HFC-125, or 1,1,1,2-tetrafluoroethane, is a colorless gas commonly used as a refrigerant in air conditioning systems and refrigeration equipment. It belongs to the hydrofluorocarbon (HFC) family, which are compounds designed to replace ozone-depleting substances like chlorofluorocarbons (CFCs). HFC-125 has a low toxicity and is non-flammable, making it a safer alternative for various applications. Despite its advantages, HFC-125 is a potent greenhouse gas with a high global warming potential (GWP). This has led to increased scrutiny and regulation under international agreements like the Montreal Protocol and the Paris Agreement. Efforts are underway to phase out HFCs in favor of more environmentally friendly alternatives.