International Day for the Preservation of the Ozone Layer

International Day for the 

Preservation of the Ozone Layer

Ozone hole over Southern Hemisphere in 1957–2001

September 16 was designated by the United Nations General Assembly as the International Day for the Preservation of the Ozone Layer.

This designation was made on December 19, 1994, in commemoration of the date, in 1987, on which nations signed the Montreal Protocol on Substances that Deplete the Ozone Layer.