Learn about EPA's efforts to address ozone layer depletion through international treaties and initiatives. The Montreal Protocol on Substances That Deplete the Ozone Layer is an international treaty designed to protect the ozone layerThe global recognition of the destructive potential of CFCs led to the 1987 Montreal Protocol, a treaty phasing out the production of ozone-depleting chemicals. For the purposes of this Protocol: 1. "Convention" means the Vienna Convention for the Protection of the. Learn about ozonedepleting substances, including what they are and how they contribute to ozone layer depletion and climate change. This document should be cited as: World Meteorological Organization (WMO). Scientific Assessment of Ozone Depletion: 2022, GAW Report No. 278,. As a result of the Montreal Protocol much more severe ozone depletion in the polar regions has been avoided. It provides for internationally coordinated control of ozone-depleting substances in order to protect a vital global resource.