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Ozone Generator designed
An ozone generator, now known as the "Siemens Type" ozone generator, is designed by a Werner Von Siemens. -
Discover chemial
Soret Jacques-Louis discovers the chemical formula for ozone. -
Doctors buying ozon generators
The Tesla Ozone Company is established and starts selling ozone generators to doctors -
Germany starts using ozone
Germany starts using ozone as a food preservative in the cold storage of meat -
Dobson spectrophotometer
the Dobson spectrophotometer is the earliest instrument used to measure ozone, and modern versions continue to provide data. -
Scientist Concern
Scientists began concerened about damage to this protective layer caused by atmospheric pollution -
CFCs
two United States chemists predicted that a class of chemicals called chlorofluorocarbons, widely used in aerosol spray cans, would seriously damage the ozone layer. -
Antarctic
British scientists produced the first direct evidence that this was actually happening. Antarctic atmospheric data going back to 1957 showed an alarming decline in ozone values over Antarctica each spring - effectively a hole in the ozone layer. -
Cause of the Ozone
an international team returned from the Antarctic to reveal that the cause of the ozone hole was human-produced chlorine and bromine molecules escaping to the stratosphere and, under ultraviolet radiation, breaking down into 'free' atoms which can break ozone molecules apart. The team found that in the very cold Antarctic stratosphere, ice crystals provide a surface on which ozone-destroying reactions can proceed apace. They found that in springtime, the combination of continuing cold condition -
US and Europe
CFC production ends in US and Europe
