An overview of how flammable refrigerants are changing the RAC landscape.

International and regional regulations, aimed at combating climate change, are resulting in a transition of the Refrigeration and Air-Conditioning (RAC) industry towards lower Global Warming Potential (GWP) refrigerant solutions. One of the consequences of these actions is that many of these alternatives (e.g. some hydrofluoroolefins [HFOs], hydrocarbons [HCs], etc.) are flammable. To this end, the RAC industry has spent the last several years preparing for this transition. This report will give an overview of some of the key factors that must be considered when working with flammable refrigerants. Regulatory drivers are discussed. Safety classes and flammability parameters are reviewed, as well as their effect on refrigerant selection. Finally, codes and standards impacts are also highlighted.