|MadSci Network: Engineering|
In a perfect world, there would be no refrigerant released into the atmosphere - it would be a closed system.
Unfortunately, we live in the real world, where nothing we build is perfect! CFC's can be released when a refrigerator is serviced, or the system may have tiny leaks that allow refrigerant to slowly leak out to the atmosphere. Neither of these conditions is unusual, it's just that the stuff that leaks out can be pretty dangerous in this case. Just think, the blood circulating in your body is pretty much in a closed system, but just a small scrape and all of a sudden you've sprung a leak. Since your blood doesn't deplete the ozone layer, nobody worries too much about regulating blood leaks!
Many countries around the world (including the US, where I live) have joined together to try to prevent these leaks from occurring. The Environmental Protection Agency here in the US has a website that provides more detailed information, including requirements on when leaky systems must be repaired and how existing CFC refrigerant must be recycled. This website also has a summary brochure that may answer a lot of more basic questions.
I hope this answers your question!
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