Hydrofluorocarbons (HFCs) are primarily used as propellants in aerosols, foam agents, and fire retardants due to their ability to replace ozone-depleting substances. HFCs are generally not significant in lubricants, which typically rely on oils and other chemicals for their properties. Understanding the role of HFCs in these applications highlights the broader environmental considerations associated with refrigeration and aerosol products, as discussed in standard references like NCERT science textbooks and environmental science materials, which address the impacts of various chemicals on climate change and stratospheric ozone depletion.