Figure 1. Examples of common refrigerants and their climate and environmental impacts
High-GWP: red; Medium-GWP: yellow; Low-GWP: green
| Type | GWP (20-yr) |
GWP (100-yr) |
Lifetime (yr) |
Ozone Depleting? |
PFAS? | Safety Class* |
|
|---|---|---|---|---|---|---|---|
| R11 | CFC | 8,320 | 6,230 | 52 | Yes | A1 | |
| R12 | CFC | 12,700 | 12,500 | 102 | Yes | A1 | |
| R22 | HCFC | 5,690 | 1,960 | 11.9 | Yes | A1 | |
| R141b | HCFC | 2,710 | 860 | 9.4 | Yes | ||
| R125 | HFC | 6,740 | 3,740 | 30 | No | Yes | A1 |
| R134a | HFC | 4,140 | 1,530 | 14 | No | Yes | A1 |
| R143a | HFC | 7,840 | 5,810 | 51 | No | Yes | A2L |
| R404A | HFC blend | 7,208 | 4,728 | No | Yes | A1 | |
| R407C | HFC blend | 4,457 | 1,908 | No | Yes | A1 | |
| R410A | HFC blend | 4,715 | 2,256 | No | Yes | A1 | |
| R452A | HFC/HFO blend | 4,273 | 2,292 | No | Yes | A1 | |
| R32 | HFC | 2,690 | 771 | 5.4 | No | No | A2L |
| R452B | HFC/HFO blend | 2,275 | 779 | No | Yes | A2L | |
| R454A | HFC/HFO blend | 943 | 270 | No | Yes | A2L | |
| R513A | HFC/HFO blend | 1,823 | 673 | No | Yes | A1 | |
| R290 (Propane) | Natural | 0.072 | 0.02 | 0.036 | No | No | A3 |
| R600a (Isobutane) | Natural | < 1 | < 1 | 0.019 | No | No | A3 |
| R717 (Ammonia) | Natural | < 1 | < 1 | < 1 | No | No | B2L |
| R744 (CO₂) | Natural | 1 | 1 | No | No | A1 | |
| R1234yf | HFO | 1.81 | 0.501 | 0.033 | No | Yes | A2L |
| R1234ze(E) | HFO | 4.94 | 1.37 | 0.052 | No | Yes | A2L |
*Safety classes based on ASHRAE Standard 34:
A1: non-flammable, lower toxicity
A2L: lower flammability, lower toxicity
A3: higher flammability, lower toxicity
B2L: lower flammability, higher toxicity
Sources:
Baha, M., & Dupont, J.-L. (2023, September 15). Global warming potential (GWP) of HFC refrigerants. International Institute of Refrigeration.
Behringer, D., Heydel, F., Gschrey, B., Osterheld, S., Schwarz, W., Warncke, K., Freeling, F., Nödler, K., Henne, S., Reimann, S., Blepp, M., Jörß, W., Liu, R., Ludig, S., Rüdenauer, I., & Gartiser, S. (2021). Persistent degradation products of halogenated refrigerants and blowing agents in the environment: Type, environmental concentrations, and fate with particular regard to new halogenated substitutes with low global warming potential. Final report. Umweltbundesamt [German Environment Agency].
Burkholder, J. B., Hodnebrog, Ø., McDonald, B. C., Orkin, V., Papadimitriou, V. C., & Van Hoomissen, D. (2023). Annex: Summary of abundances, lifetimes, ODPs, REs, GWPs, and GTPs. Scientific Assessment of Ozone Depletion 2022.
Garry, M. (2021, June 23). Certain HFCs and HFOs are in PFAS group that five EU countries intend to restrict.
Smith, C., Nicholls, Z. R. J., Armour, K., Collins, W., Forster, P., Meinshausen, M., Palmer, M. D., & Watanabe, M. (2021). The Earth’s energy budget, climate feedbacks, and climate sensitivity supplementary material. In Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change.
Trevisan, T. (2023, July 3). Overview of PFAS refrigerants used in HVAC&R and relevance of refrigerants in the PFAS Restriction Intention. UN Montreal Protocol 45th OEWG, Bangkok.
United Nations Environment Programme. (2023). Refrigeration, Air Conditioning and Heat Pumps Technical Options Committee: 2022 assessment report.
United Nations Environment Programme & ASHRAE. (2025). Update on new refrigerants designations and safety classifications June 2025.