By the middle of the 1990s, the United States had banned the use of chlorofluorocarbon (CFC)-12, a refrigerant known for depleting ozone, in all new motor vehicle air conditioning (MVAC) systems. Hydrofluorocarbon (HFC)-134a has been the most used MVAC refrigerant since 1994. HFCs, or hydrofluorocarbons, are man-made fluorinated greenhouse gases utilized in the same ways as ozone-depleting compounds, such car air conditioners, have been employed. Most HFCs are powerful greenhouse gases with extremely significant global warming potentials, much like the ozone-depleting chemicals they are meant to replace (GWPs). In 2012, automakers started making the switch to more sustainable alternative refrigerants. Rulemaking in July 2015 mandated that HFC-134a be phased out of usage in MVAC systems for new light-duty cars in the United States by the 2021 model year.
Policy Initiative For Major New Options (SNAP)
Significant New Alternatives Policy (SNAP) is an EPA initiative that evaluates potential replacements for ozone-depleting compounds across a range of industries using a comparative risk methodology. The refrigeration and air conditioning industry includes MVAC systems as one application. Substitutes with lower ozone-depletion potential, global warming potential (GWP), flammability, toxicity, local air quality, ecological consequences, occupational safety, and consumer safety are identified and ranked by the SNAP program. Substitutes are categorized in SNAP as either acceptable, acceptable with restrictions on usage, or unacceptable. There is a list of MVAC refrigerants that are either allowed or unsuitable depending on the circumstances of usage.
The SNAP program also governs the retrofitting of CFC-12 MVAC units. All the changes in a vehicle are the ones that have been specifically cleared for use as retrofits by the Strategic National Stockpile Acquisition Program (SNAP). The most common replacement refrigerant for CFC-12 systems is HFC-134a. Check out the article on selecting and using retrofit refrigerants for a CFC-12 automobile air conditioner for more details.
For both new and existing MVAC installations, SNAP prohibits the use of any flammable refrigerants other than HFC-152a and HFO-1234yf. Everything that uses a hydrocarbon as a refrigerant falls under this category. If a refrigerant is banned, it cannot be used.
- Chlorofluorocarbon 12 is a refrigerant that depletes ozone
- Chemical used in air conditioning that has a global warming potential of 10,900
HFC-134a, a refrigerant that does not contribute to ozone depletion, was first used in 1992 model year automobiles. All new cars in the U.S. that have air conditioning utilized HFC-134a.
Ozone layer save living beings from the sun’s damaging ultraviolet (UV) rays because it lies in the stratosphere, between 30 and 50 miles above Earth’s surface. The degradation of the ozone layer in the upper atmosphere has harmful impacts on human health and the environment by allowing more ultraviolet radiation from the sun to reach the surface of the planet. Incidences of cataracts and skin cancer will rise, and immunity will be reduced. The same may be said for plastics, paints, and agricultural products as well as plant and animal life.
One must distinguish between ozone at terrestrial level and the stratospheric ozone layer. Ozone is beneficial at high altitudes but harmful at lower altitudes. While ozone up in the atmosphere acts as a shield, as it settles to Earth it becomes a major contributor to smog and is unhealthy to breathe.
- Greenhouse gas HFC-134a is quite powerful.
- Since the 1990s, this refrigerant has been the industry standard for MVAC units.
- It is estimated that 24 percent of all HFCs used worldwide are used in MVAC systems. In the atmosphere, it dominates all other HFCs.
Due to the EPA’s final rule under SNAP issued in July 2015, HFC-134a will no longer be allowed in new light-duty cars produced or sold in the United States beginning with the 2021 model year.
For automobiles intended for use in countries without facilities for servicing with alternative authorized refrigerants, the use of HFC-134a is exempt (within a tight usage restriction) until the end of the fiscal year 2025. r134a 30 lb can be used in servicing preexisting automobiles without any restrictions.
