International Day for the Preservation of the Ozone Layer2026 · Date · History · Messages · Quotes
A/RES/49/114
About International Day for the Preservation of the Ozone Layer
International Day for the Preservation of the Ozone Layer is observed on 16 September. The day commemorates the 1987 signing of the Montreal Protocol on Substances that Deplete the Ozone Layer and highlights international cooperation to protect stratospheric ozone.
The ozone layer is a region of the stratosphere containing relatively high concentrations of ozone that absorb much of the Sun’s harmful ultraviolet radiation. Its protection is a distinct environmental issue from harmful ground-level ozone pollution.
Why International Day for the Preservation of the Ozone Layer matters
Ozone protection is a prominent example of science, international agreements, regulation, financing and technology working together over time. The Montreal Protocol controls production and consumption of specified ozone-depleting substances through agreed schedules and mechanisms.
The issue is sometimes confused with climate change. They are different problems, although some chemicals and policies—including the Kigali Amendment’s phase-down of hydrofluorocarbons—connect ozone governance with climate benefits.
History of International Day for the Preservation of the Ozone Layer
The Montreal Protocol was signed on 16 September 1987.
In 1994, the UN General Assembly proclaimed 16 September the International Day for the Preservation of the Ozone Layer through resolution 49/114.
How the observance developed
This timeline uses documented milestones from reviewed sources. Missing stages are left out rather than guessed.
United Nations General Assembly
UN General Assembly resolution 49/114
First documented observance
General Assembly resolution 49/114 explicitly states that the observance was to begin in 1995.
What the evidence establishes
Confirmed institutional roles and milestones are shown first. Details that could not be established from the reviewed sources are listed separately below.
4 fields not established in reviewed sources
How to Observe International Day for the Preservation of the Ozone Layer
Learn the difference between the protective ozone layer in the stratosphere and ground-level ozone, which is an air pollutant.
Use UN or national environmental-agency resources to understand how ozone-depleting substances are controlled where you live.
When replacing refrigeration or cooling equipment, use qualified providers and applicable rules for handling refrigerants rather than releasing them.
Explore how international environmental treaties are monitored and adjusted as scientific evidence and technology change.
Avoid presenting a single recovery date or climate benefit as permanent; scientific assessments and projections should be refreshed from current authoritative sources.
International Day for the Preservation of the Ozone Layer Facts
The observance is held on 16 September.
The date commemorates the signing of the Montreal Protocol in 1987.
The UN General Assembly proclaimed the international day in 1994 through resolution 49/114.
The stratospheric ozone layer protects life from harmful ultraviolet radiation.
Ground-level ozone is an air pollutant and should not be confused with the protective stratospheric ozone layer.
International Day for the Preservation of the Ozone Layer Messages
May International Day for the Preservation of the Ozone Layer inspire curiosity about the living world and thoughtful action to protect it.
Celebrate International Day for the Preservation of the Ozone Layer by learning from credible conservation sources and choosing one practical way to reduce harm or support protection.
Wishing everyone marking International Day for the Preservation of the Ozone Layer a day of discovery, respect for nature and care that continues beyond today.
On International Day for the Preservation of the Ozone Layer, may appreciation for the natural world lead to informed stewardship and practical care for the places and species around us.
International Day for the Preservation of the Ozone Layer Quotes
“As temperatures rise and extreme heat becomes more common, access to efficient cooling saves lives. We must meet that need fairly and sustainably.”
Topic and context
What this page does not assume
- Keep the source-defined country, community, organizer or institutional scope; do not silently broaden it.
- Do not treat the title alone as proof of government recognition or public-holiday status.
- Do not add a creator, founding story or origin claim unless the supporting evidence establishes it.
Evidence & sources
Sources used across the guide are gathered here. Labels show how each source supports the page, and contextual references are kept separate from primary evidence.
United Nations Digital Library — A/RES/49/114 (opens in a new tab)
United Nations — International Day for the Preservation of the Ozone Layer (opens in a new tab)
United Nations — List of International Days and Weeks (opens in a new tab)
United Nations — Observances: who chooses them and how (opens in a new tab)
Understand it, compare it, then explore further
Start with the most common factual questions, then compare closely related observances and explore useful connections.
Frequently asked questions
When is International Day for the Preservation of the Ozone Layer?
16 September The documented recurrence rule is: 16 September.
Does International Day for the Preservation of the Ozone Layer fall on the same date every year?
Yes. It uses a fixed annual date unless stronger evidence changes the pattern.
Is International Day for the Preservation of the Ozone Layer an official public holiday?
The reviewed sources verify it within this scope: United Nations / international observance. That recognition does not by itself make it a statutory public holiday; the site only makes public-holiday claims when reliable evidence explicitly does so.
Who established or recognizes International Day for the Preservation of the Ozone Layer?
The reviewed sources identify United Nations General Assembly as the proclaiming or establishing body.
Is International Day for the Preservation of the Ozone Layer international or country-specific?
The documented scope is international or global: United Nations / international observance. That does not mean every country treats the date as a public holiday or observes it in the same way.
How is this page verified?
The factual information is checked against reviewed sources, including the date pattern, scope and institutional history. This page was checked on 2026-09-05.
When is the International Day for the Preservation of the Ozone Layer?
It is observed every year on 16 September.
Why is it held on 16 September?
The date commemorates the signing of the Montreal Protocol on Substances that Deplete the Ozone Layer on 16 September 1987.
Is the ozone layer the same thing as ozone air pollution?
No. The protective ozone layer is in the stratosphere. Ground-level ozone is a harmful air pollutant formed near the Earth’s surface.
Other observances on September 16
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