Perfluorocarbon. A flourinated greenhouse gas (see also HFC and SF6). PFCs are compounds produced as by-products of various industrial processes associated with aluminum production and the manufacturing of semiconductors in the electronics sector. PFCs are also used as refrigerants (mainly in blends with HFCs and HCFCs), as substitutes for ozon-depleting chemicals. Similarly to HFCs, PFCs generally have long atmospheric lifetimes and high global warming potential (see GWP). But since PFCs are released only in relatively small amounts, their contribution to global warming is small.