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 XXII/11: Progress by the International Civil Aviation Organization in the transition from the use of halon

Recognizing with appreciation that the International Civil Aviation Organization General Assembly adopted resolution A37-9, on halon replacement, at its thirty-seventh session;

Acknowledging that resolution A37-9 states that there is an urgent need to continue developing and implementing halon alternatives for civil aviation; to intensify development of acceptable halon alternatives for fire-extinguishing systems in cargo compartments and engine/auxiliary power units; and to continue work to improve halon alternatives for hand-held fire extinguishers and directs the International Civil Aviation Organization Council to establish a mandate for the replacement of halon:

  1. In lavatory fire-extinguishing systems used in aircraft produced after a specified date in the 2011 time frame;
  2. In hand-held fire extinguishers used in aircraft produced after a specified date in the 2016 time frame;
  3. In engine and auxiliary power unit fire-extinguishing systems used in aircraft for which applications for type certification will be submitted after a specified date in the 2014 time frame,

Recalling that decision XXI/7 expresses the parties' continued support for the implementation of mandatory dates by which halon alternatives will be used in agreed applications for newly designed aircraft and requests that the Technology and Economic Assessment Panel and the Halons Technical Options Committee continue to engage the International Civil Aviation Organization on this issue and report on progress at the Twenty-Second Meeting of the Parties to the Montreal Protocol,

  1. To request the Secretariat to convey to the International Civil Aviation Organization secretariat the parties' appreciation for the continued work of its General Assembly and the adoption of resolution A37-9;
  2. To express the parties' continued support for the implementation of mandatory dates by which halon alternatives will be used in previously agreed-on applications in newly designed or newly produced aircraft consistent with resolution A37-9;
  3. To request that the Secretariat ask the International Civil Aviation Organization secretariat to send halon reserves data reported to the International Civil Aviation Organization to the Secretariat annually;
  4. To request that the Technology and Economic Assessment Panel and the Halons Technical Options Committee continue to engage with the International Civil Aviation Organization on further uses of halon on aircraft and report on progress at the Twenty-Third Meeting of the Parties;