The world has agreed to begin phasing out hydrofluorocarbons HFCs , whose greenhouse effect is 10,000 as strong as carbon dioxide.
Nearly a year after the 197 signatories to the Montreal Protocol started work on an agreement covering HFCs, 170 countries have cut a binding accord to farewell the gases.
HFCs turn up in refrigerators, air conditioners, and are a popular alternative to halon in large-scale fire suppression systems such as are installed in data centres .
Its use as a replacement for chlorofluorocarbons CFCs ramped up after the Montreal Protocol came into effect in 1989, leading to the worldwide phase-out of the ozone-destroying gas.
Currently, HFC emissions are rising by 10 per cent annually.
The replacement chemicals, however, are a powerful greenhouse gas.