The U.S. Environmental Protection Agency (EPA) has just announced a proposal that would ban the use of hydrofluorocarbons (HFCs) where climate-friendly alternatives are available instead. HFCs are a group of man-made chemicals containing the elements carbon, hydrogen and fluorine and were first used as refrigerants, mainly to help replace ozone destroying chlorofluorocarbons (CFCs). The problem is, now HFCs are found in so many products, including mobile air conditioners, food refrigeration systems, foam blowers, and aerosol propellants, which is very bad news for people and the environment. HFC’s are extremely potent greenhouse gases with global warming potentials hundreds to thousands of times higher than CO2 — and they are even sometimes called, “super greenhouse gases” because, as Think Global Green puts it, “the combined effect of their high use and high global warming potential could undercut the benefits expected from the reduction of other greenhouse gases such as carbon dioxide.” This ban will be the second major step in the EPA’s continued effort to reduce HFCs under President Obama’s Climate Action Plan (pdf) and complements an earlier action EPA proposed to expand the list of climate-friendly alternatives for refrigeration and air conditioning under its SNAP Program. According to the EPA, this ban will cut the equivalent of 42 million metric tons of carbon dioxide (CO2), which is clearly significant. The first bans would start in 2016 while mobile air conditioning HFC bans would start in 2020 for new 2021 model cars.