The Montreal Protocol on Substances that Deplete the Ozone Layer is an international treaty that was initiated as a result of the discovery of the Antarctic ozone hole in late 1985. It is designed to protect the ozone layer by phasing out the production of numerous substances believed to be responsible for ozone depletion.

 The treaty was opened for signature on September 16, 1987, and entered into force on January 1, 1989. Currently, more than 196 states have ratified the protocol.

The following substances are included in the Montreal Protocol

• Chlorofluorocarbons (CFCs)
• Halons
• Carbon tetrachloride
• Methyl chloroform
• Hydrochlorofluorocarbons (HCFCs)
• Hydrobromofluorocarbons (HBFCs)
• Methyl bromide

In order to provide assistance to developing countries, any Party whose annual calculated level of consumption of the controlled substances in Annex A (CFCs and Halons) is less than 0.3 kilograms per capita on the date of the entry into force of the Protocol, will hold Article 5 status. Article 5 parties are allowed to delay implementation of control provisions by ten years and may receive assistance under the Multilateral Fund. As of September 23, 2009, 147 countries hold Article 5 status including China, India and Brazil. A complete list of the Article 5 parties can be found here.

The U.S. is a member of the Montreal Protocol and has phased out the substances in accordance, as well has met all of the phase out schedules, and is on track to meet the upcoming ones.

Currently, there is a push to include HFCs in the Montreal Protocol. Some argue that HFCs are not o-zone depleting substances, and therefore, should be regulated under the Kyoto Protocol instead. Others argue that due to HFCs high Global Warming Potential (GWP), they should be included in the Montreal Protocol. There is a North American Proposal put forth by Canada, Mexico and the U.S. to phase down HFCs. It was proposed in 2009 and 2010, but has failed to gain enough support to fully move it forward. It is believed that it will be a major topic of continued discussions in 2011.

For AHRI’s position on the North American Proposal, please click here.

For more information, please visit http://ozone.unep.org.