A2L refrigerant compositions include hydrofluorolefins (HFO) such as R1234yf and R1234ze, hydrofluorocarbon(HFC) and hydrofluorolefin(HFO) blends such as R452B and R454B and some pure HFC’s such as R-32. These combinations result in a lower global warming potential (GWP) while maintaining the cooling efficiency required for commercial and residential applications. R410 A, currently used in air conditioners, is an A1 refrigerant that has no flame propagation at 63°C. Unlike the last refrigerant transition which shifted from the use of one nonflammable refrigerant to another, many of the new refrigerants are mildly flammable. HFO based A2L refrigerants are a cost-effective option and offer a GWP saving of up to 99.9% compared to HFCs while requiring only minimum equipment systems design change. In transitioning to more sustainable electric cooling the downside is additional training will be required of installers.