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 IX/24: Control of new substances with ozone-depleting potential

The Ninth Meeting of the Parties decided in Dec. IX/24:

  1. That any Party may bring to the attention of the Secretariat the existence of new substances which it believes have the potential to deplete the ozone layer and have the likelihood of substantial production, but which are not listed as controlled substances under Article 2 of the Protocol;
  2. To request the Secretariat to forward such information forthwith to the Scientific Assessment Panel and the Technology and Economic Assessment Panel;
  3. To request the Scientific Assessment Panel to carry out an assessment of the ozone-depleting potential of any such substances of which it is aware either as a result of information provided by Parties, or otherwise, to pass that information to the Technology and Economic Assessment Panel as soon as possible, and to report to the next ordinary Meeting of the Parties;
  4. To request the Technology and Economic Assessment Panel to report to each ordinary Meeting of the Parties on any such new substances of which it is aware either as a result of information provided by Parties, or otherwise, and for which the Scientific Assessment Panel has estimated to have a significant ozone-depleting potential. The report shall include an evaluation of the extent of use or potential use of each substance and if necessary the potential alternatives, and shall make recommendations on actions which the Parties should consider taking;
  5. To request Parties to discourage the development and promotion of new substances with a significant potential to deplete the ozone layer, technologies to use such substances and use of such substances in various applications.