entrance exams by day and works as an official's chauffeur by night.


title: Ok Taec-yeon

text: In 2016, he starred in horror comedy "Hey Ghost, Let's Fight" with Kim So-hyun, and featured in web-drama "First Seven Kisses" by Lotte Duty Free.


title: Ok Taec-yeon

text: In 2017, he starred in mystery thriller "House of the Disappeared" with veteran actress Kim Yunjin. He then starred in OCN's thriller drama "Save Me" alongside Seo Ye-ji.


title: Ok Taec-yeon

text: In 2020, he starred in the mystery drama "", reuniting with Lee Yeon-hee with whom he starred in the 2013 film "Marriage Blue". It was his first acting role since his military discharge.


title: Ok Taec-yeon

text: In 2021, he starred in the tvN drama, "Vincenzo" as the main antagonist. It was his first major antagonistic role since his debut in acting.


title: Ok Taec-yeon

text: In the same year, Ok also starred in the historical drama "Secret Royal Inspector & Joy", which premiered on both tvN and iQiyi in November 2021.


title: Ok Taec-yeon

text: In 2022, he played the role of Lim Jun-young, a Joseon spy who sneaks into the Japanese army camp in the war action film "", the second installment of Kim Han-min's "Yi Sun-sin trilogy".


title: Ok Taec-yeon

text: On December 9, 2010, a JYP spokesperson revealed that “Taec-yeon would like to give up his American permanent residence visa and recently, on December 1, he received his official confirmation for his permanent residence cancellation.”


title: Ok Taec-yeon

text: Ok had a physical examination for drafting but received a physical body status sufficient only for enlistment as public service personnel, due to his poor vision and a dislocated shoulder back in 2008. In 2012 and 2013, he underwent surgery to correct the disk as well as to remove pins in his upper arm from a serious break in 2013. He was cleared for active duty in December 2013 but delayed his enlistment due to busy workload.


title: Ok Taec-yeon

text: On September 4, 2017, Ok enlisted as an active duty soldier and began his mandatory military service. On October 18, he completed his basic military training and was placed at 9th Infantry Division in Gyeonggi Province as a military instruction assistant.


title: Ok Taec-yeon

text: In February 2018, Ok participated in various 2018 Winter Olympics events as one of the volunteers under the command of the Ministry of National Defense (South Korea). He hosted many cultural shows and concerts, and performed as a member of 2PM at the Olympic Headliner Show.


title: Ok Taec-yeon

text: On June 20, 2018, then-Prime Minister Lee Nak-yon recognized and praised Ok's efforts to enlist in active duty during his congratulatory speech at the 15th Exemplary Military Servicemen Awards, where Ok was hosting.


title: Ok Taec-yeon

text: On October 1, 2018, Ok led the future combat system demonstration in the 70th Armed Forces Day Celebration. The demonstration introduced the Warrior Platform program, which includes new and improved combat gear and equipment. One of the event officials stated, “Corporal Ok Taec-yeon gave up his American residency; he set a great example, as he received surgery for the discs in his back and accepted active duty despite the fact that he had previously approved for alternative service. He's currently faithfully continuing his military duties. We actively recommended him to participate in the Armed Forces Day event as we believed it would be meaningful for him.”


title: Ok Taec-yeon

text: Moreover, Ok ranked 1st on real time search engines as he also led the final salute to President Moon Jae-in.


title: Ok Taec-yeon

text: In February 2019, Ok received an early promotion as a Sergeant for his exceptional conduct while serving as a military instruction assistant at the 9th Armed Forces Division in Gyeonggi Province.


title: Ok Taec-yeon

text: Due to his superb records, exemplary character, and great performance, Ok was appointed as a 'Special Class Warrior' by his division commander, and was awarded as 'Model Soldier' by the Ministry of National Defense. He also earned the nickname ""Captain Korea"" from people online, because of his physique that mirrored the famous Marvel superhero, Captain America. The nickname has been used as headlines to describe the actor on many news portals and broadcasts. In one interview, Ok expressed the pressure of having the nickname, "It was a nickname that brought a lot of pressure but it also made me want to work that much harder. I'll continue to work hard to fit that nickname."


title: Ok Taec-yeon

text: In 2013, Ok hosted a 30-minute press conference on ustream to introduce "Okcat", a green-colored cat character to the public. Previously, Okcat emoticons have been released on the chat application KakaoTalk. During the conference, Ok told the history of his development of the character, and released his sketches to the public. The "Okcat" shop was opened on the same day, and featured a line of products with the image of the Okcat.


title: Honda B engine

text: The B-series are a family of inline four-cylinder DOHC automotive engines introduced by Honda in 1988. Sold concurrently with the D-series which were primarily SOHC engines designed for more economical applications, the B-series were a performance option featuring dual overhead cams along with the first application of Honda's VTEC system (available in some models). To identify a Honda B-series engine, the letter B is normally followed by two numbers to designate the displacement of the engine, another letter, and in US-spec engines, another number. The Japanese spec-engines are normally designated with a four character alphanumeric designation. The B-series, the B20B variant in particular, is not to be confused with the earlier Honda B20A engine introduced in 1985 and primarily available in the Prelude and Accord-derived vehicles from 1985 to 1991. While sharing some design elements and both being multivalve Honda four-cylinders, the B-series and B20A differ substantially in architecture, enough to be considered distinct engine families.


title: Honda B engine

text: They were made in , , , , and variants, with and without VTEC (Variable valve Timing and Electronic lift Control). Later models have minor upgrades including modifications to the intake valves and ports and piston tops, along with individual cylinder oil injectors (B18C models). They produce between and , with some models capable of a redline over 8500 RPM.


title: Honda B engine

text: Although it has many variations, the basic design differs very little among the B-Series. There are actually two short blocks which are used for the entire series. The distinction between them was the cylinder block deck height. The one used for B16 and B17 engines (except for B16B) has a deck height of while the short block used for B16B, B18 and B20 engines has a deck height of .


title: Honda B engine

text: Note: This engine uses the same block as the Integra Type R, which is taller than the B16A block, but with a crank the same stroke as the B16A. It uses longer rods to accommodate for this, which is why the Rod/Stroke ratio is higher than a standard B16. It is basically a ‘Destroked B18C Type R engine’


title: Honda B engine

text: The original Japanese B18A is not considered to be part of the modern B-series family, although it shares its dimensions with the later B18A1. This engine shares many characteristics with the B20A/B21 See Honda B20A engine.


title: Honda B engine

text: The B20A3 and B20A5 are the predecessor to the B family. All B-series engines were based from the B20A, but most engine components are not compatible. For more information, refer to the F3-series Honda race car that used a B20A engine. Also see Honda B20A engine.