Editing Refrigerant (section)

=== Phasing out of CFCs ===
{{See also|Montreal Protocol}}
In the mid-1970s, scientists discovered that CFCs were causing major damage to the [[ozone layer]] that protects the earth from ultraviolet radiation, and to the [[ozone hole]]s over polar regions.<ref>{{cite journal |last1=Molina |first1=Mario J. |last2=Rowland |first2=F. S |title=Stratospheric sink for chlorofluoromethanes: chlorine catalysed destruction of ozone |journal=Nature |date=28 June 1974 |volume=249 |pages=810–812 |doi=10.1038/249810a0 |url=https://courses.seas.harvard.edu/climate/eli/Courses/EPS281r/Sources/Ozone-hole/2-Molina-Rowland-1974.pdf |access-date=October 6, 2024}}</ref><ref>{{cite book |last1=National Research Council |title=Halocarbons: Effects on Stratospheric Ozone |date=1976 |publisher=The National Academies Press |location=Washington, DC |doi=10.17226/19978 |isbn=978-0-309-02532-4 |url=https://nap.nationalacademies.org/catalog/19978/halocarbons-effects-on-stratospheric-ozone |access-date=October 6, 2024}}</ref> This led to the signing of the [[Montreal Protocol]] in 1987 which aimed to phase out CFCs and HCFC<ref>{{cite web |access-date=27 July 2023 |date=1 July 2011|title=Air Conditioners, Dehumidifiers, and R-410A Refrigerant |url=https://www.sylvane.com/blog/air-conditioners-dehumidifiers-r-410-a-refrigerant/|website=Sylvane}}</ref> but did not address the contributions that HFCs made to climate change. The adoption of HCFCs such as [[Chlorodifluoromethane|R-22]],<ref>{{Cite web|url=https://books.google.com/books?id=zMYRAAAAIAAJ&dq=r+22+replaced+r+12&pg=RA1-PA589|title=Clean Air Act Amendments of 1987: Hearings Before the Subcommittee on Environmental Protection of the Committee on Environment and Public Works, United States Senate, One Hundredth Congress, First Session, on S. 300, S. 321, S. 1351, and S. 1384 ...|first=United States Congress Senate Committee on Environment and Public Works Subcommittee on Environmental|last=Protection|date=May 14, 1987|publisher=U.S. Government Printing Office|via=Google Books}}</ref><ref>{{Cite book|url=https://books.google.com/books?id=5AGjDf5QkfwC&pg=PA179 |page=179 |title=Fluorinated Hydrocarbons—Advances in Research and Application |edition=2013 |date=June 21, 2013 |publisher=ScholarlyEditions |isbn=9781481675703 |via=Google Books}}</ref><ref>{{Cite book|url=https://books.google.com/books?id=zeYGAAAAQBAJ&pg=PA171 |page=171 |title=Refrigeration and Air Conditioning Technology |first1=Bill |last1=Whitman |first2=Bill |last2=Johnson |first3=John |last3=Tomczyk |first4=Eugene |last4=Silberstein |date=February 25, 2008 |publisher=Cengage Learning |isbn=978-1111803223 |via=Google Books}}</ref> and R-123<ref name="cool" /> was accelerated and so were used in most U.S. homes in air conditioners and in [[chiller]]s<ref>{{Cite web |url=https://ec.europa.eu/clima/sites/clima/files/docs/0007/mcquay_hfc_scroll_chillers_paper_en.pdf |title=Scroll Chillers: Conversion from HCFC-22 to HFC-410A and HFC-407C |access-date=2021-03-29 |archive-date=2021-07-20 |archive-url=https://web.archive.org/web/20210720201831/https://ec.europa.eu/clima/sites/clima/files/docs/0007/mcquay_hfc_scroll_chillers_paper_en.pdf |url-status=dead }}</ref> from the 1980s as they have a dramatically lower [[Ozone depletion potential|Ozone Depletion Potential]] (ODP) than CFCs, but their ODP was still not zero which led to their eventual phase-out.

[[Hydrofluorocarbon]]s (HFCs) such as [[R-134a]],<ref>{{Cite web|url=https://www.achrnews.com/articles/135112-whats-happening-with-r-134a|title=What's Happening With R-134a? &#124; 2017-06-05 &#124; ACHRNEWS &#124; ACHR News|website=achrnews.com}}</ref><ref>{{cite web |url=https://www.techtips.ie/Hella-Ireland/aircon-conversion-r12r134a.pdf |date=1 October 2005 |access-date=27 July 2023 |title=Conversion R12/R134a |work=Behr Hella Service GmbH }}</ref> [[R-407A]],<ref>{{Cite press release |url=https://www.achrnews.com/articles/110226-r-407a-gains-snap-ok |date=22 June 2009 |title=R-407A Gains SNAP OK |website=achrnews.com }}</ref> [[R-407C]],<ref>{{Cite web|url=https://www.achrnews.com/articles/110377-june-26-2009-emerson-approves-r-407a-r-407c-for-copeland-discus-compressors?v=preview|title=June 26, 2009: Emerson Approves R-407A, R-407C for Copeland Discus Compressors|website=achrnews.com}}</ref> [[R-404A]],<ref name="achr">{{Cite web |date=1 May 2017 |first=John |last=Tomczyk |url=https://www.achrnews.com/articles/134928-whats-the-latest-with-r-404a|title=What's the Latest with R-404A?|website=achrnews.com}}</ref> [[R-410A]]<ref>{{Cite web|url=https://www.achrnews.com/articles/84438-taking-new-refrigerants-to-the-peak?v=preview|title=Taking New Refrigerants to the Peak|website=achrnews.com}}</ref> (a 50/50 blend of [[R-125]]/[[Difluoromethane|R-32]]) and R-507<ref>{{cite web | url=https://www.osti.gov/etdeweb/biblio/167601 | title=R502/R22 - replacement refrigerant R507 in commercial refrigeration; R502/R22 - Ersatzkaeltemittel R507 in der Gewerbekuehlung. Anwendungstechnik - Kaeltemittel | date=31 December 1995 | last1=Koenig | first1=H. }}</ref><ref>{{cite web | url=https://www.osti.gov/biblio/211821 | osti=211821 | title=System performance comparison of R-507 with R-502 | date=31 December 1995 | last1=Linton | first1=J. W. | last2=Snelson | first2=W. K. | last3=Triebe | first3=A. R. | last4=Hearty | first4=P. F. }}</ref> were promoted as replacements for CFCs and HCFCs in the 1990s and 2000s. HFCs were not ozone-depleting but did have [[global warming potential]]s (GWPs) thousands of times greater than CO<sub>2</sub> with atmospheric lifetimes that can extend for decades. This in turn, starting from the 2010s, led to the adoption in new equipment of Hydrocarbon and HFO ([[hydrofluoroolefin]]) refrigerants R-32,<ref>{{Cite web|url=https://www.coolingpost.com/world-news/daikin-reveals-details-of-r32-vrv-air-conditioner/|title=Daikin reveals details of R32 VRV air conditioner|date=6 February 2020|website=Cooling Post}}</ref> R-290,<ref name="auto">{{Cite web|url=https://www.coolingpost.com/world-news/refrigerant-blends-to-challenge-hydrocarbon-efficiencies/|title=Refrigerant blends to challenge hydrocarbon efficiencies|date=22 December 2019|website=Cooling Post}}</ref> R-600a,<ref name="auto"/> [[R-454B]],<ref>{{Cite web|url=https://www.achrnews.com/articles/144613-an-hvac-technicians-guide-to-r-454b?v=preview|title=An HVAC Technician's Guide to R-454B|website=achrnews.com}}</ref> [[R-1234yf]],<ref>{{cite web |url=https://autoexpert.com.au/posts/the-truth-about-new-automotive-ac-refrigerant-r1234yf |title=The truth about new automotive A/C refrigerant R1234YF | date=25 July 2018 }}</ref><ref>{{cite journal |url=https://docs.lib.purdue.edu/cgi/viewcontent.cgi?article=2524&context=iracc |last=Kontomaris |first=Konstantinos |title=HFO-1336mzz-Z: High Temperature Chemical Stability and Use as A Working Fluid in Organic Rankine Cycles |year=2014 |journal=International Refrigeration and Air Conditioning Conference |quote=Paper 1525}}</ref> R-514A,<ref>{{Cite web|url=https://www.coolingpost.com/world-news/trane-adopts-new-low-gwp-refrigerant-r514a/|title=Trane adopts new low GWP refrigerant R514A|date=15 June 2016|website=Cooling Post}}</ref> R-744 ({{CO2}}),<ref>{{Cite web|url=https://www.coolingpost.com/features/r404a-the-alternatives/|title=R404A – the alternatives|date=26 February 2014|website=Cooling Post}}</ref> [[R-1234ze(E)]]<ref>{{Cite web|url=https://www.coolingpost.com/products/carrier-expands-r1234ze-chiller-range/|title=Carrier expands R1234ze chiller range|date=20 May 2020|website=Cooling Post}}</ref> and [[1-Chloro-3,3,3-trifluoropropene|R-1233zd(E)]],<ref>{{Cite web|url=https://www.coolingpost.com/world-news/carrier-confirms-an-hfo-refrigerant-future/|title=Carrier confirms an HFO refrigerant future|date=5 June 2019|website=Cooling Post}}</ref> which have both an ODP of zero and a lower GWP. Hydrocarbons and {{CO2}} are sometimes called natural refrigerants because they can be found in nature.

The environmental organization [[Greenpeace]] provided funding to a former East German refrigerator company to research alternative ozone- and climate-safe refrigerants in 1992. The company developed a hydrocarbon mixture of [[propane]] and [[isobutane]], or pure isobutane,<ref>{{Cite web |title=Greenfreeze: A revolution in domestic refrigeration |url=https://www.ecomall.com/greenshopping/greenfreeze.htm |access-date=2022-07-04 |website=ecomall.com}}</ref> called "Greenfreeze", but as a condition of the contract with Greenpeace could not patent the technology, which led to widespread adoption by other firms.<ref name="greenpeace.org">{{cite web|title=Happy birthday, Greenfreeze! |date=25 March 2013 |url=http://p3-raw.greenpeace.org/international/en/news/Blogs/makingwaves/happy-birthday-greenfreeze/blog/44473/ |work=Greenpeace|archive-url=https://web.archive.org/web/20200408034609/http://p3-raw.greenpeace.org/international/en/news/Blogs/makingwaves/happy-birthday-greenfreeze/blog/44473/ |access-date=8 June 2015|archive-date=2020-04-08 }}</ref><ref name="ozone.unep.org">{{cite web|title=Ozone Secretariat |url= http://ozone.unep.org/Events/4C1_PublicInfo_Awards97.shtml|archive-url =http://webarchive.loc.gov/all/20150412225008/http://ozone.unep.org/Events/4C1_PublicInfo_Awards97.shtml |url-status=dead|archive-date=12 April 2015|publisher=United Nations Environment Programme}}</ref><ref name=Spiegel>{{cite news|last=Gunkel|first=Christoph|title=Öko-Coup aus Ostdeutschland|url= http://www.spiegel.de/einestages/oeko-revolution-aus-ostdeutschland-wie-foron-den-ersten-fckw-freien-kuehlschrank-der-welt-erfand-a-951064.html |date=13 September 2013|work=Der Spiegel |language=de|access-date=4 September 2015}}</ref> Policy and political influence by corporate executives resisted change however,<ref>{{cite journal |doi=10.1111/1467-9388.00275 |title=Making a Difference: A Case Study of the Greenpeace Ozone Campaign |year=2001 |last1=Maté |first1=John |journal=Review of European Community & International Environmental Law |volume=10 |issue=2 |pages=190–198 }}</ref><ref>Benedick, Richard Elliot Ozone Diplomacy Cambridge, MA: Harvard University 1991.</ref> citing the flammability and explosive properties of the refrigerants,<ref>{{Cite web |last=Honeywell International, Inc. |date=2010-07-09 |title=Comment on EPA Proposed Rule Office of Air and Radiation Proposed Significant New Alternatives Policy (SNAP) Protection of Stratospheric Ozone: Listing of Substitutes for Ozone-Depleting Substances – Hydrocarbon Refrigerants |url=https://downloads.regulations.gov/EPA-HQ-OAR-2009-0286-0170/attachment_1.pdf}}</ref> and [[DuPont]] together with other companies blocked them in the U.S. with the U.S. EPA.<ref name="ReferenceA">{{cite web|url=http://www.greenpeace.org/brasil/pt/Noticias/discurso-de-frank-guggenheim-n/|title=Discurso de Frank Guggenheim no lançamento do Greenfreeze &#124; Brasil|website=Greenpeace.org|access-date=10 June 2015|archive-date=24 September 2015|archive-url=https://web.archive.org/web/20150924024715/http://www.greenpeace.org/brasil/pt/Noticias/discurso-de-frank-guggenheim-n/|url-status=dead}}</ref><ref>{{cite web|url= https://www.greenpeace.de/themen/klimawandel/klimaschutz/der-greenfreeze-endlich-den-usa-angekommen|title=Der Greenfreeze - endlich in den USA angekommen|language=de |website=Greenpeace.de|date=28 December 2011|access-date=10 June 2015}}</ref>

Beginning on 14 November 1994, the [[Federal government of the United States|U.S.]] [[United States Environmental Protection Agency|Environmental Protection Agency]] restricted the sale, possession and use of refrigerants to only licensed technicians, per rules under sections 608 and 609 of the Clean Air Act.<ref>{{cite web|url= http://www.epa.gov/ozone/title6/608/608fact.html |title=Complying With The Section 608 Refrigerant Recycling Rule &#124; Ozone Layer Protection - Regulatory Programs |website=Epa.gov |date=21 April 2015|access-date=10 June 2015}}</ref> In 1995, Germany made CFC refrigerators illegal.<ref name="ecomall.com">{{cite web|title= Greenfreeze: a Revolution in Domestic Refrigeration|url= http://www.ecomall.com/greenshopping/greenfreeze.htm |website=ecomall.com |access-date=8 June 2015}}</ref>

In 1996 [[Eurammon]], a European non-profit initiative for [[natural refrigerant]]s, was established and comprises European companies, institutions, and industry experts.<ref name="about">{{Cite web|url=http://www.eurammon.com/about-eurammon|title=Company background|access-date=2021-03-15|archive-date=2020-02-20|archive-url=https://web.archive.org/web/20200220124551/http://www.eurammon.com/about-eurammon|url-status=dead}}</ref><ref>{{cite report |publisher=IPCC/TEAP |title=Safeguarding the ozone layer and the global climate System: issues related to Hydrofluorocarbons and Perfluorocarbons |year=2005 |url=https://www.ipcc.ch/report/safeguarding-the-ozone-layer-and-the-global-climate-system/ }}</ref><ref>{{cite journal |url=https://www.science.org/doi/10.1126/science.289.5477.270 |doi=10.1126/science.289.5477.270 |title=Causes of Climate Change over the Past 1000 Years |year=2000 |last1=Crowley |first1=Thomas J. |journal=Science |volume=289 |issue=5477 |pages=270–277 |pmid=10894770 |bibcode=2000Sci...289..270C |url-access=subscription }}</ref>

In 1997, FCs and HFCs were included in the [[Kyoto Protocol]] to the Framework Convention on Climate Change.

In 2000 in the UK, the Ozone Regulations<ref>{{cite web|url=https://www.gov.uk/government/policies/protecting-and-enhancing-our-urban-and-natural-environment-to-improve-public-health-and-wellbeing/supporting-pages/controlling-ozone-depleting-substances-and-fluorinated-greenhouse-gases |title=2010 to 2015 government policy: environmental quality |website=GOV.UK |date=8 May 2015|access-date=10 June 2015}}</ref> came into force which banned the use of ozone-depleting HCFC refrigerants such as R22 in new systems. The Regulation banned the use of R22 as a "top-up" fluid for maintenance from 2010 for virgin fluid and from 2015 for recycled fluid.{{citation needed|date=March 2021}}