Question: Are HCFC’s (Hydrochlorofluorocarbons) currently allowed for air conditioning? Some of us thought that they were outlawed and this is why the thinning of the ozone layer (hole in the ozone) is reversing. [Louise & Kathy]
Response: There are 3 chemicals with very similar names and functions that might be confused.
Chlorofluorocarbons (CFCs) are nontoxic, nonflammable chemicals containing atoms of carbon, chlorine, and fluorine. They are used in the manufacture of aerosol sprays, blowing agents for foams and packing materials, as solvents, and as refrigerants.
Hydrofluorocarbons ‘HFCs‘ have been increasingly used in the last decade or so as an alternative to ozone damaging CFCs in refrigeration systems. Unfortunately, though they provide an effective alternative to CFCs, they can also be powerful greenhouse gases with long atmospheric lifetimes.
Hydrochlorofluorocarbons (HCFCs) are a large group of compounds, whose structure is very close to that of Chlorofluorocarbons (CFCs), but including one or more hydrogen atoms. Under normal conditions, HCFCs are gases or liquids which evaporate easily. They are generally fairly stable and unreactive, however, HCFCs are still greenhouse gases that may contribute to global warming.
Following from the EPA (https://www.epa.gov/mvac/refrigerant-transition-environmental-impacts)
“Following legislative regulations on ozone depleting (CFCs) and hydrochlorofluorocarbons (HCFCs), substances used as substitute refrigerants such as perfluorocarbons (FCs) and hydrofluorocarbons (HFCs) have also come under criticism. The provisions do not affect climate-neutral refrigerants.
Use of the ozone-depleting refrigerant, chlorofluorocarbon (CFC)-12, in new motor vehicle air conditioning (MVAC) systems ended in the mid-1990s in the United States. Since 1994, the most common refrigerant used in MVAC systems has been hydrofluorocarbon (HFC)-134a. HFCs are intentionally-made fluorinated greenhouse gases used in the same applications where ozone-depleting substances have been used, including motor vehicle air conditioning. Like the ozone-depleting substances they replace, most HFCs are potent greenhouse gases with very high global warming potentials (GWPs). In 2012, automobile manufacturers began the transition to new, climate-friendly alternative refrigerants. As a result of a July 2015 rulemaking, by model year 2021, the MVAC systems in newly manufactured light-duty vehicles in the United States will no longer use HFC-134a.”
However, there has been a transition to HCFC to replace CFC’s. What about HCFCs?
“HCFCs and the Ozone Layer
The stratospheric ozone layer shields the Earth from the sun’s harmful ultraviolet radiation. Emissions of certain synthetic chemicals—including CFCs, halons, and HCFCs—destroy the ozone layer, and have created an “ozone hole” over the South Pole.
Through the Montreal Protocol on Substances that Deplete the Ozone Layer, the United States committed to a collaborative, international effort to regulate and phase out ozone-depleting substances. While the US phased out of CFCs and halons in the mid 90’s, we now must reduce HCFC consumption in a step-wise fashion.
Phaseout of R-22 and R142b HCFC-22 (also called R-22) and HCFC-142b are the next two HCFCs that the United States will phase out.
The schedule to phase out HCFCs is:
- January 1, 2010 Ban on production, import and use of HCFC-22 and HCFC-142b, except for continuing servicing needs of existing equipment
- January 1, 2015 Ban on production, import, and use of all HCFCs, except for continuing servicing needs of refrigeration equipment
- January 1, 2020 Ban on remaining production and import of HCFC-22 and HCFC-142b. After 2020, the servicing of systems with R-22 will rely on recycled or stockpiled quantities January 1, 2030 Ban on remaining production and import of all HCFCs”
Additional information: https://learn.compactappliance.com/why-r22-freon-is-banned/