The Significant New Alternatives Policy (also known as Section 612 of the Clean Air Act or SNAP , promulgated at 40 CFR part 82 Subpart G) is a program of the EPA to determine acceptable chemical substitutes, and establish which are prohibited or regulated by the EPA. It also establishes a program by which new alternatives may be accepted, and promulgates timelines to the industry regarding phase-outs of substitutes.
23-458: Originally, Section 612 was limited by ozone-depleting chemicals. However, after passing regulations to phase-out R134a , an HFC refrigerant with no ozone-depleting potential, this phase-out was defended by a subsidiary of DuPont siding with the EPA as it was challenged by a major manufacturer of R134a, and was struck down in 2017. This decision was upheld in 2018. In 2021, a new law was passed as part of
46-599: A refrigerant and aerosol spray propellant . In compliance with the Montreal Protocol , its manufacture was banned in developed countries (non-article 5 countries) in 1996, and in developing countries (Article 5 countries) in 2010 out of concerns about its damaging effect on the ozone layer . Its only allowed usage is as a fire retardant in submarines and aircraft. It is soluble in many organic solvents . R-12 cylinders are colored white. It can be prepared by reacting carbon tetrachloride with hydrogen fluoride in
69-471: 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 a 100-year global warming potential (GWP) of 1430 and an approximate atmospheric lifetime of 14 years. Its concentration in
92-399: 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 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
115-464: A complete submittal, the EPA requires reports on: One important, changing aspect of SNAP is its effect on the HVAC industry. Particularly because it decides which refrigerants may be legally used, it coordinates refrigerant phaseouts in the U.S., and which are prohibited against venting in concordance with Section 608 . The following is a list of accepted refrigerants, or phase-out periods according to
138-418: A lower 100-year global warming potential (1,430, compared to R-12's GWP of 10,900). It has 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
161-408: A team that included Thomas Midgley Jr. , Albert Leon Henne , and Robert McNary. From 1930 to 1935, they developed dichlorodifluoromethane (CCl 2 F 2 or R12), trichlorofluoromethane (CCl 3 F or R11), chlorodifluoromethane (CHClF 2 or R22), trichlorotrifluoroethane (CCl 2 FCClF 2 or R113), and dichlorotetrafluoroethane (CClF 2 CClF 2 or R114), through Kinetic Chemicals which
184-408: 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 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
207-591: 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 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
230-427: 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
253-400: Is not compatible with R-134a. Some oils designed for conversion to R-134a are advertised as compatible with residual R-12 mineral oil. Illegal replacements for R-12 include highly flammable hydrocarbon blends such as HC-12a , the flammability of which has caused injuries and deaths. Aside from its environmental impacts, R12, like most chlorofluoroalkanes, forms phosgene gas when exposed to
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#1732852455158276-422: 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. Dichlorodifluoromethane Dichlorodifluoromethane ( R-12 ) is a colorless gas popularly known by the genericized brand name Freon (as Freon-12 ). It is a chlorofluorocarbon halomethane (CFC) used as
299-422: The EPA. R134a 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
322-820: 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 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
345-499: The appropriations bill extending the EPA's scope to substances with high GWP as well. The EPA looks at available chemical substitutes in the following industrial sectors: Evaluations are ongoing as technological understanding improves, and can only prohibit substance where the EPA has determined other available substitutes that pose less overall risk to human health and the environment. In order to submit new proposed chemicals, along with general contact and marketing information, for
368-529: 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 the replacement of gases in air conditioning systems with a GWP above 100. 1,1,1,2-tetrafluoroethane is subject to use restrictions in
391-404: The chemical was intended to be 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
414-656: 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
437-649: The highest ozone depletion potential among chlorocarbons due to the presence of 2 chlorine atoms in the molecule. R-12 also has intense global warming potential (GWP) with the 20yr, 100yr and 500yr GWP being 11400, 11200 and 5100 times greater than CO 2 . R-12 was used in most refrigeration and vehicle air conditioning applications prior to 1994 before being replaced by 1,1,1,2-tetrafluoroethane (R-134a), which has an insignificant ozone depletion potential . Automobile manufacturers began phasing in R-134a around 1993 . When older units leak or require repair involving removal of
460-416: The presence of a catalytic amount of antimony pentachloride : This reaction can also produce trichlorofluoromethane (CCl 3 F), chlorotrifluoromethane (CClF 3 ) and tetrafluoromethane (CF 4 ). Charles F. Kettering , vice president of General Motors Research Corporation, was seeking a refrigerant replacement that would be colorless, odorless, tasteless, nontoxic, and nonflammable. He assembled
483-408: The refrigerant, retrofitment to a refrigerant other than R-12 (most commonly R-134a) is required in some jurisdictions. The United States does not require such conversion. Retrofitment requires a system flush and a new filter/dryer or accumulator, and may also involve the installation of new seals and/or hoses made of materials compatible with the refrigerant being installed. Mineral oil used with R-12
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#1732852455158506-621: The § 7671a listing of class I and class II substances. Tetrafluoroethane 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
529-483: Was a joint venture between DuPont and General Motors . The use of chlorofluorocarbons as aerosols in medicine, such as USP -approved salbutamol , has been phased out by the U.S. Food and Drug Administration . A different propellant known as hydrofluoroalkane , or HFA, which was not known to harm the environment, was chosen to replace it. That being said it still listed on the FDA's approved food additive list. R-12 has
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