The International Day for the Preservation of the Ozone Layer is a commemorative day established to raise awareness of the importance of protecting the stratospheric ozone layer and regulating ozone-depleting substances. Observed annually on September 16, the day marks the adoption of the Montreal Protocol — humanity's first successful international agreement for environmental protection — and was designated to remind the world of the importance of global cooperation and sustained effort in protecting the Earth's environment.
The stratospheric ozone layer, located 10 to 50 kilometers above the Earth's surface, acts as a natural shield by absorbing the sun's powerful ultraviolet radiation and protecting life on Earth. When this shield is damaged, the amount of ultraviolet radiation reaching the surface increases — causing a range of serious environmental problems, including various forms of skin cancer and cataracts, genetic mutations in terrestrial organisms, reduced agricultural yields, and the destruction of marine ecosystems.
From the 1970s onward, scientists began discovering that chemical substances such as chlorofluorocarbons (CFCs) were depleting the ozone layer. Starting with the 1985 Vienna Convention to regulate the use and production of such substances, the Montreal Protocol — regulating the production and use of ozone-depleting substances — was adopted in Montreal, Canada, on September 16, 1987. In 1994, the 49th UN General Assembly officially designated the International Day for the Preservation of the Ozone Layer, calling on all participating nations to mark the day with concrete actions aligned with the objectives of the Montreal Protocol.
[International Day for the Preservation of the Ozone Layer ⓒESG.ONL]
Each year, the United Nations Environment Programme (UNEP) uses this occasion to review the current state of ozone layer protection and announce new action guidelines. According to the Scientific Assessment of Ozone Depletion report published by UNEP in 2023, as a result of the Montreal Protocol, the ozone layer is currently recovering slowly — with the Antarctic ozone hole projected to fully recover by around 2066.
However, new challenges continue to emerge due to climate change and the appearance of new chemical substances, making the sustained attention and engagement of companies from an ESG management perspective increasingly important. In the semiconductor and chemical industries in particular, developing substitutes for ozone-depleting substances and adopting eco-friendly processes are becoming key indicators in ESG assessments.
The International Day for the Preservation of the Ozone Layer is more than a simple commemorative occasion — it is both a success story of human cooperation and action in the face of environmental crisis, and an important reminder of the need for sustained effort toward a sustainable future. When the small everyday practices that persist not just on September 16, but across all 365 days of the year, accumulate together, the sustainability of ozone layer protection and global environmental conservation will only grow stronger.
by Editor O