With global stock of household air conditioners (ACs) expected to triple by 2050, continued use of HFCs in ACs is fueling the climate crisis. The International Electrotechnical Commission (IEC) is considering an updated safety standard IEC 60335-2-40, which covers household ACs, heat pumps and dehumidifiers. The proposed updated safety requirements will enable safe, energy efficient and cost-effective design of ACs using flammable low-global warming potential (GWP) refrigerants, including propane (R290). This briefing contains key information on the proposal, IEC process and timeline, and the climate benefits of enabling a timely transition to low-GWP refrigerants in the AC sector, which could avoid up to 5.6 billion tonnes of CO2 equivalent HFC consumption by 2050.