The Montreal Protocol on Substances that Deplete the Ozone Layer

The Montreal Protocol on Substances that Deplete the Ozone Layer is a global agreement to protect the Earth’s ozone layer by phasing out the chemicals that deplete it. This phase-out plan includes both the production and consumption of ozone-depleting substances. The landmark agreement was signed in 1987 and entered into force in 1989.

The parties to the Protocol meet once a year to make decisions aimed at ensuring the successful implementation of the agreement. These include adjusting or amending the Protocol, which has been done six times since its creation. The most recent amendment, the Kigali Amendment, called for the phase-down of hydrofluorocarbons (HFCs) in 2016. These HFCs were used as replacements for a batch of ozone-depleting substances eliminated by the original Montreal Protocol. Although they do not deplete the ozone layer, they are known to be powerful greenhouse gases and, thus, contributors to climate change.

The Montreal Protocol provided a set of practical, actionable tasks that were universally agreed on. The Protocol has successfully met its objectives thus far and continues to safeguard the ozone layer today. Thanks to the collaborative effort of nations around the world, the ozone layer is well on its way to recovery.

Decision XXXV/6: Updated information on very short-lived substances

Taking note with appreciation of the information on very short-lived substances in the 2022 quadrennial assessment report of the Scientific Assessment Panel and the 2022 assessment report of the Medical and Chemical Technical Options Committee of the Technology and Economic Assessment Panel,

To request the Technology and Economic Assessment Panel, in cooperation with the Scientific Assessment Panel, to include in its 2024 progress report, for consideration by the Open-ended Working Group of the Parties to the Montreal Protocol at its forty-sixth meeting:

  1. Updated information on very short-lived substances, including their ozone-depleting potential and the impact of each of the very short-lived substances on the stratospheric ozone layer, in quantifiable terms;
  2. Information on alternatives to very short-lived substances in the main applications for which they are currently used, including information on availability, technical feasibility, economic viability, safety and sustainability.