<ul><li>The ozone layer, situated in the stratosphere about 15 to 30 km above the earth's surface, plays the important role of "space suit" that protects us living beings by absorbing harmful ultraviolet radiation (UVB) from the sun. </li></ul><ul><li>The ozone layer is currently being destroyed by CFCs and other substances, its depletion progressing globally except in the tropical zone. </li></ul>
<ul><li>The ozone layer is disappearing at a particularly high rate in high-latitude areas. In the Antarctic Circle, a large ozone hole has been observed for eight consecutive years from 1989 through 1996. </li></ul>Ozone Hole
Impact of ozone layer destruction <ul><li>Destruction of the ozone layer increases the amount of harmful ultraviolet radiation (UVB), which in turn can result in increased cases of skin cancer, and visual impediments such as cataract. </li></ul>
What is CFC? <ul><li>CFC, chlorofluorocarbon, is the collective name for compounds made of carbon, fluorine, chlorine and hydrogen. Because of their stable, harmless and non-combustible properties, they are widely used in everyday applications such as cleansing agents for electronic components, coolants for air conditioners, foaming agents for the manufacture of insulating materials and so on. CFC variations include HCFC and HFC. </li></ul>
<ul><li>CFC (Chlorofluorocarbon) Because of CFC's strong ozone layer-destroying effect, its production was totally banned at the end of 1995. It is necessary to ensure proper handling of CFC in appliances currently in use. </li></ul><ul><li>HCFC (Hydrochlorofluorocarbon) Although less powerful than CFC in destroying the ozone layer, HCFC must be also contained. </li></ul>
FINDING SOLUTIONS <ul><li>Despite the fact that, on the data known in the 1970s, the US Government banned the use of aerosols in 1978, it was not until 1987 that an international treaty, called the Montreal Convention, limiting the production of CFCs was signed by all the major industrial nations. The main users of CFCs agreed to reduce their consumption by 50% before the end of the century. However, experts said this reduction was insufficient and have suggested that a cut of 85% is needed if the ozone layer is to stand a chance of returning to normal within the next 50 years. That is how long it will take for harmful chemicals already in the atmosphere to work their way through. </li></ul>
PERSONAL RESPONSIBILITY <ul><li>While CFCs and other chemicals are being phased out we can all help reduce the damage to the ozone layer. </li></ul><ul><li>Buy only CFC-free aerosols </li></ul><ul><li>Carry out a survey of your home or the school's use of CFC products </li></ul><ul><li>If your family is buying a refrigerator choose one which is more ozone friendly and which can be serviced without any coolant gas being released into the air. Most manufacturers supply the information needed to make a wise choice. Also try to make sure that there are arrangements for the coolant gases to be removed from the old refrigerator before it is broken up. </li></ul>
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