F-Gases

These gases comprise the following three families: HFCs (Hydroflurocarbons); PFCs (Perfluorcarbons); and SF₆ (Sulphur Hexafluoride).  While the ambient concentration of F-gases are much lower than those of the other greenhouse gases, the warming effect that they produce can be up to 23,900 times that of carbon dioxide.

Pollution: white furniture

Copyright John Doheny

Pollution: white furniture
Copyright John Doheny

Pollution: white furniture

Copyright John Doheny

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The impact of human activities

Halocarbon gas concentrations have increased primarily due to human activities. Traditional halocarbons include the chlorofluorocarbons (CFCs). These were used extensively as refrigeration agents and in other industrial processes before their presence in the atmosphere was found to cause stratospheric ozone depletion. The abundance of chlorofluorocarbon gases is decreasing as a result of international regulations designed to protect the ozone layer as agreed in the Montreal Protocol.

Some halocarbons that are effective in trapping heat are not restricted under the Montreal Protocol and have been employed as substitutes, i.e. the HFCs and PFCs. Due to their long atmospheric lifetimes they will continue trapping heat for centuries to come. HFC and PFC gases are used in refrigeration, air conditioning, the use of electrical equipment, fire extinguishers, and in the production of semiconductors.

SF₆ is used in four main markets: electrical insulation, magnesium smelting, electronics and training shoes.