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41-485: 1,1,1,2-Tetrafluoroethane (also known as norflurane ( INN ), R-134a, Klea 134a , Freon 134a , Forane 134a , Genetron 134a , Green Gas , Florasol 134a , Suva 134a , HFA-134a , or HFC-134a ) is a hydrofluorocarbon (HFC) and haloalkane refrigerant with thermodynamic properties similar to R-12 (dichlorodifluoromethane) but with insignificant ozone depletion potential and a lower 100-year global warming potential (1,430, compared to R-12's GWP of 10,900). It has

82-449: A bittering agent to deter people from inhaling the product. Some U.S. states, as well as the UK, have made laws regarding the abuse of gas dusters, as well as other inhalants, by criminalizing inhalant abuse or banning the sale of gas dusters and other inhalants to those under 18. Because of the generic name "canned air", it is mistakenly believed that the can only contains normal air or contains

123-711: A supercritical fluid . It is used in the resistive plate chamber particle detectors in the Large Hadron Collider . It is also used for other types of particle detectors, e.g. some cryogenic particle detectors . It can be used as an alternative to sulfur hexafluoride in magnesium smelting as a shielding gas . 1,1,1,2-Tetrafluoroethane was introduced in the early 1990s as a replacement for dichlorodifluoromethane (R-12) , which has massive ozone depleting properties. Even though 1,1,1,2-Tetrafluoroethane has insignificant ozone depletion potential ( ozone layer ) and negligible acidification potential ( acid rain ), it has

164-517: A 100-year global warming potential (GWP) of 1430 and an approximate atmospheric lifetime of 14 years. Its concentration in the atmosphere and contribution to radiative forcing have been growing since its introduction. Thus it was included in the IPCC list of greenhouse gases . R-134a began being phased out from use in the European Union , starting in the mid 2010s, by a directive of 2006, recommending

205-561: A branded medication may contain more than one drug. For example, the branded medications Celexa, Celapram and Citrol all contain the same active ingredient whose INN is citalopram . The antibacterial medication known as co-trimoxazole as well as those under the brand names Bactrim and Septran all contain two active ingredients easily recognisable by their INN: trimethoprim and sulfamethoxazole . The WHO publishes INNs in English, Latin , French, Russian, Spanish, Arabic , and Chinese , and

246-613: A drug's INNs are often cognate across most or all of the languages, with minor spelling or pronunciation differences, for example: paracetamol ( en ) paracetamolum ( la ), paracétamol ( fr ) and парацетамол ( ru ). An established INN is known as a recommended INN ( rINN ), while a name that is still being considered is called a proposed INN ( pINN ). National nonproprietary names such as British Approved Names (BAN), Dénominations Communes Françaises (DCF), Japanese Adopted Names (JAN) and United States Adopted Names (USAN) are nowadays, with rare exceptions, identical to

287-509: A less harmful substance (such as nitrous oxide , for example). However, the gases actually used are denser than air, such as difluoroethane . When inhaled, the gas displaces the oxygen in the lungs and removes carbon dioxide from the blood, which can cause the user to suffer from hypoxia . Contrary to popular belief, the majority of the psychoactive effects of these inhalants is not a result of oxygen deprivation. The euphoric feeling produced stems from cellular mechanisms that are dependent on

328-460: A pharmaceutical. To avoid confusion, which could jeopardize the safety of patients, trade-marks should neither be derived from INNs nor contain common stems used in INNs. WHO Each drug's INN is unique but may contain a stem that is shared with other drugs of the same class. In this context, a stem is a syllable (or syllables) created to evoke in the name the pharmacological mechanism of action or

369-601: A predictable spelling system, approximating phonemic orthography , is used, as follows: Many drugs are supplied as salts , with a cation and an anion. The way the INN system handles these is explained by the WHO at its "Guidance on INN" webpage. For example, amfetamine and oxacillin are INNs, whereas various salts of these compounds – e.g., amfetamine sulfate and oxacillin sodium – are modified INNs ( INNM ). Several countries had created their own nonproprietary naming system before

410-503: A refrigerant. However, the ban was lifted in Wisconsin in 2012. During the time that it was active, this Wisconsin-specific ban contained loopholes. For example, it was legal for a person to purchase gas duster containers with any amount of the chemical because in that instance the chemical is neither intended to be a refrigerant  nor is HFC-134a included in the § 7671a listing of class I and class II substances. Tetrafluoroethane

451-404: A unitary, hand-held compressed air dusting tool was filed in 1930 by E C Brown Co, listing Tappan Dewitt as the product's sole inventor. The patent application describes the product as a Single-unit, i.e. unitary, hand-held apparatus comprising a container and a discharge nozzle attached thereto, in which flow of liquid or other fluent material is produced by the muscular energy of the operator at

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492-554: A word to which inflectional affixes are added. INN stems employ the first definition, while under the more common alternative they would be described as roots. Pharmacology and pharmacotherapy (like health care generally) are universally relevant around the world, making translingual communication about them an important goal. An interlingual perspective is thus useful in drug nomenclature . The WHO issues INNs in English, Latin, French, Russian, Spanish, Arabic, and Chinese. A drug's INNs are often cognates across most or all of

533-503: Is a product used for cleaning or dusting electronic equipment and other sensitive devices that cannot be cleaned using water . This type of product is most often packaged as a can that, when a trigger is pressed, blasts a stream of compressed gas through a nozzle at the top. Despite the names "canned air" or "compressed air", the cans do not actually contain air (i.e. do not contain O 2 or N 2 gases) but rather contain other gases that are compressible into liquids. True liquid air

574-401: Is a separate issue from the global warming concern. True "air dusters" using ordinary air are also available in the market. These typically have much shorter run times than a chemical duster, but are easily refillable. Both hand pump and electric compressor models have been marketed. The maximum pressure for an aerosol can is typically 10 bar (145 psi) at 20   °C (68   °F). Therefore,

615-423: Is compressed into a liquid, which upon vaporization absorbs a significant amount of thermal energy . As a result, it will greatly lower the temperature of any object it contacts as it evaporates. For its medical uses, 1,1,1,2-tetrafluoroethane has the generic name norflurane. It is used as propellant for some metered dose inhalers . It is considered safe for this use. In combination with pentafluoropropane , it

656-427: Is not desired. When using gas duster, it is recommended to not hold the can upside down, as this can result in spraying liquid on to the surface. The liquid, when released from the can, boils at a very low temperature, rapidly cooling any surface it touches. This can cause mild to moderate frostbite on contact with skin, especially if the can is held upside down. Also, the can gets very cold during extended use; holding

697-522: Is not practical, as it cannot be stored in metal spray cans due to extreme pressure and temperature requirements. Common duster gases include hydrocarbon alkanes , like butane , propane , and isobutane , and hydrofluorocarbons like 1,1-difluoroethane , 1,1,1-trifluoroethane , or 1,1,1,2-tetrafluoroethane which are used because of their lower flammability. When inhaled, gas duster fumes may produce psychoactive effects and may be harmful to health, sometimes even causing death. The first patent for

738-536: Is typically made by reacting trichloroethylene with hydrogen fluoride : It reacts with butyllithium to give trifluorovinyl lithium: Mixtures with air of the gas 1,1,1,2-tetrafluoroethane are not flammable at atmospheric pressure and temperatures up to 100 °C (212 °F). However, mixtures with high concentrations of air at elevated pressure and/or temperature can be ignited . Contact of 1,1,1,2-tetrafluoroethane with flames or hot surfaces in excess of 250 °C (482 °F) may cause vapor decomposition and

779-433: Is used as a topical vapocoolant spray for numbing boils before curettage . It has also been studied as a potential inhalational anesthetic , but it is nonanaesthetic at doses used in inhalers. International Nonproprietary Name Having unambiguous standard names for each pharmaceutical substance ( standardization of drug nomenclature ) is important because a drug may be sold under many different brand names, or

820-551: The Intergovernmental Panel on Climate Change (IPCC), the global warming potential (GWP) of HFC-152a, HFC-143a, and HFC-134a are 124, 4470, and 1430, respectively. GWP refers to global warming effect in comparison to CO 2 for unit mass. 1 kg of HFC-152a is equivalent to 124 kg of CO 2 . Gas dusters sold in many countries are ozone safe as they use "zero ODP" (zero ozone depletion potential ) gases. For example, tetrafluoroethane has insignificant ODP. This

861-503: The Stem Book . Some examples of stems are: The School of INN is a WHO International Nonproprietary Name Programme initiative launched in 2019, which aims to provide information to pharmacy, medical and health students, as well as health professionals and other stakeholders on how an INN is designed and constructed. Users can take self-administered courses on several topics using this free and open source learning platform. For example,

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902-455: The Stem in a pill course, in which each topic or course contains information correlating INN and pharmacology for a given stem, including indications , mechanism of action , pharmacokinetics , contraindications , and drug interactions for the drugs sharing the stem. There is also a "How to ..." section about INN Programme services and MedNet INN which enables users to carry out searches in

943-436: The "same word" principle allows health professionals and patients who do not speak the same language to communicate to some degree and to avoid potentially life-threatening confusions from drug interactions. To facilitate the translation and pronunciation of INN, "f" should be used instead of "ph", "t" instead of "th", "e" instead of "ae" or "oe", and "i" instead of "y"; the use of the letters "h" and "k" should be avoided. Thus

984-436: The "same word". Although Ибупрофе́н ( ru ) and ibuprofen ( en ) have a transliteration difference, they sound similar, and for Russian speakers who can recognize Latin script or English speakers who can recognize Cyrillic script , they look similar; users can recognize the "same word". Thus, INNs make medicines bought anywhere in the world as easily identifiable as possible to people who do not speak that language. Notably,

1025-558: The INN database to retrieve information on INN, its chemical information and ATC codes amonsgt other things. The School of INN has created pilot sites in collaboration with several Universities around the globe: University of the Western Cape (South Africa), University of Eastern Piedmont (Italy), Université Grenoble Alpes (France) and University Ramon Lull and University of Alcalá in Spain. These pilot sites are involved in disseminating

1066-534: The INN was created, and in many cases, the names created under the old systems continue to be used in those countries. As one example, in English the INN name for a common painkiller is paracetamol ; the table below gives the alternative names for this in different systems: Other naming systems not listed above include France 's Dénomination Commune Française (DCF) and Italy 's Denominazione Comune Italiana (DCIT). Gas duster A gas duster , also known as tinned wind , compressed air , or canned air ,

1107-417: The INN. Mandate The World Health Organization has a constitutional mandate to "develop, establish and promote international standards with respect to biological, pharmaceutical and similar products". The World Health Organization collaborates closely with INN experts and national nomenclature committees to select a single name of worldwide acceptability for each active substance that is to be marketed as

1148-462: The United States no longer use R-134a. California may also prohibit the sale of canned R-134a to individuals to avoid non-professional recharge of air conditioners. A ban had been in place in Wisconsin since October 1994 under ATCP 136 prohibiting sales of container sizes holding less than 15 lbs of 1,1,1,2-tetrafluoroethane, but this restriction applied only when the chemical was intended to be

1189-495: The can itself can result in cold burns. A dust spray can often be used as a freeze spray . Many gas dusters contain HFC-134a (tetrafluoroethane), which is widely used as a propellant and refrigerant. HFC-134a sold for those purposes is often sold at a higher price, which has led to the practice of using gas dusters as a less expensive source of HFCs for those purposes. Adapters have been built for such purposes, although in most cases,

1230-429: The chemical structure of the substance. Stems are mostly placed word-finally (suffixes), but in some cases word-initial stems (prefixes) are used. For example, the beta blocker drugs propranolol and atenolol share the stem -olol (as a suffix ), and the benzodiazepine drugs lorazepam and diazepam share the stem -azepam (also a suffix) The list of stems in use are collected in a publication informally known as

1271-455: The course An Introduction to Drug Nomenclature and INN provides the user with a general overview of drug nomenclature and how INN are obtained and constructed. The course Learning Clinical Pharmacology (ATC classification, INN system) provides the student with the first steps to learn pharmacology using INN stems . Registered students can take other courses provided by the School of INN, such as

1,1,1,2-Tetrafluoroethane - Misplaced Pages Continue

1312-419: The early 1990s as a replacement for the more environmentally harmful R-12 . Retrofit kits are available to convert units that were originally R-12-equipped. Other common uses include plastic foam blowing, as a cleaning solvent, a propellant for the delivery of pharmaceuticals (e.g., inhaler canisters such as for bronchodilators ), wine cork removers, gas dusters ("canned air"), and in air driers for removing

1353-651: The emission of toxic gases including hydrogen fluoride and carbonyl fluoride , however the decomposition temperature has been reported as above 370 °C. 1,1,1,2-Tetrafluoroethane itself has an LD 50 of 1,500 g/m in rats, making it relatively non-toxic, apart from the dangers inherent to inhalant abuse . Its gaseous form is denser than air and will displace air in the lungs. This can result in asphyxiation if excessively inhaled. This contributes to most deaths by inhalant abuse . Aerosol cans containing 1,1,1,2-tetrafluoroethane, when inverted, become effective freeze sprays. Under pressure, 1,1,1,2-tetrafluoroethane

1394-517: The formula CF 3 CH 2 F and a boiling point of −26.3 °C (−15.34 °F) at atmospheric pressure. R-134a cylinders are colored light blue . A phaseout and transition to HFO-1234yf and other refrigerants, with GWPs similar to CO 2 , began in 2012 within the automotive market. 1,1,1,2-Tetrafluoroethane is a non-flammable gas used primarily as a "high-temperature" refrigerant for domestic refrigeration and automobile air conditioners . These devices began using 1,1,1,2-tetrafluoroethane in

1435-440: The languages, but they also allow small inflectional , diacritic , and transliterational differences that are usually transparent and trivial for nonspeakers (as is true of most international scientific vocabulary ). For example, although ibuprofenum ( la ) has an inflectional difference from ibuprofen ( en ), and although ibuprofène ( fr ) has a diacritic difference, the differences are trivial; users can easily recognize

1476-408: The moisture from compressed air . 1,1,1,2-Tetrafluoroethane has also been used to cool computers in some overclocking attempts. It is the refrigerant used in plumbing pipe freeze kits. It is also commonly used as a propellant for airsoft airguns. The gas is often mixed with a silicone-based lubricant. 1,1,1,2-Tetrafluoroethane is also being considered as an organic solvent , both as a liquid and

1517-650: The molecular structure of the specific inhalant, as is the case with all psychoactive drugs. Their exact mechanisms of action have not been well elucidated, but it is hypothesized that they have much in common with that of alcohol . This type of inhalant abuse can cause a plethora of negative effects including brain and nerve damage, paralysis , serious injury, or death. Since gas dusters are often contained in pressure vessels , they are considered explosively volatile . Difluoroethane (HFC-152a), trifluoroethane (HFC-143a), and completely non-flammable tetrafluoroethane (HFC-134a) are potent greenhouse gases. According to

1558-496: The moment of use or by an equivalent manipulator independent from the apparatus the spray being effected by a gas or vapour flow from a source where the gas or vapour is not in contact with the liquid or other fluent material to be sprayed, e.g. from a compressible bulb, an air pump or an enclosure surrounding the container designed for spraying particulate material. Gas duster can be used for cleaning dust off surfaces such as keyboards, as well as sensitive electronics in which moisture

1599-472: The replacement of gases in air conditioning systems with a GWP above 100. 1,1,1,2-tetrafluoroethane is subject to use restrictions in the US and other countries as well. The Society of Automotive Engineers (SAE) has proposed that it be best replaced by a new fluorochemical refrigerant HFO-1234yf (CF 3 CF=CH 2 ) in automobile air-conditioning systems. As of model year 2021, newly manufactured light-duty vehicles in

1640-404: The use of INN, teaching based on INN and related research activities. The term stem is not used consistently in linguistics . It has been defined as a form to which affixes (of any type) can be attached. Under a different and apparently more common view, this is the definition of a root , while a stem consists of the root plus optional derivational affixes, meaning that it is the part of

1681-456: The use of such adapters will void the warranty on the equipment they are used with. One example of this practice is the case of airsoft gas guns, which use HFC-134a as the compressed gas. Several vendors sell "duster adapters" for use with airsoft guns, though it is necessary to add a lubricant when using gas dusters to power airsoft guns . Since gas dusters are one of the many inhalants that can be easily abused, many manufacturers have added

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