February 1985, the British Antarctic Expedition Team Long Hair (J.Farman) reported for the first time that the total amount of ozone over Antarctica has been rapidly reduced by about half the year from 1977 to late October September, creating a "ozone hole" that continued to resume gradually November, causing a worldwide shock.
Ozone-depleting compounds, in addition to the snow species, are also used in aerosol propellants, foaming agents, and electronic components in the process of cleaning agent. Long life-containing bromine compounds, such as Al-haroun (Haion) Fire extinguishing agent, also play a significant role in ozone depletion.
Chlorine atoms and nitric oxide (NO) can react with ozone and are producing and using CFCs in the world as a result of refrigerants
Its chemical stability is good (such as the atmospheric life of CFC12 for 102 years) is not easy in the troposphere decomposition, through the atmospheric circulation into the ozone layer of the stratosphere, in the short wave ultraviolet UV-C irradiation, decomposition of the CI free radicals, involved in the consumption of ozone.
In order to make ozone depletion, this substance must have two characteristics: chlorine, bromine or another similar atom is involved in the chemical reactions of ozone oxygen, which must be very stable in the lower atmosphere (i.e., long enough atmospheric life) to reach the ozone layer. For example, HFCs HCF22 and HCFC123, all have a chlorine atom, can consume ozone, its atmospheric life is 12.1 and 14 respectively, and chlorine atoms relatively lively, can decompose in the lower atmosphere, the number of reaching the ozone layer is not much. Therefore, HCFC22 and HCFC123 destroy the ozone capacity is much smaller than CFCs.