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Re: The "numbering system" section I was a chemist at the DuPont R&D facility in NJ where the Freons were manufactured. The mathematical system used was to represent the formula as #C, #H, and #F as a three digit number and then subtract 90. So, CCl3F would be represented as 101 which would equate to F-11 after subtracting 90.

(R-11, or CFC-11) (talk) 03:43, 2 November 2011 (UTC)

The system used in the article with the "plus 1" and "minus 1" results in the same designation, but it seems confusing and would certainly be harder to remember. Dcobranchi (talk) 13:53, 7 May 2010 (UTC)

CFC vs HCFC[edit]

The introduction states that CFCs contain C, F and Cl. For me it means that they do not contain hydrogen. In this case, however, HCFCs are not a subclass of CFCs (as it is stated in the second sentence), but they are an entirely separate class (without an intersection with CFCs). I do not know which statement is correct, but it should be clarified and the text corrected accordingly. Szaszicska (talk) 17:08, 1 August 2010 (UTC)

CFCs preceded HCFCs. HCFCs replaced CFCs. HFCs are and will replace HCFCs. it is all due to regulatory phase-outs of these chemicals due to their role in ozone depletion. (Their ODP or Ozone Depletion Potential) CFCs and HCFCs have an ODP or ozone depletion potential, due to their chlorine content, while HFCs contain no chlorine, and have no ODP, or an ODP of 0. — Preceding unsigned comment added by (talk) 03:40, 2 November 2011 (UTC)
This is an interesting claim as well. If an increase in HFCs has no effect (or zero potential) on ozone depletion, its reduction and its potential effects, then their growth shouldn't be expected to cause any offset in terms of the benefits of reducing ozone-depleting substances. Aside from all government regulations, HFCs are a known super-pollutant and do have a similar effect.

HFCs are super pollutants used in fridges, air conditioners and foam insulation. Thousands of times more potent than carbon dioxide, they could account for 19% of greenhouse gas emissions by 2050 if their manufacture continues unchecked.

— Megan Darby

Unfortunately, in many cases CFCs were replaced by HFCs, which do not damage the ozone layer but are similarly effective at heating up the planet. (talk) 15:25, 8 August 2014 (UTC)

──────────────────────────────────────────────────────────────────────────────────────────────────── Although Hydrochlorofluorocarbons and HCFC both redirect to the top of the article, one needs to scroll down until Chlorofluorocarbon § Classes of compounds, nomenclature in order to know that it stands for Hydro-chlorofluorocarbons. The lead sentence, however, implicitly excludes Hydro-chlorofluorocarbons from the article. I came to this article from Pentafluoropropane where it says: "Unlike CFC and HCFC...". Because both links point to "Chlorofluorocarbon" it is rather confusing. I think the lead should mention HCFC, as it appears in the article. At least the first instance of HCFC should mention "Hydro-chlorofluorocarbons" (not the case). It would also be helpful to know whether it should be written with a hyphen "Hydro-chlorofluorocarbons" (as in the article) or without a hyphen (as in the redirect Hydrochlorofluorocarbons. Rfassbind – talk 14:45, 17 July 2016 (UTC)

Carbon Dioxide as a coolant?[edit]

... One of the natural refrigerants (along with Ammonia and Carbon Dioxide),...
Can CO2 be used as a refrigerant?! If so how and where has it been done? What are the limitations?
Thanks, פשוט pashute ♫ (talk) 13:56, 24 January 2011 (UTC)
Found the answer. Co2#Refrigerant פשוט pashute ♫ (talk) 14:15, 24 January 2011 (UTC)
CO2 is a refrigerant that is in use. It's designation is R-744 (talk) 03:33, 2 November 2011 (UTC)— Preceding unsigned comment added by (talk) 03:26, 2 November 2011 (UTC)
A coolant is not a refrigerant, and a refrigerant is not a coolant (talk) 03:33, 2 November 2011 (UTC)

Ambiguous pronoun[edit]

The opening says " A chlorofluorocarbon (CFC) is an organic compound that contains carbon, chlorine, and fluorine, produced as a volatile derivative of methane and ethane. A common subclass is the hydrochlorofluorocarbons (HCFCs), which contain hydrogen, as well. They are also commonly known by the DuPont trade name Freon." Does the bold 'they' mean that CFC's are also known as Freon, or that HCFC's are? Smash bros master (talk) 01:46, 25 May 2011 (UTC)

Freon was once a trade name for R-12, or CFC-12. Now, it is used frequently, and incorectly to refer to many refrigerants. The term "freon" is used to refer to refrigerants in the CFC class, But the use of the term"freon" WOULD BE LESS SUITABLE to describe the newer HCFCs or HFCs, although it is often used to describe refrigerants in general, within the trade. this is an incorrect usage of the term FREON (talk) 03:54, 2 November 2011 (UTC) (talk) 03:29, 2 November 2011 (UTC)
"Freon" is a registered trademark of Dupont.

R-23 replacement? But it is global warming hazard too[edit]

The section with alternative replacements lists replacements for materials that are hazardous for the ozone layer. HFC 23 was listed as such a substitute for bad HCFC refrigerants. However, the article for HCFC 23 lists it as a substantial greenhouse gas contributor. The recommendation is not cited, so I presume the contributor listed it this way due to what I presume to be its negligible effect on the ozone layer. The section following this mentions the global warming hazard. Maybe what is needed in the alternatives section is emphasis on replacement from the POV of ozone dangers, not replacement in view of the totality of environmental risks. I have not researched it, so I don't know the answer. If you are reading this, the listing is still there and a reasonable amount of time has elapsed with no one defending this listing, I recommended modifying or clarifying the section or if an error was made, deleting the entry. J JMesserly (talk) 13:20, 11 May 2012 (UTC)

CFCs vs. HFCs[edit]

The article claims that CFCs are being replaced by HFCs, hydrocarbons, and CO2, because CFCs contribute to ozone depletion in the upper atmosphere. This claim implies that HFCs are being used as a solution to the problem of ozone depletion caused by CFCs. However, this is not necessarily the case. It should be noted that:

if HFC growth continues on the current trajectory, the increase in HFC emissions is projected to offset much of the climate benefit achieved by phasing out ozone-depleting substances.

— EPA (talk) 15:03, 8 August 2014 (UTC)

You say "However, this is not necessarily the case," but your following sentences do not contradict the idea that "HFCs are being used as a solution to the problem of ozone depletion caused by CFCs." Rather, they point out that substituting HFCs for CFCs does not solve the problem of radiative forcing and climate change caused by CFCs. As stated elsewhere on this talk page, maybe this distinction needs to be more clear in the article, but description of the relative effects of CFCs and HFCs on ozone depletion is not wrong.HeyRobbie (talk) 17:23, 28 January 2015 (UTC)